CN111344850A

CN111344850A - Semiconductor chip with first protective film, method for manufacturing same, and method for evaluating semiconductor chip-first protective film laminate

Info

Publication number: CN111344850A
Application number: CN201880072997.8A
Authority: CN
Inventors: 佐藤明德; 四宫圭亮; 坂东沙也香
Original assignee: Lintec Corp
Current assignee: Lintec Corp
Priority date: 2017-11-17
Filing date: 2018-11-16
Publication date: 2020-06-26
Also published as: JPWO2019098326A1; TW201937573A; TWI794334B; KR20200083481A; JP7218296B2; WO2019098326A1; KR102594248B1

Abstract

The semiconductor chip with the first protective film according to the present embodiment includes a semiconductor chip and a first protective film formed on a surface of the semiconductor chip having a bump, and when the top of the bump is analyzed by X-ray photoelectron spectroscopy, a ratio of a concentration of tin to a total concentration of carbon, oxygen, silicon, and tin is 5% or more.

Description

Semiconductor chip with first protective film, method for manufacturing same, and method for evaluating semiconductor chip-first protective film laminate

Technical Field

The present invention relates to a semiconductor chip with a first protective film, a method for manufacturing the semiconductor chip with the first protective film, and a method for evaluating a semiconductor chip-first protective film laminate.

The present application is based on the priority claim of japanese patent application No. 2017-221987, filed in japan at 11/17/2017, the contents of which are incorporated herein by reference.

Background

Conventionally, when a multi-pin LSI package used for an MPU, a gate array, or the like is mounted on a printed wiring board, a flip-chip mounting method has been employed in which a semiconductor chip having protruding electrodes (hereinafter, referred to as "bumps" in this specification) made of eutectic solder, high-temperature solder, gold, or the like formed on connection pad portions thereof is used as a semiconductor chip, and these bumps are brought into contact with corresponding terminal portions on a chip mounting board by a so-called flip-chip method so as to be melt/diffusion bonded.

The semiconductor chip used in the mounting method can be obtained, for example, by: the surface of the semiconductor wafer having bumps formed on the circuit surface, which is opposite to the circuit surface (in other words, the bump formation surface), is ground or the semiconductor wafer is cut and singulated. In the process of obtaining the semiconductor chip, a curable resin film is generally attached to the bump formation surface for the purpose of protecting the bump formation surface of the semiconductor wafer and the bump, and the film is cured to form a protective film on the bump formation surface.

The curable resin film is generally attached to the bump formation surface of the semiconductor wafer in a state softened by heating. Thereby, the upper portion of the top portion of the head including the bump penetrates the curable resin film and protrudes from the curable resin film. On the other hand, the curable resin film spreads between the bumps so as to cover the bumps of the semiconductor wafer, adheres to the bump formation surface, and covers the surfaces of the bumps, particularly the surfaces of the portions in the vicinity of the bump formation surface, thereby embedding the bumps. Then, the curable resin film is further cured to cover the bump formation surface of the semiconductor wafer and the surface of the bump in the vicinity of the bump formation surface, and serves as a protective film for protecting these regions. Further, the semiconductor wafer is singulated into semiconductor chips, and finally, semiconductor chips provided with a protective film on the bump formation surface (in this specification, these semiconductor chips may be referred to as "semiconductor chips with a protective film").

The semiconductor chip with the protective film is mounted on a substrate to form a semiconductor package, and the semiconductor package is used to form a target semiconductor device. In order for the semiconductor package and the semiconductor device to function properly, it is necessary to prevent the bumps of the semiconductor chip with the protective film from being electrically connected to the circuits on the substrate. However, if the curable resin film is not properly attached to the bump formation surface of the semiconductor wafer, the bumps may not sufficiently protrude from the curable resin film, or a part of the curable resin film may remain on the top of the bumps. In this way, the curable resin film remaining on the top of the head of the bump is cured in the same manner as the curable resin film in the other region, and becomes a cured product having the same composition as the protective film (in this specification, this is sometimes referred to as "protective film residue"). In this way, since the top of the bump is an electrical connection region between the bump and the circuit on the substrate, when the amount of the residue of the protective film is large, the electrical connection between the bump of the semiconductor chip with the protective film and the circuit on the substrate is hindered. As a result, the reliability of the semiconductor package is reduced, and the semiconductor device cannot function normally.

That is, at a stage before the semiconductor chip with the protective film is mounted on the substrate, it is required that no protective film residue is present on the tops of the bumps of the semiconductor chip with the protective film or the amount of the protective film residue is small.

As a method capable of suppressing the residue of the protective film from remaining on the top of the head of the bump, there is disclosed a method using a curable resin film (adhesive layer) containing a high molecular weight component having a weight average molecular weight of 2 to 100 ten thousand, a thermosetting resin, a curing accelerator, a photoreactive monomer, and a photoinitiator (see patent document 1).

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 5515811

Disclosure of Invention

Technical problem to be solved by the invention

In general, when many minute irregularities exist on the surface of the bump and a protective film residue exists on the top of the head of the bump, the protective film residue may intrude into the recess of the bump surface. Therefore, it is difficult to evaluate the amount of the protective film residue on the top of the heads of the bumps.

In contrast, in the method described in patent document 1, the presence or absence of a residue from the curable resin film (adhesive layer) on the top of the head of the bump is evaluated by observation with the naked eye or with a microscope. As described above, this method has a problem that it is not possible to evaluate the amount of the resist residue on the top of the head of the bump with higher accuracy, such as quantifying the amount of the resist residue on the top of the head of the bump, and it is not clear whether or not the residue on the top of the head of the bump is actually suppressed. Further, the reliability of the semiconductor package is not evaluated using the semiconductor chip with a protective film obtained by this method, and there is a problem that it is not clear whether or not the semiconductor package has sufficient reliability.

The invention aims to provide a semiconductor chip with a protective film, a manufacturing method of the semiconductor chip with the protective film and an evaluation method capable of evaluating whether the semiconductor chip with the protective film is the semiconductor chip with the protective film with high precision, wherein the semiconductor chip with the protective film is formed by inhibiting residues of the protective film from remaining on the tops of bumps.

Means for solving the problems

The present invention provides a semiconductor chip with a first protective film, which comprises a semiconductor chip and the first protective film formed on the surface of the semiconductor chip having a bump, wherein when the top of the bump is analyzed by X-ray photoelectron spectroscopy, the ratio of the concentration of tin to the total concentration of carbon, oxygen, silicon and tin is 5% or more.

Further, the present invention provides a method for manufacturing a semiconductor chip with a first protective film, including: a step of attaching a curable resin film to the surface of the semiconductor wafer having the bumps; forming a first protective film by curing the cured resin film after the application; and a step of obtaining a semiconductor chip by dividing the semiconductor wafer, wherein in the step of attaching the curable resin film, the top portion of the bump is caused to protrude from the curable resin film so that the ratio of the tin concentration is 5% or more, or the step of attaching the curable resin film is further provided with a step of reducing the amount of residue on the bump so that the ratio of the tin concentration is 5% or more.

Further, the present invention provides a method for evaluating a semiconductor chip-first protective film laminate, the evaluation method of a semiconductor chip-first protective film laminate comprising a semiconductor chip and a first protective film formed on a surface of the semiconductor chip having a bump, wherein the top of the bump in the semiconductor chip-first protective film laminate is analyzed by X-ray photoelectron spectroscopy to determine the ratio of the concentration of tin to the total concentration of carbon, oxygen, silicon and tin, determining the semiconductor chip-first protective film laminate as a target semiconductor chip with a first protective film when the ratio of the tin concentration is 5% or more, when the ratio of the concentration of tin is less than 5%, the semiconductor chip-first protective film laminate is determined as a semiconductor chip with a first protective film that is not an object.

Effects of the invention

By using the semiconductor chip with the first protective film of the present invention, a semiconductor package having sufficient reliability can be configured.

By applying the method for manufacturing a semiconductor chip with a first protective film according to the present invention, the semiconductor chip with the first protective film can be manufactured.

By applying the method for evaluating a semiconductor chip-first protective film laminate of the present invention, it is possible to evaluate with high accuracy whether or not the semiconductor chip-first protective film laminate is the above-described semiconductor chip with the first protective film.

Drawings

Fig. 1 is an enlarged cross-sectional view schematically showing one embodiment of a semiconductor chip with a first protective film according to the present invention.

Fig. 2 is an enlarged cross-sectional view schematically showing another embodiment of the semiconductor chip with the first protective film according to the present invention.

Fig. 3 is an enlarged cross-sectional view schematically showing another embodiment of the semiconductor chip with the first protective film according to the present invention.

Fig. 4 is an enlarged cross-sectional view schematically showing another embodiment of the semiconductor chip with the first protective film according to the present invention.

Fig. 5 is an enlarged sectional view schematically illustrating an embodiment of a method for manufacturing a semiconductor chip with a first protective film according to the present invention.

Fig. 6 is an enlarged cross-sectional view schematically showing an example of a first protective film forming sheet in which the method for manufacturing a semiconductor chip with a first protective film according to the present invention is used.

Fig. 7 is an enlarged cross-sectional view schematically illustrating an example of a step of reducing the amount of residue on the bump in the method for manufacturing a semiconductor chip with a first protective film according to the present invention.

Fig. 8 is an enlarged cross-sectional view schematically illustrating another example of the step of reducing the amount of residue on the bump in the method for manufacturing a semiconductor chip with a first protective film according to the present invention.

Fig. 9 is an enlarged cross-sectional view schematically illustrating another example of the step of reducing the amount of residue on the bump in the method for manufacturing a semiconductor chip with a first protective film according to the present invention.

Fig. 10 is an enlarged cross-sectional view schematically illustrating another example of the step of reducing the amount of residue on the bump in the method for manufacturing a semiconductor chip with a first protective film according to the present invention.

Fig. 11 is a plan view for explaining a position where the semiconductor chip-first protective film laminate as an object of XPS analysis of the top of head of the bump is arranged on the dicing tape (dicing tape) in the embodiment.

Detailed Description

◇ semiconductor chip with first protective film

The semiconductor chip with the first protective film of the present invention includes a semiconductor chip and a first protective film formed on a surface of the semiconductor chip having a bump (in this specification, this may be referred to as a "bump formation surface"), and when the top of the bump is analyzed by X-ray Photoelectron Spectroscopy (in this specification, this may be referred to as "XPS"), the ratio of the concentration of tin to the total concentration of carbon, oxygen, silicon, and tin (in this specification, this may be referred to simply as a "ratio of the concentration of tin") is 5% or more.

When the top of the head of the bump is analyzed by XPS, a signal of tin (Sn) may be generally detected. This is because the bump contains tin as its constituent material.

On the other hand, the bump does not contain an organic compound as its constituent material. Therefore, the signal of carbon (C) detected when the top of the head of the bump is analyzed by XPS is due to the presence of an organic compound that should not be present in the analysis region (i.e., the top of the head of the bump). The organic compound is derived from a curable resin film used in forming the first protective film. When the curable resin film is attached to the bump formation surface, if an originally unnecessary curable resin film remains on the top of the head of the bump, the residue (in this specification, it may be referred to as "curable resin film residue") is cured to become a cured product having the same composition as the first protective film (in this specification, it may be referred to as "first protective film residue"). The first protective film residue contains the organic compound described above. If the first protective film residue is present, a signal of carbon (C) is detected when the top of the head of the bump is analyzed by XPS. In addition, when the top of the head of the bump is analyzed by XPS, signals of oxygen (O) and silicon (Si) may be detected in addition to carbon (C). This is because a film containing a non-resin component such as silica is widely used as the first protective film. The method for manufacturing a semiconductor chip with a first protective film according to the present invention will be described in detail below.

In the semiconductor chip with the first protective film, a ratio of the concentration of the tin at the top of the head of the bump is 5% or more. This indicates that the total amount of carbon, oxygen, and silicon is below a certain level with respect to the amount of tin at the top of the head of the bump. That is, the semiconductor chip with the first protection film does not have the first protection film residue on the crown portion of the bump, or the amount of the first protection film residue is small, the residue of the first protection film residue is suppressed. In this way, by suppressing the first protective film residue from remaining on the crown portion of the bump, the bonding strength between the bump and the substrate becomes high when the semiconductor chip with the first protective film is used. Further, the junction of the semiconductor chip and the substrate has high electrical connectivity and excellent conductivity. Further, by using the semiconductor chip with the first protective film, a semiconductor package having sufficient reliability can be formed, and a semiconductor device having excellent characteristics can be formed.

In addition, in the present specification, unless otherwise specified, "the amount of the first protection film residue on the overhead portion of the bump is small" means: although a small amount of the first protective film residue remains on the top of the head of the bump, the remaining amount is such an amount that does not hinder the electrical connection between the semiconductor chip and the wiring board when the semiconductor chip flip-chip having the bump is mounted on the wiring board.

The surface of the semiconductor wafer opposite to the bump formation surface may be referred to as a "back surface".

The surface of the bump in the semiconductor chip with the first protection film has many minute irregularities, and when the first protection film residue exists on the crown portion of the bump, the first protection film residue may intrude into the recess of the bump surface. The first protective film residue in the recess is difficult to visually confirm and quantify, and this tendency is strong particularly when the amount of the first protective film residue is small. In contrast, in the semiconductor chip with the first protection film of the present invention, the degree of the first protection film residue on the overhead portion of the bump can be precisely determined according to the analysis result using XPS. Therefore, the semiconductor chip with the first protection film of the present invention is extremely high in reliability in terms of the amount of the first protection film residue.

In the semiconductor chip with the first protection film, the ratio of the tin concentration at the top of the bump ([ tin concentration (%) ]/[ total concentration of carbon, oxygen, silicon, and tin (atomic%) ] × 100) is 5% or more, preferably 5.4% or more, more preferably 5.8% or more, further preferably 6.2% or more, and may be any one of ranges of 7.5% or more, 9% or more, 10.5% or more, and 12% or more, for example.

In the semiconductor chip with the first protective film, the upper limit value of the ratio of the tin concentration at the top of the head of the bump is not particularly limited as long as it is 100% or less. For example, the ratio of the concentration of tin may be in any range of 25% or less and 20% or less, and the semiconductor chip with the first protective film can be manufactured more easily.

The ratio of the tin concentration at the top of the head of the bump can be appropriately adjusted within a range set by arbitrarily combining any of the lower limit value and the upper limit value described above.

For example, in one embodiment, the concentration ratio of tin is preferably 5 to 25%, more preferably 5.4 to 25%, further preferably 5.8 to 25%, particularly preferably 6.2 to 25%, and may be, for example, any one of 7.5 to 25%, 9 to 25%, 10.5 to 25%, 12 to 25%, and the like. In one embodiment, the concentration ratio of tin is preferably 5 to 20%, more preferably 5.4 to 20%, further preferably 5.8 to 20%, particularly preferably 6.2 to 20%, and may be, for example, any one of 7.5 to 20%, 9 to 20%, 10.5 to 20%, 12 to 20%, and the like. However, these values are only one example of the ratio of the tin concentration.

The top of the head of the bump subjected to XPS analysis refers to an upper region including the top of the bump. Examples of the crown include: the bump is preferably a region including a top of the bump and recognized as a circular region having a diameter of 10 to 30 μm, more preferably a region recognized as a circular region having a diameter of 15 to 25 μm, for example, a region recognized as a circular region having a diameter of 20 μm or the like, when viewed from above and downward. By setting the diameter to be equal to or greater than the lower limit value, XPS analysis can be performed with higher accuracy. By setting the diameter to the upper limit value or less, XPS analysis can be performed with higher efficiency.

When the surface of the upper region of the bump is a curved surface, a position having the highest height from the bump forming surface of the semiconductor chip may be selected as the apex of the bump. On the other hand, when the surface of the upper region of the bump is a plane, for example, the center (center of gravity) of the plane may be selected as the apex of the bump.

The shape of the bump will be described in detail later.

The analysis conditions when XPS is used are not particularly limited. However, the irradiation angle of the X-ray is preferably 15 to 90 DEG, the beam diameter of the X-ray is preferably 9 to 100 [ mu ] m, and the output when the X-ray is irradiated is preferably 1 to 100W. By setting the above conditions, analysis can be performed with higher accuracy.

The beam diameter of the X-ray can be set to the same size as the top of the head of the bump subjected to XPS analysis.

Fig. 1 is an enlarged cross-sectional view schematically showing one embodiment of a semiconductor chip with a first protective film according to the present invention. In addition, in the drawings used in the following description, for the sake of easy understanding of the features of the present invention, the main portion may be enlarged for convenience, and the dimensional ratios of the respective components are not necessarily the same as those in the actual case.

The semiconductor chip 1 with the first protection film shown here includes a semiconductor chip 9, and a first protection film 13 formed on a surface (bump forming surface) 9a of the semiconductor chip 9 having a bump.

In the semiconductor chip 1 with the first protective film, the first protective film 13 covers the surface 91a of the bump 91, particularly the surface 91a in the vicinity of the bump forming surface 9a, while adhering to the bump forming surface 9a, thereby embedding the bump 91 and protecting these regions.

In fig. 1, reference numeral 9b denotes a surface (back surface) of the semiconductor chip 9 opposite to the bump formation surface 9 a.

The top 910 of the bump 91 penetrates the first protection film 13 and protrudes. Further, there is no first protective film residue at the top 910 of the bump 91. Therefore, when the head top portion 910 of the bump 91 is subjected to XPS analysis, the ratio of the concentration of tin is high at 5% or more.

The bump 91 has a shape in which a part of a ball is cut out in a plane, and the plane corresponding to the cut-out and exposed portion is in a state of being in contact with a bump formation surface (circuit surface) 9a of the semiconductor chip 9.

The shape of the bump 91 can be said to be substantially spherical.

The top 910 of the projection 91 can be said to be a part of a sphere, which is curved.

The height of the bump 91 is not particularly limited, but is preferably 60 to 450 μm, more preferably 120 to 300 μm, and particularly preferably 180 to 240 μm. By setting the height of the bump 91 to be equal to or higher than the lower limit value, the function of the bump 91 can be further improved. Further, by making the height of the bump 91 the upper limit value or less, the effect of suppressing the first protective film residue from remaining on the crown portion 910 of the bump 91 becomes higher.

In the present specification, the "height of the bump" refers to the height of a portion (apex) of the bump located at the highest position from the bump forming surface.

The width of the bump 91 is not particularly limited, but is preferably 170 to 350 μm, more preferably 200 to 320 μm, and particularly preferably 230 to 290 μm. By setting the width of the bump 91 to be equal to or greater than the lower limit value, the function of the bump 91 can be further improved. Further, by making the width of the bump 91 the upper limit value or less, the effect of suppressing the first protective film residue from remaining on the crown portion 910 of the bump 91 becomes higher.

In the present specification, the "width of the bump" refers to the maximum value of a line segment connecting two different points on the surface of the bump with a straight line when the bump is viewed from the direction perpendicular to the bump formation surface in a downward direction.

The distance between the adjacent bumps 91 is not particularly limited, but is preferably 80 to 1000 μm, more preferably 100 to 800 μm, and particularly preferably 120 to 550 μm. By setting the distance to be equal to or greater than the lower limit value, the function of the bump 91 can be further improved. Further, by making the distance the upper limit value or less, the effect of suppressing the first protective film residue from remaining on the crown portion 910 of the bump 91 becomes higher.

In the present specification, the "distance between adjacent bumps" refers to a pitch of central portions between adjacent bumps, and may be referred to as a "bump pitch".

Here, as the semiconductor chip with the first protection film, although the chip without the first protection film residue on the crown of the bump is shown, the semiconductor chip with the first protection film of the present invention may have a small amount of the first protection film residue on the crown of the bump. The amount of the first protective film residue in this case may be small as described above.

Fig. 2 is an enlarged cross-sectional view schematically showing an embodiment of the semiconductor chip with the first protective film according to the present invention. In the drawings subsequent to fig. 2, the same components as those shown in the already-described drawings are denoted by the same reference numerals as those in the already-described drawings, and detailed description thereof will be omitted.

The semiconductor chip 2 with the first protection film shown here is the same as the semiconductor chip 1 with the first protection film shown in fig. 1 except that a small amount of the first protection film residue 131 exists on the crown portion 910 of the bump 91.

Although the semiconductor chip 2 with the first protection film has the first protection film residue 131 remaining therein, the top 910 of the bump 91 still penetrates the first protection film 13 and protrudes.

The amount of the first protective film residue 131 of the semiconductor chip 2 with the first protective film on the crown portion 910 of the bump 91 is small, suppressing the residue of the first protective film residue 131. Therefore, when the head top portion 910 of the bump 91 is subjected to XPS analysis, the ratio of the concentration of tin is high at 5% or more.

The semiconductor chip 2 with the first protection film is shown in a case where the first protection film residue 131 exists so as to extend to a narrow region of the surface 91a of the bump 91 with the apex of the crown portion 910 of the bump 91 being substantially centered. However, when the first protective film residue 131 exists, the existing region thereof is not limited thereto, and for example, the apex of the bump 91 or the vicinity thereof may not be centered. In the present specification, the "apex of the bump (apex of the top of the head of the bump)" means a position on the surface of the bump having the highest height from the bump forming surface of the semiconductor chip.

Although the semiconductor chip with the first protection film has been described as a chip with a bump having a substantially spherical shape, the shape of the bump is not limited to this in the semiconductor chip with the first protection film of the present invention.

Fig. 3 is an enlarged cross-sectional view schematically showing an embodiment of the present invention in a case where the shape of the bump in the semiconductor chip with the first protection film is not substantially spherical.

The semiconductor chip 3 with the first protection film shown here is the same as the semiconductor chip 1 with the first protection film shown in fig. 1, except that the bump 92 is provided instead of the bump 91 (i.e., the bump has a different shape).

More specifically, regarding the bump 92, the vertex 910 in the bump 91 shown in fig. 1 is not a curved surface but a flat surface. That is, the top 920 of the head of the bump 92 is a flat surface.

In fig. 3, reference numeral 92a denotes the surface of the region of the bump 92 other than the parietal region 920.

The face of the top 920 of the bump 92 may or may not be parallel to the bump formation face 9a of the semiconductor chip 9, for example. When not parallel, the orientation of the face of the crown 920 is not particularly limited.

The crown 920 of the bump 92 penetrates the first protection film 13 and protrudes. Further, there is no first protective film residue on the crown 920 of the bump 92. Therefore, when the head top portion 920 of the bump 92 is subjected to XPS analysis, the ratio of the concentration of tin is high, i.e., 5% or more.

The width of the bump 92 and the distance between adjacent bumps 92 are the same as in the case of the bump 91 shown in fig. 1.

The height of the bump 92 is not particularly limited, but is preferably 40 to 390 μm, more preferably 70 to 250 μm, and particularly preferably 130 to 190 μm. If the height of the bump 92 is equal to or greater than the lower limit, the function of the bump 92 can be further improved. Further, by making the height of the bump 92 the upper limit value or less, the effect of suppressing the first protective film residue from remaining on the crown 920 of the bump 92 becomes higher.

Fig. 4 is an enlarged sectional view schematically showing an embodiment of the present invention when a small amount of first protective film residue is present on the crown portion of the bump in the semiconductor chip with the first protective film.

The semiconductor chip with the first protection film 4 shown here is the same as the semiconductor chip with the first protection film 3 shown in fig. 3, except that a small amount of the first protection film residue 131 exists on the crown portion 920 of the bump 92.

Although the semiconductor chip 4 with the first protection film has the first protection film residue 131 remaining therein, the crown 920 of the bump 92 does not protrude through the first protection film 13.

The amount of the first protective film residue 131 of the semiconductor chip 4 with the first protective film on the crown 920 of the bump 92 is small, suppressing the residue of the first protective film residue 131. Therefore, when the head top portion 920 of the bump 92 is subjected to XPS analysis, the ratio of the concentration of tin is high, i.e., 5% or more.

The semiconductor chip 4 with the first protection film is shown in a case where the first protection film residue 131 is present extending from substantially the center in the crown 920 of the bump 92 to a narrow region in the periphery. However, when the first protective film residue 131 is present, the present region is not limited to this, and may be present without extending from the substantially center of the bump 92 to the surrounding region, for example.

The semiconductor chip with the first protective film according to the present invention is not limited to the chip shown in fig. 1 to 4, and for example, a part of the structure of the chip shown in fig. 1 to 4 may be modified, deleted, or added within a range not to impair the effect of the present invention.

For example, the semiconductor chip with the first protective film shown in fig. 1 to 4 does not include any member on the back surface 9b of the semiconductor chip 9, and the back surface 9b is an exposed surface, but the semiconductor chip with the first protective film according to the present invention may include an arbitrary layer (film) such as a protective film (which may be referred to as a "second protective film" in this specification) on the back surface of the semiconductor wafer.

In order to produce the semiconductor chip, the second protective film prevents the semiconductor chip from cracking when the semiconductor wafer is diced or until the semiconductor chip obtained by dicing is packaged to manufacture a semiconductor device.

The second protective film is typically a resin film.

Next, a semiconductor chip and a first protective film constituting the semiconductor chip with the first protective film will be described.

Semiconductor chip

The semiconductor chip is not particularly limited as long as it has bumps on a bump formation surface (also referred to as a surface provided with a circuit or a circuit surface) and can be used for flip-chip mounting.

In the semiconductor chip, tin (Sn) is exemplified as a metal contained in the bump as a constituent material thereof, and further, metals other than tin are exemplified by gold (Au), silver (Ag), copper (Cu), and the like.

The bump may be composed of only one kind of material, or may be composed of two or more kinds of materials, and when the number of materials is two or more, the combination and ratio thereof may be arbitrarily selected.

The shape, size, and arrangement of the bumps are as described above.

In the semiconductor chip, the material and size of the portion from which the bump is removed may be the same as those of known materials and sizes.

For example, the thickness of the semiconductor chip at the portion where the bump is removed is preferably 50 to 780 μm, and more preferably 150 to 400 μm.

First protective film

In the semiconductor chip with the first protective film, the first protective film is in close contact with the bump forming surface of the semiconductor chip and covers the surface of the bump, particularly the surface of the semiconductor chip in the vicinity of the bump forming surface, thereby embedding the bump. In this way, the first protective film covers the surface of the semiconductor chip at the bump forming surface and the vicinity of the bump forming surface of the bump, thereby protecting these regions. Further, a partial void may exist between the surface of the bump in the vicinity of the bump forming surface and the first protection film.

The first protective film is generally a resin film containing a resin component, and may be formed using a curable resin film for forming the first protective film by curing. The curable resin film can be formed using a curable resin film-forming composition containing the constituent material. For example, a curable resin film can be formed on a target site by applying the curable resin film-forming composition to a surface to be formed of a curable resin film and drying the composition as necessary. The ratio of the content of the components that do not vaporize at normal temperature in the composition for forming a curable resin film is generally the same as the ratio of the content of the components of the curable resin film, and in the present specification, "normal temperature" means a temperature at which cooling or heating is not particularly performed, that is, a normal temperature, and examples thereof include a temperature of 15 to 25 ℃.

The components corresponding to the resin in the thermosetting resin film-forming composition and the energy ray-curable resin film-forming composition described later are contained in the resin component.

In this manner, the first protective film can be formed by forming a curable resin film using the composition for forming a curable resin film and then curing the curable resin film.

The curable resin film-forming composition may be applied by a known method. Examples of the coating method include a method using various coaters such as an air knife coater, a blade coater, a bar coater, a gravure coater, a roll coater, a curtain coater, a die coater, a knife coater, a screen coater, a meyer bar coater, and a kiss coater.

The drying conditions of the curable resin film-forming composition are not particularly limited, and it is preferable to appropriately adjust the drying conditions so that the curable components in the composition do not undergo curing other than the intended curing.

For example, when the curable resin film-forming composition contains a solvent described later, it is preferably dried by heating. The solvent-containing composition for forming a curable resin film is preferably dried at 70 to 130 ℃ for 10 seconds to 5 minutes, for example.

The first protective film may be a single layer (single layer) or a plurality of layers of two or more layers, and in the case of a plurality of layers, these plurality of layers may be the same or different from each other, and the combination of these plurality of layers is not particularly limited.

In the present specification, the phrase "a plurality of layers may be the same or different from each other" means "all the layers may be the same or all the layers may be different from each other, or only a part of the layers may be the same" and "the plurality of layers are different from each other" means "at least one of the constituent material and the thickness of each layer is different from each other".

The thickness of the first protective film is preferably 1 to 100 μm, more preferably 5 to 75 μm, and particularly preferably 5 to 50 μm. By making the thickness of the first protection film be equal to or greater than the lower limit value, the protection performance of the first protection film becomes higher. By making the thickness of the first protection film the upper limit value or less, the effect of suppressing the first protection film residue from remaining on the crown portion of the bump becomes higher.

Here, the "thickness of the first protection film" refers to the thickness of the entire first protection film, and for example, the thickness of the first protection film formed of a plurality of layers refers to the total thickness of all layers constituting the first protection film.

The first protective film may be any one of a cured product of a thermosetting resin film and a cured product of an energy ray-curable resin film. That is, the first protective film can be formed using either a composition for forming a thermosetting resin film or a composition for forming an energy ray-curable resin film.

In the present specification, the term "energy ray" refers to a ray having an energy quantum in an electromagnetic wave or a charged particle beam, and examples thereof include ultraviolet rays, radiation, electron beams, and the like.

The ultraviolet rays can be irradiated by using, for example, a high-pressure mercury lamp, a fusion H lamp, a xenon lamp, a black light lamp, an LED lamp, or the like as an ultraviolet light source. The electron beam may be irradiated with an electron beam generated by an electron beam accelerator or the like.

In the present invention, "energy ray-curable property" refers to a property of curing by irradiation with an energy ray, and "non-energy ray-curable property" refers to a property of not curing even by irradiation with an energy ray.

◎ thermosetting resin film-forming composition

○ composition for Forming resin layer (III)

Examples of the composition for forming a thermosetting resin film include a composition (III) for forming a thermosetting resin film containing a polymer component (a) and a thermosetting component (B) (in the present specification, this may be abbreviated as "composition (III) for forming a resin layer").

[ Polymer component (A) ]

The polymer component (a) is a polymer compound for imparting film formability, flexibility, or the like to a thermosetting resin film, and the polymerizable compound is considered to be a component formed by performing a polymerization reaction. In addition, the polymerization reaction in the present specification also includes a polycondensation reaction.

The polymer component (a) contained in the resin layer forming composition (III) and the thermosetting resin film may be one type or two or more types, and when two or more types are contained, the combination and ratio thereof may be arbitrarily selected.

Examples of the polymer component (a) include polyvinyl acetal, acrylic resin (resin having a (meth) acryloyl group), and the like.

In the present specification, "(meth) acryloyl" is a concept including both "acryloyl" and "methacryloyl". The same applies to terms similar to (meth) acryloyl groups. For example, "(meth) acrylic acid" includes both the concepts of "acrylic acid" and "methacrylic acid", and "(meth) acrylate" includes both the concepts of "acrylate" and "methacrylate".

The polyvinyl acetal in the polymer component (a) may be a known polyvinyl acetal.

Among these, preferable polyvinyl acetals include, for example, polyvinyl formal and polyvinyl butyral, and more preferably polyvinyl butyral.

Examples of the polyvinyl butyral include polyvinyl butyrals having structural units represented by the following formulae (i) -1, (i) -2, and (i) -3.

[ chemical formula 1]

Wherein l, m and n are each independently an integer of 1 or more.

The weight average molecular weight (Mw) of the polyvinyl acetal is preferably 100000 or less, more preferably 70000 or less, and particularly preferably 40000 or less. By making the weight average molecular weight of the polyvinyl acetal to be in the above range, the effect of suppressing the first protective film residue from remaining on the overhead portion of the bump becomes higher.

The lower limit of the weight average molecular weight of the polyvinyl acetal is not particularly limited. However, from the viewpoint of further improving the strength and heat resistance of the first protective film, the weight average molecular weight of the polyvinyl acetal is preferably 5000 or more, and more preferably 8000 or more.

The weight average molecular weight of the polyvinyl acetal can be appropriately adjusted within a range set by arbitrarily combining any of the lower limit and the upper limit.

For example, in one embodiment, the polyvinyl acetal has a weight average molecular weight of preferably 5000 to 100000, more preferably 5000 to 70000, and particularly preferably 5000 to 40000. In one embodiment, the weight average molecular weight of the polyvinyl acetal is preferably 8000 to 100000, and more preferably 8000 to 70000. Particularly preferably 8000 to 40000. However, these ranges are only one example of a preferred weight average molecular weight of the polyvinyl acetal.

The glass transition temperature (Tg) of the polyvinyl acetal is preferably 40 to 80 ℃, more preferably 50 to 70 ℃. By making Tg of the polyvinyl acetal in the above range, the effect of suppressing the first protective film residue from remaining on the top of the head of the bump becomes higher.

The ratio of 3 or more monomers constituting the polyvinyl acetal can be arbitrarily selected.

As the acrylic resin in the polymer component (a), a known acrylic polymer can be mentioned.

The weight average molecular weight (Mw) of the acrylic resin is preferably 300000 or less, more preferably 150000 or less, and particularly preferably 100000 or less. By making the weight average molecular weight of the acrylic resin the above range, the effect of suppressing the first protective film residue from remaining on the overhead portion of the bump becomes higher.

The lower limit of the weight average molecular weight of the acrylic resin is not particularly limited. However, from the viewpoint of further improving the strength and heat resistance of the first protective film, the weight average molecular weight of the acrylic resin is preferably 10000 or more, and more preferably 30000 or more.

The weight average molecular weight of the acrylic resin can be appropriately adjusted within a range set by arbitrarily combining any of the lower limit and the upper limit.

For example, in one embodiment, the weight average molecular weight of the acrylic resin is preferably 10000 to 300000, more preferably 10000 to 150000, and particularly preferably 10000 to 100000. In one embodiment, the weight average molecular weight of the acrylic resin is preferably 30000 to 300000, more preferably 30000 to 150000, and particularly preferably 30000 to 100000. However, these ranges are only one example of the preferred weight average molecular weight of the acrylic resin.

The glass transition temperature (Tg) of the acrylic resin is preferably-50 to 70 ℃, more preferably-30 to 60 ℃. By making Tg of the acrylic resin in the above range, the effect of suppressing the first protective film residue from remaining on the tops of the heads of the bumps becomes higher.

The acrylic resin may be composed of only one monomer, or two or more monomers, and when two or more monomers are used, the combination and ratio thereof may be arbitrarily selected.

Examples of the acrylic resin include polymers of one or two or more kinds of (meth) acrylic acid esters;

copolymers of two or more monomers selected from (meth) acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, and N-methylolacrylamide;

and copolymers of one or more (meth) acrylic acid esters with one or more monomers selected from (meth) acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, and N-methylolacrylamide.

Examples of the (meth) acrylic ester constituting the acrylic resin include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, n-octyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, dodecyl (meth) acrylate, and the like, Alkyl (meth) acrylates having a chain structure in which the alkyl group constituting the alkyl ester is a carbon number of 1 to 18, such as tetradecyl (meth) acrylate (myristyl (meth) acrylate), pentadecyl (meth) acrylate, hexadecyl (meth) acrylate (palmityl (meth) acrylate), heptadecyl (meth) acrylate, and octadecyl (meth) acrylate (stearyl (meth) acrylate);

cycloalkyl (meth) acrylates such as isobornyl (meth) acrylate and dicyclopentanyl (meth) acrylate;

aralkyl (meth) acrylates such as benzyl (meth) acrylate;

cycloalkenyl (meth) acrylates such as dicyclopentenyl (meth) acrylate;

cycloalkenyloxyalkyl (meth) acrylates such as dicyclopentenyloxyethyl (meth) acrylate;

(meth) acrylic acid imide;

glycidyl group-containing (meth) acrylates such as glycidyl (meth) acrylate;

hydroxyl group-containing (meth) acrylates such as hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, and 4-hydroxybutyl (meth) acrylate;

and substituted amino group-containing (meth) acrylates such as N-methylaminoethyl (meth) acrylate. The "substituted amino group" refers to a group in which 1 or 2 hydrogen atoms of an amino group are substituted with a group other than a hydrogen atom.

The acrylic resin may have a functional group capable of bonding with other compounds, such as a vinyl group, (meth) acryloyl group, amino group, hydroxyl group, carboxyl group, and isocyanate group. The functional group of the acrylic resin may be bonded to another compound via a crosslinking agent (F) described later, or may be directly bonded to another compound without via the crosslinking agent (F). The acrylic resin is bonded to another compound through the functional group, and thus the reliability of the package obtained using the first protective film tends to be improved.

In the resin layer forming composition (III), the content of the polymer component (a) is preferably 5 to 25% by mass, and more preferably 5 to 15% by mass, relative to the total content of all components except the solvent (i.e., the content of the polymer component (a) in the thermosetting resin film), regardless of the type of the polymer component (a).

[ thermosetting component (B) ]

The thermosetting component (B) is a component that forms a hard first protective film by curing the thermosetting resin film by using heat as a cause of reaction (trigger).

The thermosetting component (B) contained in the resin layer forming composition (III) and the thermosetting resin film may be one kind only, or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

The thermosetting component (B) is preferably an epoxy thermosetting resin.

(epoxy thermosetting resin)

The epoxy thermosetting resin is composed of an epoxy resin (B1) and a thermosetting agent (B2).

The epoxy thermosetting resin contained in the resin layer forming composition (III) and the thermosetting resin film may be one kind only, or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

Epoxy resin (B1)

Examples of the epoxy resin (B1) include known epoxy resins, and examples thereof include polyfunctional epoxy resins, biphenyl compounds, bisphenol a diglycidyl ether and hydrogenated products thereof, o-cresol novolac epoxy resins, dicyclopentadiene epoxy resins, biphenyl epoxy resins, bisphenol a epoxy resins, bisphenol F epoxy resins, and epoxy resins having a phenylene skeleton.

The epoxy resin (B1) may be an epoxy resin having an unsaturated hydrocarbon group. The compatibility of the epoxy resin having an unsaturated hydrocarbon group with the acrylic resin is higher than that of the epoxy resin having no unsaturated hydrocarbon group with the acrylic resin. Therefore, the reliability of the package obtained by using the first protective film containing the epoxy resin having an unsaturated hydrocarbon group and the acrylic resin is improved.

Examples of the epoxy resin having an unsaturated hydrocarbon group include compounds obtained by converting a part of epoxy groups of a polyfunctional epoxy resin into a group having an unsaturated hydrocarbon group. The compound can be obtained, for example, by addition reaction of (meth) acrylic acid or a derivative thereof with an epoxy group.

Examples of the epoxy resin having an unsaturated hydrocarbon group include compounds in which a group having an unsaturated hydrocarbon group is directly bonded to an aromatic ring or the like constituting the epoxy resin.

The unsaturated hydrocarbon group is a polymerizable unsaturated group, and specific examples thereof include an ethylene group (vinyl group), a 2-propenyl group (allyl group), (meth) acryloyl group, and (meth) acrylamido group, with acryloyl group being preferred.

The weight average molecular weight of the epoxy resin (B1) is preferably 30000 or less, more preferably 20000 or less, and particularly preferably 10000 or less. By making the weight average molecular weight of the epoxy resin (B1) be the upper limit value or less, the effect of suppressing the first protective film residue from remaining on the overhead portion of the bump becomes higher.

The lower limit of the weight average molecular weight of the epoxy resin (B1) is not particularly limited. However, in order to further improve curability of the thermosetting resin film and strength and heat resistance of the first protective film, the weight average molecular weight of the epoxy resin (B1) is preferably 300 or more, and more preferably 500 or more.

The weight average molecular weight of the epoxy resin (B1) can be appropriately adjusted within a range set by arbitrarily combining any of the lower limit and the upper limit.

For example, in one embodiment, the weight average molecular weight of the epoxy resin (B1) is preferably 300 to 30000, more preferably 300 to 20000, and particularly preferably 300 to 10000. In one embodiment, the weight average molecular weight of the epoxy resin (B1) is preferably 500 to 30000, more preferably 500 to 20000, and particularly preferably 500 to 10000. However, these ranges are only one example of a preferred weight average molecular weight of the epoxy resin (B1).

The epoxy equivalent of the epoxy resin (B1) is preferably 100 to 1000g/eq, more preferably 300 to 800 g/eq.

The epoxy resin (B1) is preferably in a liquid state at room temperature (in this specification, it may be simply referred to as "liquid epoxy resin (B1)"). By using the above epoxy resin (B1), the effect of suppressing the first protective film residue from remaining on the crown portion of the bump becomes higher.

The epoxy resin (B1) may be used alone or in combination of two or more, and when two or more are used simultaneously, the combination and ratio thereof may be arbitrarily selected.

In the epoxy resin (B1) contained in the resin layer-forming composition (III) and the thermosetting resin film, the proportion of the liquid epoxy resin (B1) is preferably 40% by mass or more, more preferably 50% by mass or more, particularly preferably 55% by mass or more, and may be, for example, any one of 60% by mass or more, 70% by mass or more, 80% by mass or more, and 90% by mass or more. By making the ratio the lower limit value or more, the effect of suppressing the first protective film residue from remaining on the crown portion of the bump becomes higher.

The upper limit of the ratio is not particularly limited, and the ratio may be 100 mass% or less.

Heat-curing agent (B2)

The thermosetting agent (B2) functions as a curing agent for the epoxy resin (B1).

Examples of the thermosetting agent (B2) include compounds having two or more functional groups reactive with an epoxy group in one molecule. Examples of the functional group include a phenolic hydroxyl group, an alcoholic hydroxyl group, an amino group, a carboxyl group, and a group obtained by anhydrizing an acid group, and the like, and a phenolic hydroxyl group, an amino group, or a group obtained by anhydrizing an acid group are preferable, and a phenolic hydroxyl group or an amino group is more preferable.

Examples of the phenol curing agent having a phenolic hydroxyl group in the thermal curing agent (B2) include polyfunctional phenol resins, biphenol, novolak-type phenol resins, dicyclopentadiene-type phenol resins, and aralkyl phenol resins.

Examples of the amine-based curing agent having an amino group in the thermosetting agent (B2) include dicyandiamide (hereinafter, this may be abbreviated as "DICY").

The thermosetting agent (B2) may have an unsaturated hydrocarbon group.

Examples of the unsaturated hydrocarbon group-containing thermosetting agent (B2) include a compound in which a part of the hydroxyl groups of the phenol resin is substituted with an unsaturated hydrocarbon group-containing group, a compound in which an unsaturated hydrocarbon group-containing group is directly bonded to an aromatic ring of the phenol resin, and the like.

The unsaturated hydrocarbon group in the thermosetting agent (B2) is the same as the unsaturated hydrocarbon group in the above-mentioned epoxy resin having an unsaturated hydrocarbon group.

The number average molecular weight of the resin component of the heat-curing agent (B2), such as a polyfunctional phenol resin, a novolak-type phenol resin, a dicyclopentadiene-type phenol resin, or an aralkyl phenol resin, is preferably 300 to 30000, more preferably 400 to 10000, and particularly preferably 500 to 5000.

The molecular weight of the non-resin component such as biphenol and dicyandiamide in the thermosetting agent (B2) is not particularly limited, and is preferably 60 to 500, for example.

The heat-curing agent (B2) may be used alone or in combination of two or more, and when two or more are used simultaneously, the combination and ratio thereof may be arbitrarily selected.

In the resin layer-forming composition (III) and the thermosetting resin film, the content of the thermosetting agent (B2) is preferably 0.1 to 500 parts by mass, more preferably 1 to 200 parts by mass, and may be, for example, any one of 1 to 150 parts by mass, 1 to 100 parts by mass, 1 to 75 parts by mass, 1 to 50 parts by mass, and 1 to 30 parts by mass, based on 100 parts by mass of the content of the epoxy resin (B1). By setting the content of the thermosetting agent (B2) to the lower limit or more, it becomes easier to cure the thermosetting resin film. Further, by setting the content of the thermosetting agent (B2) to the upper limit or less, the moisture absorption rate of the thermosetting resin film is reduced, and the reliability of the package obtained using the first protective film is further improved.

In the resin layer-forming composition (III) and the thermosetting resin film, the content of the thermosetting component (B) (for example, the total content of the epoxy resin (B1) and the thermosetting agent (B2)) is preferably 600 to 1000 parts by mass with respect to 100 parts by mass of the content of the polymer component (a). By making the content of the thermosetting component (B) in the above range, the effect of suppressing the first protective film residue from remaining on the tops of the heads of the bumps becomes higher, and a hard first protective film can be formed.

Further, from the point that the above-described effects are more remarkably obtained, the content of the thermosetting component (B) is preferably appropriately adjusted depending on the kind of the polymer component (a).

For example, when the polymer component (a) is the polyvinyl acetal, the content of the thermosetting component (B) in the resin layer-forming composition (III) and the thermosetting resin film is preferably 600 to 1000 parts by mass, more preferably 650 to 1000 parts by mass, and particularly preferably 650 to 950 parts by mass, relative to 100 parts by mass of the content of the polymer component (a).

For example, when the polymer component (a) is the acrylic resin, the content of the thermosetting component (B) in the resin layer-forming composition (III) and the thermosetting resin film is preferably 700 to 1000 parts by mass, more preferably 750 to 1000 parts by mass, and particularly preferably 750 to 900 parts by mass, relative to 100 parts by mass of the content of the polymer component (a).

[ curing Accelerator (C) ]

The resin layer forming composition (III) and the thermosetting resin film preferably contain a curing accelerator (C). The curing accelerator (C) is a component for adjusting the curing rate of the resin layer forming composition (III).

Examples of the preferable curing accelerator (C) include tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris (dimethylaminomethyl) phenol; imidazoles (imidazole in which 1 or more hydrogen atoms are replaced with a group other than a hydrogen atom) such as 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4, 5-dihydroxymethylimidazole, and 2-phenyl-4-methyl-5-hydroxymethylimidazole; organophosphines (phosphines in which 1 or more hydrogen atoms are substituted with an organic group), such as tributylphosphine, diphenylphosphine, and triphenylphosphine; tetraphenylboron salts such as tetraphenylphosphonium tetraphenylborate and triphenylphosphine tetraphenylboron ester.

The curing accelerator (C) contained in the resin layer forming composition (III) and the thermosetting resin film may be one kind or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

When the curing accelerator (C) is used, the content of the curing accelerator (C) is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass, relative to 100 parts by mass of the content of the thermosetting component (B) in the resin layer-forming composition (III) and the thermosetting resin film. By setting the content of the curing accelerator (C) to the lower limit or more, the effect of using the curing accelerator (C) can be more remarkably obtained. Further, when the content of the curing accelerator (C) is not more than the upper limit, for example, the effect of suppressing the occurrence of segregation of the highly polar curing accelerator (C) in the thermosetting resin film by moving to the side of the adhesive interface with the adherend under the high temperature-high humidity condition becomes high, and the reliability of the package obtained using the first protective film is further improved.

[ Filler (D) ]

The resin layer forming composition (III) and the thermosetting resin film preferably contain a filler (D). The first protective film containing the filler (D) easily adjusts the thermal expansion coefficient. For example, by optimizing the thermal expansion coefficient of the first protection film with respect to the semiconductor chip, the reliability of the package obtained using the first protection film is further improved. In addition, the first protective film containing the filler (D) can reduce the moisture absorption rate and improve the heat release property.

The filler (D) may be any of an organic filler and an inorganic filler, and is preferably an inorganic filler.

Examples of preferable inorganic fillers include powders of silica, alumina, talc, calcium carbonate, titanium white, red iron oxide, silicon carbide, boron nitride, and the like; beads obtained by spheroidizing these inorganic fillers; surface modifications of these inorganic filler materials; single crystal fibers of these inorganic filler materials; glass fibers, and the like.

Among them, the inorganic filler is preferably silica or alumina.

The filler (D) contained in the resin layer forming composition (III) and the thermosetting resin film may be one kind or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

The average particle diameter of the filler (D) is preferably 6 μm or less, and may be, for example, any one of 4 μm or less, 2 μm or less, and 0.5 μm or less. By making the average particle diameter of the filler (D) the upper limit value or less, the effect of suppressing the first protective film residue from remaining on the tops of the heads of the bumps becomes higher.

In the present specification, unless otherwise specified, "average particle diameter" refers to the particle diameter (D) at which the cumulative value is 50% in the particle size distribution curve obtained by the laser refraction diffraction method₅₀) The value of (c).

The lower limit of the average particle size of the filler (D) is not particularly limited, and for example, the average particle size of the filler (D) is preferably 0.01 μm or more, as determined from the point that the filler (D) is more easily obtained.

The average particle diameter of the filler (D) can be appropriately adjusted within a range set by arbitrarily combining any of the lower limit values and any of the upper limit values.

For example, the average particle diameter of the filler (D) is preferably 0.01 to 6 μm, and may be, for example, any one of 0.01 to 4 μm, 0.01 to 2 μm, and 0.01 to 0.5 μm. However, these ranges are only one example of a preferred average particle size of the filler material (D).

On the other hand, when the filler (D) is used, the proportion of the content of the filler (D) to the total content of all the components except the solvent (i.e., the proportion of the content of the filler (D) in the thermosetting resin film to the total mass of the thermosetting resin film) in the resin layer forming composition (III) is more preferably 3 to 30 mass%, still more preferably 4 to 20 mass%, and particularly preferably 5 to 15 mass%. By making the content of the filler (D) in the above range, the effect of suppressing the first protective film residue from remaining on the top of the head of the bump becomes higher, and at the same time, it is easier to adjust the above thermal expansion coefficient.

[ coupling agent (E) ]

The resin layer forming composition (III) and the thermosetting resin film may contain a coupling agent (E). By using a substance having a functional group capable of reacting with an inorganic compound or an organic compound as the coupling agent (E), the adhesiveness and adhesiveness of the thermosetting resin film to an adherend can be improved. Further, the first protective film containing the coupling agent (E) is improved in water resistance without impairing heat resistance.

The coupling agent (E) is preferably a compound having a functional group capable of reacting with a functional group of the polymer component (a), the thermosetting component (B), or the like, and more preferably a silane coupling agent.

Examples of the preferable silane coupling agent include 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxymethyldiethoxysilane, 2- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3- (2-aminoethylamino) propyltrimethoxysilane, 3- (2-aminoethylamino) propylmethyldiethoxysilane, 3- (phenylamino) propyltrimethoxysilane, 3-anilinopropyltrimethoxysilane, 3-ureopropyltriethoxysilane, 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropyltriethoxysilane, and the like, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, bis (3-triethoxysilylpropyl) tetrasulfide, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, imidazolesilane and the like.

The coupling agent (E) contained in the resin layer forming composition (III) and the thermosetting resin film may be one kind only, or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

When the coupling agent (E) is used, the content of the coupling agent (E) is preferably 0.03 to 20 parts by mass, more preferably 0.05 to 10 parts by mass, and particularly preferably 0.1 to 5 parts by mass, based on 100 parts by mass of the total content of the polymer component (a) and the thermosetting component (B), in the resin layer-forming composition (III) and the thermosetting resin film. When the content of the coupling agent (E) is not less than the lower limit, the effects of improving the dispersibility of the filler (D) in the resin and improving the adhesion between the thermosetting resin film and the adherend, which are brought about by the use of the coupling agent (E), can be more remarkably obtained. Further, by setting the content of the coupling agent (E) to the upper limit value or less, the generation of degassing is further suppressed.

[ crosslinking agent (F) ]

When a component having a functional group capable of bonding with other compounds, such as a vinyl group, (meth) acryloyl group, amino group, hydroxyl group, carboxyl group, or isocyanate group, is used as the polymer component (a), the resin layer forming composition (III) and the thermosetting resin film may contain a crosslinking agent (F). The crosslinking agent (F) is a component for bonding and crosslinking the functional group in the polymer component (a) with another compound, and by thus crosslinking, the initial adhesive force and cohesive force of the thermosetting resin film can be adjusted.

Examples of the crosslinking agent (F) include an organic polyisocyanate compound, an organic polyimine compound, a metal chelate crosslinking agent (a crosslinking agent having a metal chelate structure), an aziridine crosslinking agent (a crosslinking agent having an aziridine group), and the like.

Examples of the organic polyisocyanate compound include an aromatic polyisocyanate compound, an aliphatic polyisocyanate compound, and an alicyclic polyisocyanate compound (hereinafter, these compounds may be collectively abbreviated as "aromatic polyisocyanate compound, etc.); trimers, isocyanurate bodies and adducts of the aromatic polyisocyanate compounds and the like; and isocyanate-terminated urethane prepolymers obtained by reacting the aromatic polyisocyanate compound and the like with a polyol compound. The "adduct" refers to a reactant of the aromatic polyisocyanate compound, aliphatic polyisocyanate compound or alicyclic polyisocyanate compound with a low-molecular active hydrogen-containing compound such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane or castor oil. Examples of the adduct include xylylene diisocyanate adducts of trimethylolpropane described later. Further, the "isocyanate-terminated urethane prepolymer" is as described above.

More specific examples of the organic polyisocyanate compound include 2, 4-tolylene diisocyanate; 2, 6-toluene diisocyanate; 1, 3-xylylene diisocyanate; 1, 4-xylene diisocyanate; diphenylmethane-4, 4' -diisocyanate; diphenylmethane-2, 4' -diisocyanate; 3-methyl diphenylmethane diisocyanate; hexamethylene diisocyanate; isophorone diisocyanate; dicyclohexylmethane-4, 4' -diisocyanate; dicyclohexylmethane-2, 4' -diisocyanate; a compound obtained by adding one or more of tolylene diisocyanate, hexamethylene diisocyanate and xylylene diisocyanate to all or a part of the hydroxyl groups of a polyol such as trimethylolpropane; lysine diisocyanate, and the like.

Examples of the organic polyimine compound include N, N ' -diphenylmethane-4, 4 ' -bis (1-aziridinecarboxamide), trimethylolpropane-tris- β -aziridinylpropionate, tetramethylolmethane-tris- β -aziridinylpropionate, and N, N ' -toluene-2, 4-bis (1-aziridinecarboxamide) triethylenemelamine.

When an organic polyisocyanate compound is used as the crosslinking agent (F), a hydroxyl group-containing polymer is preferably used as the polymer component (A). When the crosslinking agent (F) has an isocyanate group and the polymer component (a) has a hydroxyl group, a crosslinked structure can be easily introduced into the thermosetting resin film by the reaction of the crosslinking agent (F) with the polymer component (a).

The crosslinking agent (F) contained in the resin layer forming composition (III) and the thermosetting resin film may be one kind only, or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

When the crosslinking agent (F) is used, the content of the crosslinking agent (F) is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 10 parts by mass, and particularly preferably 0.5 to 5 parts by mass, based on 100 parts by mass of the polymer component (a) in the resin layer-forming composition (III) and the thermosetting resin film. By setting the content of the crosslinking agent (F) to the lower limit or more, the effect of using the crosslinking agent (F) can be more remarkably obtained. Further, by making the content of the crosslinking agent (F) the upper limit value or less, the excessive use of the crosslinking agent (F) is suppressed.

[ energy ray-curable resin (G) ]

The resin layer forming composition (III) and the thermosetting resin film may contain an energy ray-curable resin (G). The thermosetting resin film contains the energy ray-curable resin (G), and the properties thereof can be changed by irradiation with an energy ray.

The energy ray-curable resin (G) is obtained by polymerizing (curing) an energy ray-curable compound.

Examples of the energy ray-curable compound include compounds having at least 1 polymerizable double bond in the molecule, and acrylate compounds having a (meth) acryloyl group are preferable.

Examples of the acrylic ester-based compound include (meth) acrylates having a chain-like aliphatic skeleton such as trimethylolpropane tri (meth) acrylate, tetramethylolmethane tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol monohydroxypenta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1, 4-butanediol di (meth) acrylate, and 1, 6-hexanediol di (meth) acrylate; cyclic aliphatic skeleton-containing (meth) acrylates such as dicyclopentyl di (meth) acrylate; polyalkylene glycol (meth) acrylates such as polyethylene glycol di (meth) acrylate; an oligoester (meth) acrylate; a urethane (meth) acrylate oligomer; epoxy-modified (meth) acrylates; a polyether (meth) acrylate other than the polyalkylene glycol (meth) acrylate; itaconic acid oligomers, and the like.

The weight average molecular weight of the energy ray-curable compound is preferably 100 to 30000, more preferably 300 to 10000.

The energy ray-curable compound used for polymerization may be one kind only, or two or more kinds, and in the case of two or more kinds, a combination and a ratio thereof may be arbitrarily selected.

The energy ray-curable resin (G) contained in the resin layer-forming composition (III) and the thermosetting resin film may be one kind only, or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

When the energy ray-curable resin (G) is used, the content of the energy ray-curable resin (G) in the resin layer-forming composition (III) is preferably 1 to 95% by mass, more preferably 5 to 90% by mass, and particularly preferably 10 to 85% by mass, based on the total mass of the resin layer-forming composition (III).

[ photopolymerization initiator (H) ]

When the resin layer forming composition (III) and the thermosetting resin film contain the energy ray-curable resin (G), a photopolymerization initiator (H) may be contained in order to effectively advance the polymerization reaction of the energy ray-curable resin (G).

Examples of the photopolymerization initiator (H) in the resin layer forming composition (III) include benzoin compounds such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, benzoin methyl benzoate and benzoin dimethyl ketal, acetophenone compounds such as acetophenone, 2-hydroxy-2-methyl-1-phenyl-propane-1-one and 2, 2-dimethoxy-1, 2-diphenylethane-1-one, acyl phosphine oxide compounds such as phenyl bis (2,4, 6-trimethylbenzoyl) phosphine oxide and 2,4, 6-trimethylbenzoyl diphenylphosphine oxide, sulfides such as benzyl phenyl sulfide and tetramethylthiuram monosulfide, α -ketol compounds such as 1-hydroxycyclohexyl phenyl ketone, azo compounds such as azobisisobutyronitrile, titanocene compounds such as titanocene, thioxanthone such as 2, 4-diethylthioxanthone, thioxanthone compounds such as peroxide, benzoin compounds such as 2-succinyl benzophenone, 2- (2-methyl) acetone, 2- (2-chlorobutyryl) acetone, 2- (2-methyl) methyl-2-methyl-benzoine, and the like.

Further, as the photopolymerization initiator (H), for example, quinone compounds such as 1-chloroanthraquinone; photosensitizers such as amines, and the like.

The photopolymerization initiator (H) contained in the resin layer forming composition (III) and the thermosetting resin film may be one kind or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

When the photopolymerization initiator (H) is used, the content of the photopolymerization initiator (H) is preferably 0.1 to 20 parts by mass, more preferably 1 to 10 parts by mass, and particularly preferably 2 to 5 parts by mass, relative to 100 parts by mass of the content of the energy ray-curable resin (G) in the resin layer-forming composition (III) and the thermosetting resin film.

[ colorant (I) ]

The resin layer forming composition (III) and the thermosetting resin film may not contain the colorant (I). The colorant (I) is, for example, a component for imparting appropriate light transmittance to the thermosetting resin film and the first protective film.

The colorant (I) may be a known component, and may be, for example, any of a dye and a pigment.

For example, the dye may be any of an acid dye, a reactive dye, a direct dye, a disperse dye, a cationic dye, and the like,

the colorant (I) contained in the resin layer forming composition (III) and the thermosetting resin film may be one kind only, or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

When the colorant (I) is used, the content of the colorant (I) in the resin layer forming composition (III) is not particularly limited as long as it is appropriately adjusted so that the visible light transmittance and the infrared transmittance of the thermosetting resin film become target values. For example, the content of the colorant (I) may be appropriately adjusted depending on the kind of the colorant (I), or a combination of two or more colorants (I) when these colorants (I) are used simultaneously.

When the colorant (I) is used, in general, in the resin layer forming composition (III), the ratio of the content of the colorant (I) to the total content of all the components except the solvent (i.e., the ratio of the content of the colorant (I) in the thermosetting resin film to the total mass of the thermosetting resin film) is preferably 0.01 to 10% by mass.

[ general additive (J) ]

The resin layer forming composition (III) and the thermosetting resin film may contain a general-purpose additive (J) within a range not to impair the effects of the present invention.

The general-purpose additive (J) may be a known component, may be arbitrarily selected according to the purpose, and is not particularly limited, and preferable additives include, for example, a plasticizer, an antistatic agent, an antioxidant, and a gettering agent (gelling agent).

The general-purpose additive (J) contained in the resin layer forming composition (III) and the thermosetting resin film may be one kind or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

The content of the general-purpose additive (J) in the resin layer forming composition (III) and the thermosetting resin film is not particularly limited, and may be appropriately selected according to the purpose.

[ solvent ]

The resin layer forming composition (III) preferably further contains a solvent. The composition (III) for forming a resin layer containing a solvent has good workability.

The solvent is not particularly limited, but preferable examples thereof include hydrocarbons such as toluene and xylene; alcohols such as methanol, ethanol, 2-propanol, isobutanol (2-methylpropane-1-ol), and 1-butanol; esters such as ethyl acetate; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran; amides (compounds having an amide bond) such as dimethylformamide and N-methylpyrrolidone.

The amount of the solvent contained in the resin layer forming composition (III) may be one kind or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

The solvent contained in the resin layer forming composition (III) is preferably methyl ethyl ketone or the like, since the components contained in the resin layer forming composition (III) can be mixed more uniformly.

The content of the solvent in the resin layer forming composition (III) is not particularly limited, and may be appropriately selected depending on the kind of components other than the solvent, for example.

The resin layer forming composition (III) and the thermosetting resin film contain the polymer component (a) and the thermosetting component (B), preferably contain polyvinyl acetal as the polymer component (a), and contain an epoxy resin that is liquid at normal temperature as the epoxy resin (B1), and more preferably further contain a curing accelerator (C) and a filler (D) in addition to these components. In this case, the filler (D) preferably has the above-mentioned average particle diameter. By using the above resin layer forming composition (III) and thermosetting resin film, the effect of suppressing the first protective film residue from remaining on the tops of the heads of the bumps becomes higher.

As a preferred embodiment of the resin layer forming composition (III), for example, there is a resin layer forming composition (III) containing a polymer component (a) which is polyvinyl acetal, an epoxy resin (B1) which is liquid at ordinary temperature, a thermosetting agent (B2), a curing accelerator (C), and a filler (D), wherein the total content of the epoxy resin (B1) and the thermosetting agent (B2) is 600 to 1000 parts by mass with respect to 100 parts by mass of the content of the polymer component (a), the content of the curing accelerator (C) is 0.1 to 5 parts by mass with respect to 100 parts by mass of the total content of the epoxy resin (B1) and the thermosetting agent (B2), and the content of the filler (D) is 3 to 30 parts by mass with respect to the total content of all components except a solvent in the resin layer forming composition (III), the filler (D) has an average particle diameter of 6 μm or less.

A more preferred embodiment of the resin layer forming composition (III) includes, for example, a resin layer forming composition (III) containing a polymer component (a) which is polyvinyl acetal having a weight average molecular weight of 40000 or less, an epoxy resin (B1) which is liquid at ordinary temperature, a thermosetting agent (B2), a curing accelerator (C) and a filler (D), the epoxy resin (B1) having a weight average molecular weight of 10000 or less, wherein the total content of the epoxy resin (B1) and the thermosetting agent (B2) is 600 to 1000 parts by mass relative to 100 parts by mass of the content of the polymer component (a) in the resin layer forming composition (III), and the content of the curing accelerator (C) is 0.1 to 5 parts by mass relative to 100 parts by mass of the total content of the epoxy resin (B1) and the thermosetting agent (B2), and in the resin layer forming composition (III), the content of the filler (D) is 5-15 mass% relative to the total content of all the components except the solvent, and the average particle diameter of the filler (D) is less than 2 μm.

◎ method for producing composition for forming thermosetting resin film

The thermosetting resin film-forming composition such as the resin layer-forming composition (III) can be obtained by blending the respective components constituting the composition.

The order of addition of the components in blending is not particularly limited, and two or more components may be added simultaneously.

When a solvent is used, the solvent may be mixed with any of the components other than the solvent to preliminarily dilute the components, or the solvent may be mixed with the components without preliminarily diluting any of the components other than the solvent to use the mixture.

The method for mixing the components at the time of blending is not particularly limited, and may be appropriately selected from the following known methods: a method of mixing by rotating a stirrer, a stirring blade, or the like; a method of mixing using a mixer (mixer); a method of mixing by applying ultrasonic waves, and the like.

The temperature and time when the components are added and mixed are not particularly limited as long as the components are not deteriorated, and may be appropriately adjusted, but the temperature is preferably 15 to 30 ℃.

◎ composition for forming energy ray-curable resin film

○ composition for Forming resin layer (IV)

Examples of the energy ray-curable resin film-forming composition include an energy ray-curable resin film-forming composition (IV) containing an energy ray-curable component (a) (in the present specification, this may be abbreviated as "resin layer-forming composition (IV)").

[ energy ray-curable component (a) ]

The energy ray-curable component (a) is a component which is cured by irradiation with an energy ray, and is used for imparting film formability, flexibility, or the like to an energy ray-curable resin film.

Examples of the energy ray-curable component (a) include a polymer (a1) having an energy ray-curable group and a weight average molecular weight of 80000 to 2000000, and a compound (a2) having an energy ray-curable group and a molecular weight of 100 to 80000. At least a portion of the polymer (a1) may or may not be crosslinked by a crosslinking agent.

Examples of the polymer (a1) having an energy ray-curable group and a weight average molecular weight of 80000 to 2000000 include an acrylic resin (a1-1) obtained by polymerizing an acrylic polymer (a11) having a functional group capable of reacting with a group of another compound and an energy ray-curable compound (a12) having an energy ray-curable group such as a group reactive with the functional group and an energy ray-curable double bond.

Examples of the functional group capable of reacting with a group of another compound include a hydroxyl group, a carboxyl group, an amino group, a substituted amino group (a group in which 1 or 2 hydrogen atoms of the amino group are substituted with a group other than a hydrogen atom), an epoxy group, and the like. However, the functional group is preferably a group other than a carboxyl group from the viewpoint of preventing corrosion of circuits of a semiconductor wafer, a semiconductor chip, or the like.

Among them, the functional group is preferably a hydroxyl group.

Examples of the acrylic polymer (a11) having the functional group include polymers obtained by copolymerizing an acrylic monomer having the functional group and an acrylic monomer having no functional group, and polymers obtained by copolymerizing a monomer other than the acrylic monomer (non-acrylic monomer) in addition to these monomers.

The acrylic polymer (a11) may be a random copolymer or a block copolymer.

In the acrylic polymer (a11), the acrylic monomer having the functional group, the acrylic monomer not having the functional group, and the non-acrylic monomer may be used alone or in combination of two or more, and when two or more are used simultaneously, the combination and ratio thereof may be arbitrarily selected.

The energy ray-curable compound (a12) preferably has one or more selected from the group consisting of an isocyanate group, an epoxy group and a carboxyl group as a group capable of reacting with a functional group of the acrylic polymer (a11), and more preferably has an isocyanate group as the group. For example, when the energy ray-curable compound (a12) has an isocyanate group as the group, the isocyanate group easily reacts with a hydroxyl group of the acrylic polymer (a11) having the hydroxyl group as the functional group.

Examples of the energy ray-curable group in the compound (a2) having an energy ray-curable group and a molecular weight of 100 to 80000 include groups containing an energy ray-curable double bond, and preferable examples thereof include a (meth) acryloyl group, a vinyl group and the like.

[ Polymer (b) having no energy ray-curable group ]

When the resin layer forming composition (IV) and the energy ray-curable resin film contain the compound (a2) as the energy ray-curable component (a), it is preferable that the composition further contains a polymer (b) having no energy ray-curable group.

At least a portion of the polymer (b) may or may not be crosslinked by a crosslinking agent.

Examples of the polymer (b) having no energy ray-curable group include acrylic polymers, phenoxy resins, urethane resins, polyesters, rubber resins, and acrylic urethane resins.

Among them, the polymer (b) is preferably an acrylic polymer (in the present specification, it may be referred to as "acrylic polymer (b-1)").

Examples of the resin layer forming composition (IV) include a composition containing either one or both of the polymer (a1) and the compound (a 2). When the resin layer forming composition (IV) contains the compound (a2), it preferably further contains a polymer (b) having no energy ray-curable group, and in this case, it preferably further contains the polymer (a 1). Further, the resin layer forming composition (IV) may contain the polymer (a1) and the polymer (b) having no energy ray-curable group, in addition to the compound (a 2).

In the resin layer-forming composition (IV), the energy ray-curable component (a) and the polymer (b) having no energy ray-curable group may be used singly or in combination of two or more, and when two or more are used simultaneously, the combination and ratio thereof may be arbitrarily selected.

When the resin layer forming composition (IV) contains the polymer (a1), the compound (a2), and the polymer (b) having no energy ray-curable group, the content of the compound (a2) in the resin layer forming composition (IV) is preferably 10 to 400 parts by mass relative to 100 parts by mass of the total content of the polymer (a1) and the polymer (b) having no energy ray-curable group.

In the resin layer-forming composition (IV), the ratio of the total content of the energy ray-curable component (a) and the polymer (b) having no energy ray-curable group to the total content of components other than the solvent (i.e., the ratio of the total content of the energy ray-curable component (a) and the polymer (b) having no energy ray-curable group to the total mass of the energy ray-curable resin film in the energy ray-curable resin film) is preferably 5 to 90% by mass.

The resin layer forming composition (IV) may contain one or more selected from the group consisting of a thermosetting component, a photopolymerization initiator, a filler, a coupling agent, a crosslinking agent, a colorant, a general-purpose additive, and a solvent, in addition to the energy ray-curable component, according to the purpose. For example, by using the composition (IV) for forming a resin layer containing the energy ray-curable component and the thermosetting component, the adhesive force to an adherend of the formed energy ray-curable resin film is enhanced by heating, and the strength of the first protective film formed from the energy ray-curable resin film is also improved.

Examples of the thermosetting component, photopolymerization initiator, filler, coupling agent, crosslinking agent, colorant, general-purpose additive and solvent in the resin layer forming composition (IV) include the same components as those of the thermosetting component (B), photopolymerization initiator (H), filler (D), coupling agent (E), crosslinking agent (F), colorant (I), general-purpose additive (J) and solvent in the resin layer forming composition (III).

In the resin layer-forming composition (IV), the thermosetting component, photopolymerization initiator, filler, coupling agent, crosslinking agent, colorant, general-purpose additive and solvent may be used singly or in combination of two or more, and when two or more are used simultaneously, the combination and ratio thereof may be arbitrarily selected.

The content of the thermosetting component, photopolymerization initiator, filler, coupling agent, crosslinking agent, colorant, general-purpose additive and solvent in the resin layer forming composition (IV) is not particularly limited as long as it is appropriately adjusted according to the purpose.

◎ method for producing composition for forming energy ray-curable resin film

The energy ray-curable resin film-forming composition such as the resin layer-forming composition (IV) can be obtained by blending the components constituting the composition.

The method for mixing the components at the time of blending is not particularly limited, and may be appropriately selected from the following known methods: a method of mixing by rotating a stirrer, a stirring blade, or the like; a method of mixing using a mixer; a method of mixing by applying ultrasonic waves, and the like.

◇ method for manufacturing semiconductor chip with first protective film

A method for manufacturing a semiconductor chip with a first protective film according to the present invention is a method for manufacturing a semiconductor chip with a first protective film, including: a step of attaching a curable resin film to a surface of a semiconductor wafer having bumps (in this specification, this may be abbreviated as "attaching step"); a step of forming a first protective film by curing the cured resin film after the application (in this specification, this may be abbreviated as "first protective film forming step"); and a step of obtaining a semiconductor chip by dividing the semiconductor wafer (in this specification, this may be abbreviated as "dividing step"), wherein in the step of attaching the curable resin film, the top portion of the bump is caused to protrude from the curable resin film so that the ratio of the tin concentration is 5% or more, or the step of attaching the curable resin film is further provided with a step of reducing the amount of residue on the bump so that the ratio of the tin concentration is 5% or more (in this specification, this may be abbreviated as "residue reducing step").

The manufacturing method is described below with reference to the drawings.

First, a method for manufacturing a semiconductor chip with a first protective film shown in fig. 1 will be described. Fig. 5 is an enlarged sectional view schematically illustrating the present embodiment.

< attaching step >

In the manufacturing method, first, the bonding step is performed to bond a curable resin film 13 'to the bump formation surface 9a of the semiconductor wafer 9', as shown in fig. 5 (a). By performing this step, the curable resin film 13' spreads among the plurality of bumps 91 present, adheres to the bump forming surface 9a, covers the surface 91a of the bump 91, particularly the surface 91a in the vicinity of the bump forming surface 9a, and embeds the bump 91, thereby covering these regions.

In this step, for example, the top portions 910 of the bumps 91 of the semiconductor wafer 9 ' penetrate the curable resin film 13 ' and protrude from the curable resin film 13 '.

In the sticking step, for example, the curable resin film 13 'alone may be used, but it is preferable to use the first protective film forming sheet 191 which is composed of the first support sheet 10 and the curable resin film 13' formed on the first support sheet 10 as shown here. By using the first protective film forming sheet 191, it is possible to suppress the occurrence of voids at any position between the curable resin film 13 'and the bump forming surface 9a and between the curable resin film 13' and the surface 91a of the bump 91. And, finally, the effect of suppressing the first protective film residue from remaining on the crown portion 910 of the bump 91 becomes higher.

In the case where the first protective film forming sheet shown here is used in the attaching step, the first protective film forming sheet itself may be attached to the bump forming surface of the semiconductor wafer by attaching the curable resin film in the first protective film forming sheet to the bump forming surface of the semiconductor wafer.

In the present specification, a structure in which the first protective film forming sheet is attached to the bump forming surface of the semiconductor wafer as described herein may be referred to as a "stacked structure (1)". Fig. 5 shows a structure in which a first protective film forming sheet 191 is attached to a bump forming surface 9a of a semiconductor wafer 9' as a laminated structure (1) 101.

In the first protective film forming sheet 191, the first support sheet 10 is configured to include the first base 11 and the buffer layer 12 formed on the first base 11. That is, the first protective film forming sheet 191 is formed by sequentially laminating the first base material 11, the buffer layer 12, and the curable resin film 13' in the thickness direction thereof.

Fig. 6 is an enlarged sectional view schematically showing the first protective film forming sheet 191.

As the first support sheet 10, a known support sheet can be used.

The first base material 11 is in the form of a sheet or a film, and examples of the material of the first base material include various resins.

Examples of the resin include polyethylene such as low density polyethylene (which may be abbreviated as LDPE), linear low density polyethylene (which may be abbreviated as LLDPE), and high density polyethylene (which may be abbreviated as HDPE); polyolefins other than polyethylene, such as polypropylene, polybutene, polybutadiene, polymethylpentene, and norbornene resins; ethylene copolymers (copolymers obtained using ethylene as a monomer) such as ethylene-vinyl acetate copolymers, ethylene- (meth) acrylic acid ester copolymers, and ethylene-norbornene copolymers; vinyl chloride-based resins (resins obtained using vinyl chloride as a monomer) such as polyvinyl chloride and vinyl chloride copolymers; polystyrene; a polycycloolefin; polyesters such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polyethylene isophthalate, polyethylene 2, 6-naphthalate, and wholly aromatic polyesters having an aromatic ring group in all the structural units; copolymers of two or more of said polyesters; poly (meth) acrylates; a polyurethane; a urethane acrylate; a polyimide; a polyamide; a polycarbonate; a fluororesin; a polyacetal; modified polyphenylene ether; polyphenylene sulfide; polysulfones; polyether ketones, and the like.

Examples of the resin include a polymer blend such as a mixture of the polyester and a resin other than the polyester. Preferably the amount of resin other than polyester in the polymeric blend of the polyester with resin other than polyester is a minor amount.

Examples of the resin include crosslinked resins obtained by crosslinking one or more of the resins exemplified above; modified resins such as ionomers using one or more of the resins described above as examples.

The resin constituting the first base material 11 may be one kind only, or two or more kinds, and in the case of two or more kinds, the combination and ratio thereof may be arbitrarily selected.

The first substrate 11 may be formed of one layer (single layer) or a plurality of layers of two or more layers, and when formed of a plurality of layers, these plurality of layers may be the same or different from each other, and the combination of these plurality of layers is not particularly limited.

The thickness of the first substrate 11 is preferably 25 to 150 μm.

Here, the "thickness of the first substrate 11" refers to the thickness of the entire first substrate 11, and for example, the thickness of the first substrate 11 formed of a plurality of layers refers to the total thickness of all the layers constituting the first substrate 11.

The buffer layer 12 has a function of buffering a force applied to the buffer layer 12 and layers adjacent thereto. Here, "as a layer adjacent to the buffer layer", a curable resin film 13' is shown.

The buffer layer 12 is sheet-shaped or film-shaped, and is preferably energy ray-curable. The energy ray-curable buffer layer 12 is more easily peeled from the curable resin film 13' described later by energy ray curing.

Examples of the material constituting the cushion layer 12 include various adhesive resins. When the buffer layer 12 is energy ray-curable, various components necessary for energy ray curing can be used as the constituent material.

The buffer layer 12 may be formed of one layer (single layer) or a plurality of layers of two or more layers, and when formed of a plurality of layers, these plurality of layers may be the same or different from each other, and the combination of these plurality of layers is not particularly limited.

The thickness of the buffer layer 12 is preferably 60 to 675 μm.

Here, the "thickness of the buffer layer 12" refers to the thickness of the entire buffer layer 12, and for example, the thickness of the buffer layer 12 formed of a plurality of layers refers to the total thickness of all the layers constituting the buffer layer 12.

In the attaching step, the thermosetting resin film 13 ' can be attached to the bump forming surface 9a of the semiconductor wafer 9 ' by pressing the exposed surface (which may be referred to as "first surface" in this specification) 13 ' a of the thermosetting resin film 13 ' on the side opposite to the semiconductor wafer 9 ' against the bump forming surface 9 a.

In the sticking step, the curable resin film 13' is preferably stuck to the bump forming surface 9a while being heated. In this way, the occurrence of voids between the curable resin film 13 'and the bump forming surface 9a and between the curable resin film 13' and the surface 91a of the bump 91 can be further suppressed. And finally, the effect of suppressing the first protective film residue from remaining on the crown portion of the bump becomes higher.

The heating temperature of the curable resin film 13' at this time is not excessively high, and is preferably 60 to 100 ℃. Here, the "excessively high temperature" refers to a temperature at which the curable resin film 13 ' exhibits an action other than the intended action, for example, when the curable resin film 13 ' is thermosetting, resulting in thermosetting of the curable resin film 13 '.

In the sticking step, when the curable resin film 13 'is stuck to the bump forming surface 9a, the pressure applied to the curable resin film 13' (which may be referred to as "sticking pressure" in the present specification) is preferably 0.3 to 1 MPa.

In the attaching step, after the laminated structure (1)101 is formed, the laminated structure (1)101 may be used as it is in a subsequent step, or the thickness of the semiconductor wafer 9 'may be adjusted by grinding a surface (back surface) 9b of the semiconductor wafer 9' on the opposite side of the bump forming surface 9a as necessary.

The grinding of the back surface 9b of the semiconductor wafer 9' can be performed by a known method such as a method using a grinder.

When the back surface 9b of the semiconductor wafer 9 'is not ground, the thickness of the portion of the semiconductor wafer 9' from which the bumps are removed is preferably the same as the thickness of the portion of the semiconductor chip from which the bumps are removed described above.

When the back surface 9b of the semiconductor wafer 9 'is ground, the thickness of the portion of the semiconductor wafer 9' from which the bumps are removed before grinding is preferably 400 to 1200 μm, and more preferably 650 to 780 μm.

After the laminated structure (1)101 is formed by the attaching step, the first support sheet 10 is peeled from the thermosetting resin film 13' in the laminated structure (1) 101. When the back surface 9b of the semiconductor wafer 9' is ground, the first support sheet 10 is preferably peeled off after the grinding.

By performing the above-described steps, as shown in fig. 5 (b), a laminated structure (2) (i.e., a semiconductor wafer with a curable resin film) 102 having a thermosetting resin film 13 'on the bump forming surface 9a of the semiconductor wafer 9' can be obtained.

In the laminated structure (2)102, the top portions 910 of the bumps 91 of the semiconductor wafer 9 'penetrate the curable resin film 13' and protrude.

When the buffer layer 12 is energy ray-curable, it is preferable that the buffer layer 12 is cured by irradiation with an energy ray, and after the adhesiveness of the buffer layer 12 is reduced, the first support sheet 10 is peeled off from the thermosetting resin film 13'.

< first protective film Forming step >

In the manufacturing method, the first protective film forming step is performed after the attaching step, and as shown in fig. 5 (c), the first protective film 13 is formed by curing the curable resin film 13' after the attaching step.

In forming the laminated structure (1)101, the first protective film forming step may be performed after the first support sheet 10 is peeled off.

In the case of grinding the rear surface 9b of the semiconductor wafer 9', the first protective film forming step may be performed after grinding the rear surface 9 b.

By performing this step, a laminated structure (3) (i.e., a semiconductor wafer with a first protective film) 103 including the first protective film 13 on the bump forming surface 9a of the semiconductor wafer 9' can be obtained.

The curing conditions of the curable resin film 13' are not particularly limited as long as the degree of curing is such that the first protective film can sufficiently exhibit its function, and may be appropriately selected depending on the kind of the thermosetting resin film.

When the curable resin film 13 'is thermosetting, the heating temperature at the time of thermosetting the curable resin film 13' is preferably 100 to 180 ℃ and the heating time is preferably 0.5 to 5 hours. When the curable resin film 13 'is heat cured, the curable resin film 13' may be pressurized, and the pressure in this case is preferably 0.3 to 1 MPa.

When the curable resin film 13 'is curable with an energy ray, the illuminance of the energy ray when the curable resin film 13' is cured with an energy ray is preferably 180 to 280mW/cm²The light quantity of the energy ray is preferably 450 to 1500mJ/cm²。

In the laminated structure body (2) (semiconductor wafer with curable resin film) 102 shown in fig. 5 (b), if the residue from the curable resin film 13 '(curable resin film residue) does not remain on the top portions 910 of the bumps 91 of the semiconductor wafer 9', the first protective film residue does not remain on the top portions 910 after the first protective film forming step. In addition, if the amount of the residue from the curable resin film 13' (curable resin film residue) on the crown portion 910 is small, the amount of the first protective film residue on the crown portion 910 after the first protective film forming step also becomes small.

< dividing step >

In the manufacturing method, the dividing step is performed after the first protective film forming step, and as shown in fig. 5 (d), the semiconductor wafer 9' is divided to obtain the semiconductor chips 9.

Through this step, the semiconductor chip 1 with the first protective film as a target product is obtained.

The semiconductor wafer 9' can be divided by a known method.

For example, when the semiconductor wafer 9 'is divided by dicing with a dicing blade, a dicing sheet (or dicing tape) may be attached to the back surface 9b of the semiconductor wafer 9' in the laminated structure (3) (semiconductor wafer with first protective film) 103, and then dicing may be performed by a known method.

In the present specification, a structure including the first protective film on the bump formation surface of the semiconductor wafer and the dicing sheet on the back surface of the semiconductor wafer is sometimes referred to as a "stacked structure (5)". In addition, a structure in which the semiconductor wafer in the stacked structure (5) is singulated together with the first protective film to form a semiconductor chip may be referred to as a "stacked structure (6)".

When a layer in contact with an object to be bonded (for example, a semiconductor chip) is an energy ray-curable dicing sheet, the dicing sheet can be removed from the object to be bonded more easily by irradiating the layer with an energy ray after dicing to cure the layer and thereby reduce the adhesiveness.

In dicing the semiconductor wafer 9', a second protective film forming sheet may be used instead of the dicing sheet.

The second protective film forming sheet has a configuration in which a protective film forming film for forming the second protective film on the back surface of the semiconductor chip is formed on the dicing sheet. When the second protective film-forming sheet is used, the dicing sheet is removed after dicing, and finally a semiconductor chip in a state where the second protective film is attached to the back surface is obtained. That is, the semiconductor chip with the first protective film having the second protective film on the back surface of the semiconductor chip described above can be obtained by the above-described manufacturing method.

In the manufacturing method, at the stage immediately after the first protective film forming process is completed, as described above, the first protective film residue is suppressed from remaining on the crown portion 910 of the bump 91. Therefore, the first protective film residue is suppressed from remaining on the top 910 of the bump 91 of the semiconductor chip 1 with the first protective film as an object product.

In this way, in order to prevent the first protective film residue from remaining on the top portion 910 of the bump 91 immediately after the first protective film forming step is completed, as described above, it is necessary to prevent the residue (curable resin film residue) from the curable resin film 13 'from remaining on the top portion 910 of the bump 91 of the semiconductor wafer 9' at the stage where the structure body (2) (semiconductor wafer with curable resin film) 102 is laminated. Therefore, for example, as the curable resin film 13', it is sufficient to use a curable resin film whose residue is less likely to remain on the top 910 of the bump 91. In the sticking step, the top 910 of the bump 91 may be protruded from the curable resin film 13' so that the tin concentration ratio is 5% or more.

As the curable resin film 13' which is easy to obtain the effect of the present invention remarkably, the curable resin film described above can be mentioned.

That is, in the case of a thermosetting resin film, as the resin layer forming composition (III), a composition in which the weight average molecular weight of the resin component such as the polymer component (a) or the epoxy resin (B1) is in a small range, a composition in which the average particle size of the filler (D) is in a small range, a composition in which the content of the filler (D) is in a small range, or the like is preferably used. As the epoxy resin (B1), an epoxy resin which is liquid at normal temperature is preferably used.

On the other hand, when the residue from the curable resin film 13 '(curable resin film residue) cannot be suppressed from remaining on the top 910 of the bump 91 of the semiconductor wafer 9' at the stage of stacking the structural body (2) (semiconductor wafer with curable resin film) 102, it is finally necessary to perform a step of additionally preventing the first protective film residue from remaining on the top of the bump of the semiconductor chip with first protective film or reducing the remaining amount thereof. The above step is the residue reducing step.

< residue reduction step >

That is, the residue reducing step is a step of reducing the amount of residue on the bump 91 so that the ratio of the tin concentration is 5% or more after the attaching step. More specifically, the residue reducing step is performed at an arbitrary stage after the attaching step and before the semiconductor chip with the first protective film is obtained. In the residue reducing step, for example, the amount of residues such as curable resin film residues or first protective film residues remaining on the semiconductor wafer 9' or the top 910 of the bump 91 of the semiconductor chip 9 is reduced. Here, "the amount of the residue is reduced" in a state where the residue is not present, or in a state where the amount of the residue is small to the extent that the influence thereof can be ignored even if the residue is present.

In one embodiment of the manufacturing method, a residue reducing step is performed after the first protective film forming step to reduce the amount of the first protective film residue on the bump 91.

Fig. 7 is an enlarged cross-sectional view schematically illustrating an example of the residue reducing process according to the present embodiment.

In the present embodiment, after the first protective film forming step is completed, the first protective film residue 131 may remain on the crown portion 910 of the bump 91 in the laminated structure (3) (semiconductor wafer with first protective film) 103 described above. Fig. 7 (a) shows the above-described laminated structure (3), and this laminated structure (3)103 differs from the laminated structure (3)103 in fig. 5 in that the remaining amount of the first protective film residue 131 is large.

In the residue reducing step of the present embodiment, the amount of the first protective film residue 131 on the bump 91 is reduced by irradiating the upper portion of the bump 91 of the semiconductor wafer 9' in the stacked structure (3)103 with plasma. As shown in fig. 7 (b), a laminated structure in which the first protective film residue 131 is suppressed from remaining on the top portion 910 of the bump 91 is obtained in the same manner as shown in fig. 5 (c). In the present specification, a structure obtained by performing the residue reducing step on the laminated structure (3) in this manner is sometimes referred to as a laminated structure (4). In fig. 7, reference numeral 104 denotes a laminated structure (4).

The plasma irradiation condition in the residue reducing step is not particularly limited as long as the amount of the first protective film residue 131 can be sufficiently reduced.

For example in tetrafluoromethane (CF)₄) In the presence of a reactive gas such as a gas or an oxygen gas, the plasma may be irradiated for 0.5 to 5 minutes with a gas pressure of 80 to 120Pa and an applied power of 200 to 300W. However, this condition is only an example of the irradiation condition of plasma。

The irradiation range of the plasma in the residue reducing step is not particularly limited as long as the amount of the first protective film residue 131 can be sufficiently reduced, and the irradiation range may include at least the upper portion of the bump 91. In the residue reducing step, for example, the entire surface of the semiconductor wafer 9' including the first protective film 13 on the side having the bump 91 may be irradiated with plasma.

Here, although the description has been given of the case where the residue reducing step is performed after the first protective film forming step and before the dividing step, the residue reducing step of the present embodiment may be performed after the dividing step. The object to be irradiated with plasma at this time is the semiconductor chip 9 and not the semiconductor wafer 9' (in other words, the semiconductor chip 1 with the first protective film in which the first protective film residue 131 remains, not the laminated structure (3) 103). Except for this point, the residue reducing step may be performed in the same manner as described above.

Although the case where the amount of the first protective film residue 131 is reduced by the plasma irradiation is described here, other than the method of reducing the amount of the first protective film residue 131, for example, a method of causing fine particles to collide with the first protective film residue 131 may be cited.

In this case, the particles may collide with at least the upper portion of the bump 91, and the range of the particle collision may be the same as the irradiation range of the plasma.

The fine particles are not particularly limited as long as the amount of the first protective film residue 131 can be reduced, and specific examples thereof include abrasive materials formed of inorganic materials such as silica sand, alumina, and glass; dry ice particles, and the like.

Among them, the particles are preferably dry ice particles from the viewpoint that the particles can be significantly easily suppressed from remaining on the semiconductor chip with the first protective film by vaporization.

In another embodiment of the manufacturing method, a residue reducing step is performed after the attaching step to reduce the amount of curable resin film residue on the bump 91.

Fig. 8 is an enlarged cross-sectional view schematically illustrating another example of the residue reducing process in the present embodiment.

In the present embodiment, after the end of the bonding step, the curable resin film residue 131' may remain on the top 910 of the bump 91 in the laminated structure (2) (semiconductor wafer with curable resin film) 102 described above. Fig. 8 (a) shows the above-described laminated structure (2), and this laminated structure (2)102 is different from the laminated structure (2)102 in fig. 5 in that the residual amount of the curable resin film residue 131' is large.

In the residue reduction step of the present embodiment, plasma is irradiated to at least the upper portions of the bumps 91 of the semiconductor wafer 9 'in the stacked structure (2)102, thereby reducing the amount of the curable resin film residues 131' on the upper portions of the bumps 91. Thereby, as shown in fig. 8 (b), a laminated structure in which the curable resin film residue 131' is suppressed from remaining on the top 910 of the bump 91 is obtained as in fig. 5 (b). In the present specification, a structure obtained by performing the residue reducing step on the laminated structure (2) in this manner is sometimes referred to as a laminated structure (10). In fig. 8, reference numeral 110 denotes a laminated structure (10).

The irradiation conditions of plasma in the present embodiment may be the same as those described above, except that the irradiation target is different.

In the present embodiment, as in the case described above, the amount of the curable resin film residue 131 'may be reduced by using a method of colliding fine particles with the curable resin film residue 131' instead of the irradiation of plasma. In the present embodiment, the fine particles can be collided by the same method as described above.

Although the case where only the amount of the residue on the bump 91 is reduced in the residue reducing step has been described above, the residue on the bump 91 may be removed together with the portion of the bump 91 to which the residue is attached in the residue reducing step.

That is, in another embodiment of the manufacturing method, the first protective film residue on the bump 91 is removed together with the portion of the bump 91 to which the residue is attached by performing the residue reducing step after the first protective film forming step.

Fig. 9 is an enlarged cross-sectional view schematically illustrating another example of the residue reducing process in the present embodiment.

As described above, in the present embodiment, after the first protective film forming step is completed, the first protective film residue 131 remains on the crown portion 910 of the bump 91 in the laminated structure (3) (semiconductor wafer with first protective film) 103 described above. Fig. 9 (a) shows the above-described laminated structure (3), and this laminated structure (3)103 differs from the laminated structure (3)103 in fig. 5 in that the remaining amount of the first protective film residue 131 is large.

In the residue reducing step of the present embodiment, a portion of the stacked structure (3)103 where the first protective film residue 131 remains in the upper portion of the bump 91 of the semiconductor wafer 9' is removed together with the first protective film residue 131. More specifically, in the laminated structure (3)103, the bump 91 of the semiconductor wafer 9 'is cut at a lower position that is a predetermined distance from the apex of the bump 91 of the semiconductor wafer 9', and the cut piece is removed, whereby the upper portion of the bump 91 where the first protective film residue 131 remains is removed together with the first protective film residue 131. As a result, as shown in fig. 9 (b), a laminated structure (11)111 in which the bump shape was changed was obtained. Further, by using this laminated structure body (11)111 in place of the laminated structure body (3)103, the same semiconductor chip with the first protective film as the semiconductor chip with the first protective film shown in fig. 3 is finally obtained, that is, the semiconductor chip 3 with the first protective film in which the first protective film residue 131 is suppressed from remaining on the crown portion 920 of the bump 92 is obtained.

As described above, as a method of cutting the specific portion of the bump 91, a method of cutting the bump 91 using a dicing blade may be mentioned.

In this case, it is preferable that a dicing sheet is attached to the back surface 9b of the semiconductor wafer 9' in the laminated structure (3)103, and then the specific portion of the bump 91 is cut. As the dicing sheet in this case, a general dicing sheet can be used.

Except for the point that the cutting position is different, a specific portion of the bump 91 can be cut by using a dicing blade in the same manner as in the case of cutting a semiconductor wafer in general.

For example, the number of rotations of the blade is preferably 20000 to 45000rpm, and the feed speed (moving speed) is preferably 10 to 100 mm/s.

In the present specification, a structure in which the first protective film is provided on the bump formation surface of the semiconductor wafer in the laminated structure (3) and the dicing tape is provided on the back surface of the semiconductor wafer before the specific portion of the bump 91 is cut in this manner is referred to as a "laminated structure (7)".

The cutting portion of the bump 91 in the residue reducing step is not particularly limited as long as the amount of the first protective film residue 131 can be sufficiently reduced.

For example, when a bump having a height H is cut in a direction parallel to a bump formation surface of a semiconductor wafer, it is preferable that only a lower portion located at any distance of 0.15H to 0.4H from a bump apex is a cut portion of the bump, more preferably, only a lower portion located at any distance of 0.18H to 0.35H from a bump apex is a cut portion of the bump, and still more preferably, only a lower portion located at any distance of 0.21H to 0.3H from a bump apex is a cut portion of the bump.

For example, when the bump having a height H is cut in a direction not parallel to the bump formation surface of the semiconductor wafer, it is preferable that the cut portion includes a portion designated by the above numerical range.

In this embodiment, the semiconductor chip 3 with the first protective film is obtained by using the stacked structure (7) in place of the stacked structure (3)103 and then performing the same steps.

In the present embodiment, a structure in which a specific portion of a bump is cut off in the above-described manner in the stacked structure (7) may be referred to as a "stacked structure (8)", and a structure in which a semiconductor wafer in the stacked structure (8) is singulated together with a first protective film to form a semiconductor chip may be referred to as a "stacked structure (9)".

In the present embodiment, although the upper portion of the bump 91 is removed together with the first protective film residue 131, a small amount of the first protective film residue 131 may remain on the crown 920 of the bump 92 depending on the conditions at any stage before the target semiconductor chip with the first protective film is obtained. The semiconductor chip with the first protection film in the above state is the semiconductor chip 4 with the first protection film shown in fig. 4.

Here, although the description has been given of the case where the residue reducing step is performed after the first protective film forming step and before the dividing step, the residue reducing step of the present embodiment may be performed after the dividing step as described above. The object to be cut at this time is the bump 91 of the semiconductor chip 9, not the bump 91 of the semiconductor wafer 9' (in other words, the semiconductor chip 1 with the first protective film in which the first protective film residue 131 remains, not the laminated structure (3)). Except for this point, the residue reducing step can be performed in the same manner as in the above case.

However, from the viewpoint of easier cutting of the specific portion of the bump 91, the residue reducing step of the present embodiment is preferably performed after the first protective film forming step and before the dividing step.

In another embodiment of the manufacturing method, a residue reducing step is performed after the attaching step, and the residue of the curable resin film on the bump 91 is removed together with the portion of the bump 91 to which the residue is attached.

Fig. 10 is an enlarged cross-sectional view schematically illustrating another example of the residue reducing process according to the present embodiment.

As described above, in the present embodiment, after the end of the bonding step, the curable resin film residue 131' may remain on the top 910 of the bump 91 in the laminated structure (2) (semiconductor wafer with curable resin film) 102 described above. Fig. 10 (a) shows the above-described laminated structure (2), and this laminated structure (2)102 is different from the laminated structure (2)102 in fig. 5 in that the residual amount of the curable resin film residue 131' is large.

In the residue reducing step of the present embodiment, in the laminated structure (2)102, a portion where the curable resin film residue 131 ' remains on the upper portion of the bump 91 of the semiconductor wafer 9 ' is removed together with the curable resin film residue 131 '. More specifically, in the stacked structure (2)102, the bump 91 of the semiconductor wafer 9 'is cut at a lower position that is a predetermined distance from the apex of the bump 91 of the semiconductor wafer 9', and the cut piece is removed, whereby the upper portion of the bump 91 where the first protective film residue 131 'remains is removed together with the first protective film residue 131'. As a result, as shown in fig. 10 (b), a laminated structure (12)112 in which the bump shape was changed was obtained. Further, by using this laminated structure body (12)112 in place of the laminated structure body (3)103, the same semiconductor chip with the first protective film as shown in fig. 3 is finally obtained, that is, the semiconductor chip 3 with the first protective film in which the first protective film residue 131 is suppressed from remaining on the crown portion 920 of the bump 92 is obtained.

The cutting conditions of the bump 91 according to the present embodiment may be the same as those described above, except that the object to be cut is different.

As described above, the method of manufacturing the semiconductor chip with the first protection film in which the crown portion of the bump is a curved surface shown in fig. 1 and 2 and the method of manufacturing the semiconductor chip with the first protection film in which the crown portion of the bump is a flat surface shown in fig. 3 and 4 have been described.

As described above, the method for manufacturing a semiconductor chip with a first protective film having a flat top portion of a bump includes a step of removing a part of the bump of a semiconductor wafer or a semiconductor chip together with a residue attached thereto (residue reducing step). That is, the above-described method for manufacturing a semiconductor chip with a first protection film without a residue reduction step is advantageous in that a part of a bump and a part of a material for forming the first protection film are not wasted, compared to the method for manufacturing a semiconductor chip with a first protection film with a residue reduction step.

However, the method for manufacturing a semiconductor chip with a first protective film having a residue reducing step has an advantage that the amount of removal of the bump can be set to the minimum amount necessary for achieving the object, and the excess can be suppressed.

Further, the semiconductor chip with the first protection film obtained by the manufacturing method without the residue reduction step is advantageous in that the height of the bump can be easily increased as compared with the semiconductor chip with the first protection film obtained by the manufacturing method with the residue reduction step.

In addition, in the semiconductor chip with the first protection film which requires the residue reduction step in the manufacturing process, a fine void portion tends to be easily generated between the surface of the bump in the vicinity of the bump formation surface of the semiconductor chip and the first protection film. This is because, when the curable resin film residue is likely to remain on the top of the bump in the attachment step, a fine void portion tends to be generated between the surface of the bump in the vicinity of the bump formation surface and the curable resin film. In contrast, the semiconductor chip with the first protective film obtained by the manufacturing method without the residue reduction step is advantageous in that the void is less likely to be generated and the protective effect of the first protective film is higher.

Although the method for manufacturing the semiconductor chip with the first protective film shown in fig. 1 to 4 has been mainly described so far, other semiconductor chips with the first protective film may be manufactured by a manufacturing method that additionally has other steps necessary depending on the structure thereof as appropriate and at appropriate points in time in the above-described manufacturing method.

◇ evaluation method of semiconductor chip-first protective film laminate

The method for evaluating a semiconductor chip-first protective film laminate according to the present invention is a method for evaluating a semiconductor chip-first protective film laminate including a semiconductor chip and a first protective film formed on a surface of the semiconductor chip having a bump (bump forming surface), analyzing the top of the bump in the semiconductor chip-first protective film laminate by X-ray photoelectron spectroscopy (XPS) to determine the ratio of the concentration of tin to the total concentration of carbon, oxygen, silicon and tin, determining the semiconductor chip-first protective film laminate as a target semiconductor chip with a first protective film when the ratio of the tin concentration is 5% or more, when the ratio of the concentration of tin is less than 5%, the semiconductor chip-first protective film laminate is determined as a semiconductor chip with a first protective film that is not an object.

That is, the semiconductor chip-first protective film laminate may or may not be the semiconductor chip with the first protective film according to the determination result of the ratio of the concentration of tin, as in the case of the semiconductor chip with the first protective film described above, except that the ratio of the concentration of tin is not specified.

According to the method for evaluating a semiconductor chip-first protective film laminate of the present invention, it is possible to determine whether or not a semiconductor chip-first protective film laminate to be evaluated is the above-described semiconductor chip with a first protective film of the present invention. In addition, it is also possible to determine whether or not the semiconductor chip-first protective film laminate can improve the bonding strength between the bump and the substrate, and whether or not the electrical connectivity (conductivity) of the bonded body of the semiconductor chip and the substrate can be improved. In addition, it is also possible to determine whether or not the semiconductor chip-first protective film laminate can constitute a highly reliable semiconductor package in the end.

In the evaluation method, XPS analysis of the top of the head of the bump in the semiconductor chip-first protective film laminate may be performed by the same method as when XPS analysis of the top of the head of the bump in the semiconductor chip with the first protective film is performed as described previously.

The semiconductor chip-first protective film laminate before determination, which has a large concentration ratio of tin determined to be a semiconductor chip with a first protective film, has, for example, the same configuration as the semiconductor chip with a first protective film shown in fig. 1 to 4.

On the other hand, the semiconductor chip-first protective film laminate before determination, which has a small concentration ratio of tin to the extent that it cannot be determined as the semiconductor chip with the first protective film, has, for example, the same configuration as that of the semiconductor chip with the first protective film shown in fig. 2 or 4 in which the amount of the first protective film residue on the upper portion of the bump is further increased.

Examples

The present invention will be described in more detail below with reference to specific examples. However, the present invention is not limited to the examples shown below.

The following shows the ingredients used to prepare the composition for forming a thermosetting resin film.

Polymer component (A)

Polymer component (A) -1: polyvinyl butyral having structural units represented by the following formulae (i) -1, (i) -2 and (i) -3 ("S-LEC BL-10" manufactured by SEKII CHEMICAL CO., LTD., weight average molecular weight 25000, glass transition temperature 59 ℃ C.)

[ chemical formula 2]

In the formula I₁About 28, m₁Is 1 to 3, n₁Is an integer of 68-74.

Epoxy resin (B1)

Epoxy resin (B1) -1: liquid bisphenol A type epoxy resin ("EPICLON EXA-4810-1000" manufactured by DIC Corporation, weight average molecular weight 4300, epoxy equivalent 408g/eq)

Epoxy resin (B1) -2: dicyclopentadiene type epoxy resin ("EPICLON HP-7200" manufactured by DIC Corporation, molecular weight 550, epoxy equivalent 254-264 g/eq)

Heat-curing agent (B2)

Thermal curing agent (B2) -1: novolac-type phenol resin ("ショウノール (registered trademark) BRG-556" manufactured by SHOWA DENKO K.K.)

Curing Accelerator (C)

Curing accelerator (C) -1: 2-phenyl-4, 5-dihydroxymethylimidazole ("CURIZOL 2 PHZ" manufactured by SHIKOKU CHEMICALS CORPORATION)

Filling Material (D)

Filler (D) -1: epoxy-modified spherical silica ("ADMANANO YA 050C-MKK" manufactured by ADMATECHS Co., Ltd., average particle diameter of 0.05 μm)

[ example 1]

Production of first protective film Forming sheet

< preparation of composition for Forming thermosetting resin film >

The polymer component (a) -1(9.9 parts by mass), the epoxy resin (B1) -1(37.8 parts by mass), the epoxy resin (B1) -2(25.0 parts by mass), the thermosetting agent (B2) -1(18.1 parts by mass), the curing accelerator (C) -1(0.2 parts by mass), and the filler (D) -1(9.0 parts by mass) were dissolved or dispersed in methyl ethyl ketone, and stirred at 23 ℃. The amounts of the respective components to be blended are the amounts of the solid components.

< production of first protective film-forming sheet >

A release film (SP-PET 381031 manufactured by Lintec Corporation, 38 μm thick) obtained by peeling one surface of a polyethylene terephthalate film by silicone treatment was used, and the obtained composition for forming a thermosetting resin film was coated on the peeled surface and dried by heating at 120 ℃ for 2 minutes, thereby forming a thermosetting resin film having a thickness of 30 μm.

Then, the thermosetting resin film on the above-described release film was bonded to the layer to be bonded of the first support sheet using a bonding tape ("E-8510 HR" manufactured by Lintec Corporation) as the first support sheet, thereby obtaining a first protective film-forming sheet having a structure shown in fig. 6, which was formed by sequentially laminating the first support sheet, the thermosetting resin film, and the release film in the thickness direction thereof.

Production of semiconductor chip-first protective film laminate (semiconductor chip with first protective film)

The release film is removed from the first protective film forming sheet obtained as described above, and the surface (exposed surface) of the thermosetting resin film exposed thereby is pressed against the bump forming surface of the semiconductor wafer, and the first protective film forming sheet is attached to the bump forming surface of the semiconductor wafer. At this time, the first protective film-forming sheet was attached to the thermosetting resin film while heating the film using an attaching apparatus (roll laminator, "RAD-3510F/12" manufactured by Lintec Corporation) under conditions of a table temperature of 90 ℃, an attaching speed of 2 mm/sec, and an attaching pressure of 0.5 MPa. As a semiconductor wafer, a semiconductor wafer was used in which the shape of the bump was substantially spherical as shown in FIG. 1, the height of the bump was 210 μm, the width of the bump was 250 μm, the distance between adjacent bumps was 400 μm, and the thickness of the portion from which the bump was removed was 780 μm.

In this way, a laminated structure (1) is obtained in which the first protective film forming sheet is attached to the bump forming surface of the semiconductor wafer.

Then, the surface (back surface) of the semiconductor wafer on the opposite side of the bump formation surface in the obtained laminated structure (1) was ground using a grinder ("DGP 8760" manufactured by DISCO Corporation). At this time, the back surface was ground until the thickness of the semiconductor wafer where the bumps were removed was 280 μm.

Then, an ultraviolet irradiation apparatus ("RAD-2000 m/12" manufactured by Lintec Corporation) was used to irradiate at an illuminance of 230mW/cm²The light quantity was 570mJ/cm²The first protective film forming sheet in the laminated structure (1) having the ground back surface is irradiated with ultraviolet rays. Thereby, the layer in contact with the thermosetting resin film in the first support sheet in the first protective film forming sheet is subjected to ultraviolet curing.

Then, the first support sheet (attachment sheet) was peeled off from the thermosetting resin film in the laminated structure (1) using an attachment device ("RAD-2700F/12" manufactured by Lintec Corporation).

In this way, a laminated structure (2) (semiconductor wafer with a curable resin film) having a thermosetting resin film on the bump forming surface of the semiconductor wafer is obtained.

Then, the thermosetting resin film in the laminated structure (2) obtained above was thermally cured using a thermal curing apparatus ("RAD-9100 m/12" manufactured by Lintec Corporation) under conditions of a heating temperature of 130 ℃, a pressure of 0.5MPa at the time of heating, and a heating time of 2 hours, to form the first protective film.

In this way, a laminated structure (3) (semiconductor wafer with first protective film) having the first protective film on the bump formation surface of the semiconductor wafer is obtained.

Then, the upper portion of the bump of the semiconductor wafer in the laminated structure (3) obtained above was irradiated with plasma using a plasma irradiator ("RIE-10 NRT" manufactured by Samco inc., to reduce the amount of the first protective film residue on the upper portion of the bump. At this time, tetrafluoromethane (CF)₄) The plasma was irradiated for 5 minutes with a gas flow rate of 40sccm, an oxygen gas flow rate of 80sccm, an output of 250W, and a gas introduction pressure of 100 Pa. In this case, the entire surface of the semiconductor wafer including the first protective film on the side having the bumps is irradiated with plasma.

In this way, a laminated structure (4) is obtained.

Then, a dicing tape ("Adwill D-675" manufactured by linetec Corporation) was attached to the back surface (ground surface) of the semiconductor wafer in the obtained laminated structure (4), thereby obtaining a laminated structure (5) having the first protective film on the bump formation surface of the semiconductor wafer and the dicing tape on the back surface.

Then, the semiconductor wafer in the laminated structure (5) was singulated together with the first protective film (i.e., "the laminated structure (4)) using a dicing apparatus (" DFD6361 "manufactured by DISCO Corporation) and a dicing blade (" NBC-ZH2050-27HECC "manufactured by DISCO Corporation), and semiconductor chips having a size of 896 mm × 6mm were formed, thereby obtaining a laminated structure (6).

Then, an ultraviolet irradiation apparatus (Lintec) was used"RAD-2000 m/12" manufactured by Corporation) at an illuminance of 230mW/cm²The light quantity was 120mJ/cm²The dicing tape in the laminated structure (6) obtained above was irradiated with ultraviolet rays. Thereby, the layer in contact with the semiconductor chip in the dicing tape is subjected to ultraviolet curing.

Then, the semiconductor chip-first protective film laminate having the first protective film on the bump formation surface of the semiconductor chip is separated from the dicing tape after the ultraviolet irradiation and picked up.

Evaluation of bumps

< ratio of tin concentration at top of head of bump >

In the manufacturing process of the semiconductor chip-first protective film laminate, at the time point between the ultraviolet irradiation of the dicing tape in the laminated structure (6) and the picking up of the semiconductor chip-first protective film laminate, the top of the bump in the semiconductor chip-first protective film laminate was analyzed by XPS to determine the ratio of the concentration of tin to the total concentration of carbon, oxygen, silicon, and tin. Fig. 11 shows a plan view for explaining the arrangement position of the semiconductor chip-first protective film laminate as an analysis target on the dicing tape. As shown in fig. 11, 144 semiconductor chip-first protective film laminates 1' were disposed on the dicing tape 8. Wherein XPS analysis was performed on 6 semiconductor chips labeled with symbols 1 ' -1 to 1 ' -6, the first protective film laminate 1 '. The XPS analysis is performed for an upper region including a bump apex. The upper region is set as a region including the apex of the bump and identified as a circular region having a diameter of 20 μm when viewed from above downward on the bump. Then, the average value of the ratios of the tin concentrations obtained is used as the ratio of the tin concentration in the present example.

XPS analysis Using an X-ray photoelectron spectroscopy apparatus ("Quantra SXM" manufactured by ULVAC, Inc.) with an irradiation angle of 45 ° and an X-ray beam diameter of

Strip with output power of 4.5WThe process is carried out in a piece. The results are shown in the column "ratio of Sn concentration (%)" in table 1.

< shear fracture mode of bonded body of copper plate and semiconductor chip >

The picked-up semiconductor chip-first protective film laminate obtained above was placed on the surface of a flux (flux) -coated copper plate (thickness 300 μm), and heated at 260 ℃ for 2 minutes, thereby being bonded to the copper plate. At this time, the bumps in the semiconductor chip-first protective film laminate are in contact with the surface of the copper plate. Then, the copper plate was cleaned and the flux was removed.

Then, a shear force was applied to the bonded semiconductor chip-first protective film laminate in a direction parallel to the surface of the copper plate (the surface to which the semiconductor chip-first protective film laminate was bonded) using a shear force measuring device ("DAGE-serial 4000 XY" manufactured by Nordson DAGE corporation), and the bonded state was broken. Then, the fracture site was observed, and it was determined whether the fracture was "interfacial fracture at the interface between the bump and the copper plate (hereinafter, abbreviated as" interfacial fracture ") or" bump fracture (hereinafter, abbreviated as "cohesive fracture"). The results are shown in the column "shear failure mode" in Table 1.

< degree of electrical connection of bonded body of substrate and semiconductor chip >

The picked-up semiconductor chip-first protective film laminate obtained above was placed on the surface of a substrate (KIT WLP(s)300P/400P, thickness 1000 μm) coated with a flux, and heated at 350 ℃ for 2 minutes, thereby being bonded to the substrate. At this time, the bumps in the semiconductor chip-first protective film laminate are in contact with the surface of the substrate. Then, the substrate is cleaned and the flux is removed.

Then, the resistance value between the semiconductor chip and the substrate was measured using a multimeter ("3422 hicardterer" manufactured by HIOKI CORPORATION). Then, the electrical connection degree is determined as A (good) when the resistance value is 2.7-3.0 Ω, and the electrical connection degree is determined as B (bad) when the resistance value is not within the range of 2.7-3.0 Ω. The results are shown in the column "electrical connectivity" in table 1.

< TCT reliability of bonded body of substrate and semiconductor chip >

The picked-up semiconductor chip-first protective film laminate obtained above was placed on the surface of a flux-coated substrate (KIT WLP(s)300P/400P, thickness (1000) μm), and heated at 260 ℃ for 2 minutes, thereby being bonded to the substrate. At this time, the bumps in the semiconductor chip-first protective film laminate are in contact with the surface of the substrate. Then, the substrate is cleaned and the flux is removed.

The obtained joined body was stored in a TCT tester ("TSE-11A" manufactured by ESPEC CORP.), maintained at-40 ℃ for 5 minutes, heated to 125 ℃ for 5 minutes, and then cooled to-40 ℃ under temperature cycling conditions. Then, the joined body was taken out from the TCT tester every 100 times of the temperature cycle (every 100 cycles), and the electric connection degree of the taken-out joined body was evaluated by the same method as that in the above-described evaluation of "the electric connection degree of the joined body of the substrate and the semiconductor chip". Then, a Weibull (Weibull) distribution was formed based on the evaluation results, and the TCT reliability when the number of cycles was 1360 times or more at a failure rate of 63.2% was determined as a (good), and the TCT reliability when the number of cycles was less than 1360 times was determined as B (bad). The number of 1360 cycles was the number of cycles in reference example 1 described later, and this evaluation was performed based on reference example 1. In addition, the "failure" here is caused by the destruction of the bonding structure of the bump and the substrate. The results are shown in table 1 under the heading "TCT reliability".

Production of first protective film-forming sheet, production of semiconductor chip-first protective film laminate (semiconductor chip with first protective film), evaluation of bump

[ example 2]

A first protective film forming sheet was manufactured by the same method as in example 1.

Then, a semiconductor chip-first protective film laminate (semiconductor chip with first protective film) was produced by the same method as in example 1 except that the time for irradiating the upper portion of the bump of the semiconductor wafer in the laminated structure (3) with plasma was set to 3 minutes instead of 5 minutes, and the bump was evaluated. The results are shown in Table 1.

[ example 3]

Then, a semiconductor chip-first protective film laminate (semiconductor chip with first protective film) was produced by the same method as in example 1 except that the time for irradiating the upper portion of the bump of the semiconductor wafer in the laminated structure (3) with plasma was set to 1 minute instead of 5 minutes, and the bump was evaluated. The results are shown in Table 1.

[ example 4]

Production of first protective film Forming sheet

A laminated structure (3) (a semiconductor wafer with a first protective film) was produced by the same method as in example 1.

Then, a dicing tape ("Adwill D-675" manufactured by linetec Corporation) was attached to the back surface (ground surface) of the semiconductor wafer in the obtained laminated structure (3), and a laminated structure (7) having the first protective film on the bump formation surface of the semiconductor wafer and the dicing tape on the back surface was obtained.

Then, the bump was cut in a direction parallel to the bump forming surface at a lower portion only 50 μm from the bump apex under the condition of a blade revolution number of 30000rpm and a feed speed of 50mm/s using a cutting device ("DFD 6361" manufactured by DISCO Corporation) and a cutting blade ("NBC-ZH 2050-SE 27 HEEF" manufactured by DISCO Corporation, and the cut piece was removed. The same structure as in example 1 was produced except that the height of the bump was 160 μm and the crown portion was made planar by reducing the amount of the first protective film residue on the upper portion of the bump in this manner. In other words, in the present embodiment, the shape of the bump is made into the shape shown in fig. 3. The obtained laminated structure (8) is further cleaned by a cleaning unit of a dicing device.

Then, using the laminated structure (8) obtained above in place of the laminated structure (5), the semiconductor wafer in the laminated structure (8) was singulated together with the first protective film by the same method as in example 1 to form semiconductor chips having a size of 6mm × 6mm, thereby obtaining a laminated structure (9).

Then, the dicing tape in the laminated structure (9) is irradiated with ultraviolet rays using the laminated structure (9) obtained above in place of the laminated structure (6). Thereby, the layer in contact with the semiconductor chip in the dicing tape is subjected to ultraviolet curing.

Then, in the same manner as in example 1, the semiconductor chip-first protective film laminate having the first protective film on the bump formation surface of the semiconductor chip was separated from the dicing tape after the ultraviolet irradiation and picked up.

Evaluation of bumps

With respect to the semiconductor chip-first protective film laminate obtained above, bumps were evaluated by the same method as in example 1. The results are shown in Table 1.

Production of semiconductor chip and evaluation of bump

[ reference example 1]

Production of semiconductor chips

A laminated structure (1R) in which the adhesive tape was attached to the bump formation surface of the semiconductor wafer was obtained in the same manner as in example 1, except that the adhesive tape ("E-8510 HR" manufactured by Lintec Corporation) was used instead of the first protective film forming sheet from which the release film was removed.

Next, the back surface of the semiconductor wafer of the laminated structure (1R) was ground in the same manner as in example 1, except that the laminated structure (1R) obtained above was used in place of the laminated structure (1), until the thickness of the portion from which the bump was removed became 280 μm.

Then, a dicing tape ("Adwill D-675" manufactured by Lintec Corporation) was attached to the back surface (ground surface) of the semiconductor wafer, resulting in a laminated structure (2R).

Then, the adhesive tape was irradiated with ultraviolet rays in the same manner as in example 1, except that the laminated structure (2R) obtained as described above was used instead of the laminated structure (1) whose back surface was ground. In this way, the layer of the adhesive tape in contact with the bump formation surface of the semiconductor wafer is cured by ultraviolet rays.

Then, the attached sheet was peeled from the semiconductor wafer by the same method as in example 1.

In this way, a laminated structure (3R) in which the bump formation surface of the semiconductor wafer is exposed and the dicing tape is provided on the back surface of the semiconductor wafer (i.e., a dicing tape-attached semiconductor wafer) is obtained.

Next, a semiconductor wafer in the stacked structure (3R) was singulated by the same method as in example 1, except that the stacked structure (3R) obtained above was used in place of the stacked structure (5), and semiconductor chips having a size of 6mm × 6mm were formed, thereby obtaining a stacked structure (4R).

Then, the dicing tape in the laminated structure (4R) was irradiated with ultraviolet rays in the same manner as in example 1, except that the laminated structure (4R) obtained above was used in place of the laminated structure (6). Thereby, the layer in contact with the semiconductor chip in the dicing tape is subjected to ultraviolet curing.

Then, the semiconductor chip is separated and picked up from the ultraviolet-irradiated dicing tape.

Evaluation of bumps

With respect to the semiconductor chip obtained above, bumps were evaluated by the same method as in example 1. The results are shown in Table 1.

Comparative example 1

Next, a semiconductor chip-first protective film laminate was produced by the same method as in example 1, except that the upper portion of the bump of the semiconductor wafer in the laminated structure (3) was not irradiated with plasma, and the bump was evaluated. The results are shown in Table 1.

Comparative example 2

Next, a semiconductor chip-first protective film laminate was produced by the same method as in example 1 except that the time for irradiating the upper portion of the bump of the semiconductor wafer in the laminated structure (3) with plasma was set to 0.1 minute instead of 5 minutes, and the bump was evaluated. The results are shown in Table 1.

[ Table 1]

As is apparent from the above results, in the semiconductor chip-first protective film laminates according to examples 1 to 4, the ratio of the concentration of tin was 6.5% or more (6.5 to 13.3%), and the amount of the first protective film residue on the top of the head of the bump was small. This is because, in the case of manufacturing the semiconductor chip-first protective film laminate, the residue reducing step is performed by irradiating the upper portion of the bump of the semiconductor wafer with plasma for 5 to 1 minute in examples 1 to 3, and the residue reducing step is performed by removing the upper portion of the bump in example 4.

In these examples, the bonding strength between the copper plate and the bump was high, and the shear failure of the bonded body of the copper plate and the semiconductor chip was cohesive failure (failure of the bump). In addition, the electrical connection degree of the joined body of the substrate and the semiconductor chip is also high. And the TCT reliability of the joined body of the board and the semiconductor chip is also high.

From the above results, it was confirmed that the semiconductor chip with the first protective film, which is the target semiconductor chip-first protective film laminate manufactured in examples 1 to 4, is the semiconductor chip with the first protective film.

It was confirmed that the semiconductor chips with the first protective films (semiconductor chips — first protective film laminates) of examples 1 to 4 suppressed the first protective film residue from remaining on the tops of the bumps, and thus a highly reliable semiconductor package could be constructed.

In the semiconductor wafer and the semiconductor chip of reference example 1, the first protective film is not provided, and there is no factor that decreases the ratio of the tin concentration, and actually, the ratio of the tin concentration is a high level.

The above evaluation results in examples 1 to 4, particularly in examples 1,2 and 4 have a level similar to the evaluation result in reference example 1, and it is judged that the effect of reducing the amount of the first protective film residue on the top of the head of the bump is high in examples 1 to 4.

In contrast, in the semiconductor chip-first protective film laminate of comparative example 1, since the residue reducing step was not performed, the ratio of the concentration of tin was very low as compared with examples 1 to 4, and tin was not substantially detected.

In this comparative example, reflecting the above results, the bonding strength between the copper plate and the bump was low, and the shear failure of the bonded body of the copper plate and the semiconductor chip was interfacial failure (interfacial failure between the bump and the copper plate). In addition, the electrical connectivity of the joined body of the substrate and the semiconductor chip is also low. When the reliability of TCT of the bonded body of the substrate and the semiconductor chip was evaluated, the bonded structure of the bump and the substrate was broken at a stage before the 1-cycle temperature cycle was completed.

In the semiconductor chip-first protective film laminate of comparative example 2, the ratio of the concentration of tin was 3.4%, and the amount of first protective film residue on the top of the head of the bump was large. This is because, in the case of manufacturing the semiconductor chip-first protective film laminate, the time for irradiating the upper portion of the bump of the semiconductor wafer with plasma is short, and the amount of the first protective film residue on the upper portion of the bump is not sufficiently reduced.

In this comparative example, reflecting the above results, the bonding strength between the copper plate and the bump was high, but the electrical connectivity of the bonded body of the substrate and the semiconductor chip was low. Further, the TCT reliability of the bonded body of the substrate and the semiconductor chip is also low.

From the above results, it was confirmed that the semiconductor chip-first protective film laminate manufactured in comparative examples 1 to 2 was not the intended semiconductor chip with the first protective film.

It was confirmed that the semiconductor chip-first protective film laminate of comparative examples 1 to 2 could not constitute a highly reliable semiconductor package because the first protective film residue was not suppressed from remaining on the tops of the bumps.

Industrial applicability

The present invention can be used for manufacturing a semiconductor chip or the like having bumps at connection pad portions, which is used in flip chip mounting.

Description of the reference numerals

1. 2, 3, 4: a semiconductor chip with a first protective film (semiconductor chip-first protective film laminate); 1': a semiconductor chip-first protective film laminate; 9: a semiconductor chip; 9': a semiconductor wafer; 9 a: a bump formation surface of a semiconductor chip (semiconductor wafer); 91. 92: bumps of a semiconductor chip (semiconductor wafer); 91a, 92 a: the surface of the bump; 910. 920: the top of the head of the bump; 13: a first protective film; 131: a first protective film residue; 13': a curable resin film; 131': a curable resin film residue.

Claims

1. A semiconductor chip with a first protective film includes a semiconductor chip and a first protective film formed on a surface of the semiconductor chip having a bump,

when the top of the head of the bump is analyzed by X-ray photoelectron spectroscopy, the ratio of the concentration of tin to the total concentration of carbon, oxygen, silicon, and tin is 5% or more.

2. A method for manufacturing a semiconductor chip with a first protective film according to claim 1, comprising:

a step of attaching a curable resin film to the surface of the semiconductor wafer having the bumps;

forming a first protective film by curing the cured resin film after the application; and

obtaining semiconductor chips by dividing the semiconductor wafer,

in the step of attaching the curable resin film, the top of the bump is made to protrude from the curable resin film so that the tin concentration ratio is 5% or more, or

The step of attaching the curable resin film further includes a step of reducing the amount of residue on the bump so that the ratio of the tin concentration is 5% or more.

3. A method for evaluating a semiconductor chip-first protective film laminate, which comprises a semiconductor chip and a first protective film formed on a surface of the semiconductor chip having a bump,

the semiconductor chip-first protective film laminate is determined as a target semiconductor chip with a first protective film when the ratio of the tin concentration is 5% or more, and as a non-target semiconductor chip with a first protective film when the ratio of the tin concentration is less than 5%.