CN114517065A

CN114517065A - Dicing adhesive film with spacer

Info

Publication number: CN114517065A
Application number: CN202111339140.8A
Authority: CN
Inventors: 吉田直子; 木村雄大; 高本尚英; 杉村敏正; 中浦宏
Original assignee: Nitto Denko Corp
Current assignee: Nitto Denko Corp
Priority date: 2020-11-20
Filing date: 2021-11-12
Publication date: 2022-05-20
Also published as: JP2022082237A; TW202226386A; KR20220069820A

Abstract

The invention provides a dicing adhesive film with a spacer, comprising: a laminate sheet having an adhesive layer for adhering to an adherend and a spacer layer superposed on the adhesive layer; and a dicing tape which is overlapped with the adhesive layer of the laminated sheet and holds the laminated sheet, wherein the bending rigidity of the laminated sheet at room temperature is 0.05 N.mm²The above.

Description

Dicing adhesive film with spacer

Technical Field

The present invention relates to a dicing adhesive film with spacers used in, for example, manufacturing a semiconductor integrated circuit.

Background

A method of manufacturing a semiconductor integrated circuit generally includes: the method includes a pre-process of forming a circuit surface on one surface of a wafer by a highly integrated electronic circuit, and a post-process of cutting out chips from the wafer on which the circuit surface is formed and assembling the chips.

With the recent further development of integration technology, a semiconductor integrated circuit is sometimes assembled by stacking NAND-type memory chips several times in a post-process. In this case, for example, a semiconductor integrated circuit having a structure in which a plurality of NAND chips for storage are stacked on a controller chip for control is manufactured. In the semiconductor integrated circuit having such a configuration, for example, a spacer layer is disposed between a controller chip for control and a NAND chip for memory which is located closest to the controller chip.

Conventionally, a thin film for processing used in the manufacture of the above-described semiconductor integrated circuit is known. Such a processing film is used in the post-process for each purpose, and various types are available depending on the purpose.

As a processing film, for example, a dicing die bonding film for attaching a semiconductor chip to an adherend is known. The dicing die-bonding film includes: the dicing tape includes a base material layer and a pressure-sensitive adhesive layer, and a chip bonding layer laminated on the pressure-sensitive adhesive layer of the dicing tape and used for bonding an adherend.

On the other hand, as a film for processing, there is known a dicing adhesive film with a spacer, which has, for bonding the spacer layer to an adherend: the adhesive sheet includes a blank layer, an adhesive layer for adhering the blank layer to an adherend, and a dicing tape superposed on the adhesive layer.

For example, in a subsequent step in the manufacture of a semiconductor integrated circuit, first, a step 1 is performed in which a dicing die bonding film having a dicing tape and a die bonding layer is used as a processing film, and a controller chip w 'for control, which is formed into a small chip, is fixed to the surface of an adherend (a wiring substrate Z or the like) via the die bonding layer d' by using the dicing die bonding film, as shown in fig. 1A. Next, step 2 is performed in which a dicing adhesive film having a dicing tape, an adhesive layer, and a spacer layer with a spacer is used as a processing film, and the diced spacer layer is fixed to the surface of an adherend (wiring substrate) via the adhesive layer using this film as shown in fig. 1B. Next, a 3 rd step is performed in which the dicing die bonding film as described above is used as the processing film, and as shown in fig. 1C, the memory NAND chips w "formed into a small piece are fixed to the spacer layer 10 via the die bonding layer d" by using the dicing die bonding film, and the memory NAND chips w "are further stacked in the same manner.

The semiconductor integrated circuit described above is manufactured through these steps.

In step 2, for example, a dicing adhesive film with spacers including a spacer layer formed of a thin silicon wafer is used, and the following steps are performed: a step of forming grooves in the blank layer and the adhesive layer by cutting with a blade or the like and cutting the grooves into small pieces; a step of peeling the dicing blank layer to which the adhesive layer is adhered from the dicing tape; and a step of bonding the spacer layer in a state where the adhesive layer is adhered to an adherend (wiring board).

In such a method for manufacturing a semiconductor integrated circuit, a dicing adhesive film with spacers used in the 2 nd step is known to include a spacer layer formed of a metal foil instead of a spacer layer formed of a silicon wafer (for example, patent document 1).

Specifically, the spacer layer in the dicing adhesive film with spacers described in patent document 1 is a metal foil such as a rolled steel foil or a stainless steel foil.

According to the dicing adhesive film with spacers described in patent document 1, since the spacer layer is not a silicon wafer but a metal foil, stable manufacturing supply can be maintained without being affected by a shortage of the supply amount of the silicon wafer. In addition, since the back grinding step for reducing the thickness of the silicon wafer as described above is not required, the manufacturing process of the semiconductor integrated circuit can be simplified.

However, in order to secure electrical insulation between the memory NAND chip stacked on the spacer layer and the wiring board by the spacer layer, a material having electrical insulation such as resin is more suitable as a material constituting the spacer layer than a conductive metal.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2007-220913

Disclosure of Invention

Problems to be solved by the invention

Therefore, it is conceivable to form a spacer layer from an electrically insulating resin or the like and use a dicing adhesive film with spacers, which is a laminated sheet in which the spacer layer and the adhesive layer are laminated, in the step 2.

However, when a simple laminated sheet having an electrically insulating spacer layer and an adhesive layer is diced on a dicing tape and peeled from the dicing tape in the above-described 2 nd step, the diced laminated sheet may not be picked up due to a peeling failure or the like.

In order to prevent such a problem, a dicing adhesive film with a spacer is desired which has good pickup properties when the above laminated sheet obtained by dicing is peeled from a dicing tape.

However, it is not necessarily said that sufficient studies have been made on a dicing adhesive film with a spacer, which has good pickup properties when a laminated sheet of an inner layer and an adhesive layer is peeled from a dicing tape.

Accordingly, an object of the present invention is to provide a dicing adhesive film with a spacer having good pickup properties when a laminated sheet of a blank layer and an adhesive layer is peeled from a dicing tape.

Means for solving the problems

In order to solve the above problems, a dicing adhesive film with spacers according to the present invention includes:

a laminate sheet having an adhesive layer for adhering to an adherend and a spacer layer superposed on one surface of the adhesive layer; and

a dicing tape which is stacked on the other surface of the adhesive layer of the laminate sheet and holds the laminate sheet, wherein the laminate sheet has a bending rigidity of 0.05N · mm at room temperature²The above.

According to the dicing adhesive film with spacers of the above aspect, the pickup property when peeling the laminated sheet of the blank layer and the adhesive layer from the dicing tape becomes good.

In the dicing adhesive film with a spacer, the laminate sheet preferably has an elastic modulus of 1GPa or more. This further improves the pickup property when the laminated sheet of the blank layer and the adhesive layer is peeled from the dicing tape.

In the dicing adhesive film with a spacer, the peeling force between the adhesive layer and the blank layer may be 0.1N/20mm or more.

The thickness of the spacer layer of the dicing adhesive film with spacers may be 3 μm or more and 300 μm or less.

The thickness of the adhesive layer of the dicing adhesive film with spacers may be 10 μm or more and 200 μm or less.

This further improves the pickup property when the laminated sheet of the blank layer and the adhesive layer is peeled from the dicing tape.

In the dicing and bonding film with spacer, the material of the spacer layer is preferably at least 1 selected from the group consisting of polyimide, polyamideimide, polyester, polybenzimidazole, polyetherimide, polyphenylene sulfide and polyether ether ketone. This further improves the pickup property when the laminated sheet of the blank layer and the adhesive layer is peeled from the dicing tape.

The dicing adhesive film with spacers can be used for embedding a semiconductor chip in the case of manufacturing a chip-embedded semiconductor integrated circuit or for securing a space for stacking a memory semiconductor chip on a control semiconductor chip in the case of manufacturing a buried-wire type semiconductor integrated circuit.

Drawings

Fig. 1A is a schematic cross-sectional view showing an intermediate process of one example of a manufacturing process of a semiconductor integrated circuit.

Fig. 1B is a schematic cross-sectional view showing an intermediate process of one example of a manufacturing process of a semiconductor integrated circuit.

Fig. 1C is a schematic cross-sectional view showing an intermediate process of an example of a manufacturing process of a semiconductor integrated circuit.

Fig. 2 is a schematic perspective view of the dicing adhesive film with spacers according to the present embodiment.

Fig. 3 is a cross-sectional view of the dicing adhesive film with spacers of the present embodiment cut in the thickness direction.

Fig. 4A is a cross-sectional view schematically showing a case (mounting) where a dicing adhesive film with spacers is used in a manufacturing method of a semiconductor integrated circuit.

Fig. 4B is a cross-sectional view schematically showing a case where a dicing adhesive film with spacers is used in the manufacturing method of a semiconductor integrated circuit (blade dicing).

Fig. 4C is a cross-sectional view schematically showing a case where a dicing adhesive film with spacers is used (after dicing with a blade) in a manufacturing method of a semiconductor integrated circuit.

Fig. 4D is a cross-sectional view schematically showing a case (pickup) where a dicing adhesive film with spacers is used in a manufacturing method of a semiconductor integrated circuit.

Fig. 5A is a cross-sectional view schematically showing another example of the semiconductor integrated circuit.

Fig. 5B is a cross-sectional view schematically showing another example of the semiconductor integrated circuit.

Fig. 5C is a cross-sectional view schematically showing another example of the semiconductor integrated circuit.

Fig. 5D is a cross-sectional view schematically showing another example of the semiconductor integrated circuit.

Fig. 5E is a cross-sectional view schematically showing another example of the semiconductor integrated circuit.

Fig. 6A is a schematic cross-sectional view schematically showing a case where a laminated sheet having a blank layer and an adhesive layer is produced.

Fig. 6B is a schematic cross-sectional view schematically showing a case where a laminated sheet having a blank layer and an adhesive layer is produced.

Fig. 7A is a schematic cross-sectional view schematically showing a state in the middle of the process of manufacturing the spacer-attached cut adhesive film of the present embodiment.

Fig. 7B is a schematic cross-sectional view schematically showing a cross section of the dicing adhesive film with spacers in the manufacturing process cut in the longitudinal direction.

Fig. 8A is a schematic cross-sectional view schematically showing a case in the middle of manufacturing the dicing adhesive film with spacers of the present embodiment.

Fig. 8B is a schematic cross-sectional view schematically showing a section in which a dicing adhesive film with spacers in the manufacturing process is cut in the longitudinal direction.

Fig. 8C is a schematic cross-sectional view schematically showing a cross section of the dicing adhesive film with spacers in the manufacturing process cut in the longitudinal direction.

Fig. 8D is a schematic cross-sectional view schematically showing a cross section of the dicing adhesive film with spacers in the manufacturing process cut in the longitudinal direction.

Fig. 9A is a schematic cross-sectional view schematically showing a case in the middle of manufacturing the dicing adhesive film with spacers of the present embodiment.

Fig. 9B is a schematic cross-sectional view schematically showing a cross section of the dicing adhesive film with spacers in the manufacturing process cut in the longitudinal direction.

Fig. 9C is a schematic cross-sectional view schematically showing a cross section of the dicing adhesive film with spacers in the manufacturing process cut in the longitudinal direction.

Fig. 9D is a schematic cross-sectional view schematically showing a cross section of the dicing adhesive film with spacers in the manufacturing process cut in the longitudinal direction.

Fig. 10A is a schematic cross-sectional view schematically showing another example of the dicing adhesive film with spacers according to the present embodiment.

Fig. 10B is a schematic cross-sectional view schematically showing another example of the dicing adhesive film with spacers in the manufacturing process.

Description of the reference numerals

1: a cut adhesive film with a spacer,

10: the spacing layer is provided with a plurality of spacers,

20: an adhesive layer is arranged on the surface of the substrate,

30: the cutting of the tape is carried out,

31: substrate layer, 32: a layer of an adhesive agent, wherein the adhesive agent,

l: bonding wire, Z: a substrate, a first electrode and a second electrode,

d', d ": chip bonding layer, w', w ": a semiconductor chip having a plurality of semiconductor chips,

h: peeling tape, T: a transfer belt is provided.

Detailed Description

Hereinafter, embodiments of the dicing adhesive film with spacers according to the present invention will be described with reference to the drawings.

The dicing adhesive film 1 with spacers of the present embodiment is a long sheet as shown in fig. 2, and is stored in a rolled state until use. Fig. 3 shows a cross-sectional view taken along the thickness direction along the line III-III in fig. 2.

As shown in fig. 3, the dicing adhesive film 1 with spacers according to the present embodiment includes: a laminate sheet having an adhesive layer 20 for adhering to an adherend and a blank layer 10 superposed on one surface of the adhesive layer 20; and

and a dicing tape 30 that overlaps and holds the laminate sheet on the other surface of the adhesive layer 20 of the laminate sheet. The adhesive layer 20 is to be adhered to an adherend such as a circuit board or a semiconductor chip in the manufacture of a semiconductor integrated circuit.

As shown in fig. 2 and 3, when the dicing adhesive film 1 with a spacer is viewed from one side in the thickness direction, the dicing tape 30 is in a band shape, and the blank layer 10 and the adhesive layer 20 are circular and arranged in the longitudinal direction of the dicing tape 30.

The dicing adhesive film 1 with spacers according to the present embodiment can be used by bonding the adhesive layer 20 to the substrate Z so that the controller chip w' for control is embedded in the adhesive layer 20. The dicing adhesive film 1 with spacers according to the present embodiment can be used to bond the NAND-type memory chip w ″ to the bank layer 10 bonded to the substrate Z via the adhesive layer 20.

As shown in fig. 3, the dicing adhesive film 1 with a spacer according to the present embodiment may further include a protective film (release tape H) for protecting the surface of the blank layer 10 and a part of the surface of the pressure-sensitive adhesive layer 32 of the dicing tape 30.

< spacer layer of dicing adhesive film with spacer >

The thickness (average thickness) of the spacer layer 10 may be 3 μm or more and 300 μm or less, or 3 μm or more and 100 μm or less.

The thickness of the spacer layer 10 is calculated by averaging the measured values of the thickness at least 5 randomly selected positions. In the case where the spacer layer 10 is a laminate, the thickness of the spacer layer 10 is the thickness of the laminate (total thickness of the spacer layer 10).

The spacer layer 10 is typically made of resin. The spacer layer 10 typically contains at least 50 mass% resin. The material of the spacer layer 10 is preferably at least 1 selected from the group consisting of polyimide, polyamideimide, polyester, polybenzimidazole, polyetherimide, polyphenylene sulfide, and polyether ether ketone, more preferably at least one of polyimide and polyetherimide, and still more preferably polyimide.

In other words, the spacer layer 10 is preferably made of polyimide, polyamideimide, polyester (polyethylene terephthalate, etc.), polybenzimidazole, polyetherimide, polyphenylene sulfide, polyether ether ketone, or the like.

By making the spacer layer 10 of the above-described material, there is an advantage that the spacer layer 10 can have sufficient electrical insulation. In addition, when a reflow soldering process is performed in the manufacture of a semiconductor integrated circuit, the spacer layer 10 can have heat resistance against a high temperature of, for example, about 260 ℃.

< adhesive layer of dicing adhesive film with spacer >

The thickness (average thickness) of the adhesive layer 20 is not particularly limited, and is, for example, 1 μm or more and 200 μm or less. The thickness is preferably 10 μm or more and 200 μm or less, and more preferably 20 μm or more and 150 μm or less. When the adhesive layer 20 is a laminate, the thickness of the adhesive layer 20 is the thickness of the laminate (the total thickness of the adhesive layer 20).

The thickness of the adhesive layer 20 is calculated by averaging the measured values of the thickness at least at 10 randomly selected positions.

When the thickness of the adhesive layer 20 is, for example, 100 μm or more, it is preferably used for the FOD application (application for embedding a semiconductor chip in the manufacture of a chip-embedded semiconductor integrated circuit) described later.

When the thickness of the adhesive layer 20 is small, for example, less than 100 μm, the adhesive layer is suitably used for the later-described FOW application (application for securing a space for stacking a memory semiconductor chip on a control semiconductor chip in manufacturing a buried-wire-type semiconductor integrated circuit).

The adhesive layer 20 may have a single-layer structure, as shown in fig. 3, for example. In the present specification, a single layer means a layer having only the same composition. The single layer also includes a plurality of layers formed of the same composition.

On the other hand, the adhesive layer 20 may have a multilayer structure in which layers of 2 or more different compositions are stacked, for example.

The adhesive layer 20 may include at least one of a thermosetting resin and a thermoplastic resin. The adhesive layer 20 preferably contains a thermosetting resin and a thermoplastic resin.

Examples of the thermosetting resin include: epoxy resins, phenolic resins, amino resins, unsaturated polyester resins, polyurethane resins, silicone resins, thermosetting polyimide resins, and the like. As the thermosetting resin, can use only 1 or more than 2. The thermosetting resin is preferably an epoxy resin in terms of containing less ionic impurities and the like which may cause corrosion of the semiconductor chip to be die-bonded. As the curing agent for the epoxy resin, a phenol resin is preferable.

Examples of the epoxy resin include: bisphenol A type, bisphenol F type, bisphenol S type, brominated bisphenol A type, hydrogenated bisphenol A type, bisphenol AF type, biphenyl type, naphthalene type, fluorene type, phenol novolac type, o-cresol novolac type, trihydroxyphenyl methane type, tetraphenyl hydroxy ethane type, hydantoin type, triglycidyl isocyanurate type, or glycidyl amine type.

The phenolic resin can function as a curing agent for the epoxy resin. Examples of the phenolic resin include: and a novolak-type phenol resin, a resol-type phenol resin, and a polyoxyethylene such as a poly-p-oxystyrene.

Examples of the novolak phenol resin include: phenol novolac resins, phenol aralkyl resins, cresol novolac resins, tert-butylphenol novolac resins, nonylphenol novolac resins, and the like.

The phenolic resin may be used alone or in combination of 1 or more.

In the adhesive layer 20, the hydroxyl group of the phenol resin is preferably 0.5 equivalent or more and 2.0 equivalents or less, and more preferably 0.7 equivalent or more and 1.5 equivalents or less, relative to 1 equivalent of the epoxy group of the epoxy resin. This enables the curing reaction of the epoxy resin and the phenol resin to sufficiently proceed.

In the case where the adhesive layer 20 contains a thermosetting resin, the content ratio of the thermosetting resin in the adhesive layer 20 is preferably 5% by mass or more and 60% by mass or less, and more preferably 10% by mass or more and 50% by mass or less, with respect to the total mass of the adhesive layer 20. This enables the adhesive layer 20 to appropriately exhibit a function as a thermosetting adhesive.

Examples of the thermoplastic resin that can be contained in the adhesive layer 20 include: examples of the thermoplastic resin include natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, an ethylene-vinyl acetate copolymer, an ethylene-acrylic acid ester copolymer, a polybutadiene resin, a polycarbonate resin, a thermoplastic polyimide resin, a 6-polyamide resin, a polyamide resin such as a 6, 6-polyamide resin, a phenoxy resin, an acrylic resin, a saturated polyester resin such as PET or PBT, a polyamideimide resin, and a fluororesin.

As the thermoplastic resin, an acrylic resin is preferable in that the adhesiveness of the adhesive layer 20 can be further ensured because ionic impurities are less and the heat resistance is high.

The thermoplastic resin may be used alone in 1 kind or in 2 or more kinds.

The acrylic resin is preferably a polymer having the largest number of alkyl (meth) acrylate constituent units in the molecule in terms of mass ratio. Examples of the alkyl (meth) acrylate include C2 to C4 alkyl (meth) acrylates having 2 to 4 carbon atoms in the alkyl moiety (usually a saturated hydrocarbon).

The acrylic resin may contain a constituent unit derived from another monomer component copolymerizable with the alkyl (meth) acrylate monomer.

Examples of the other monomer components include: carboxyl group-containing monomers, acid anhydride monomers, hydroxyl group-containing (hydroxyl group-containing) monomers, glycidyl group-containing monomers, sulfonic acid group-containing monomers, phosphoric acid group-containing monomers, functional group-containing monomers such as acrylamide and acrylonitrile, and other various polyfunctional monomers.

The acrylic resin is preferably a copolymer of an alkyl (meth) acrylate (particularly, an alkyl (meth) acrylate having an alkyl moiety of 4 or less carbon atoms), a carboxyl group-containing monomer, a nitrogen atom-containing monomer, and a polyfunctional monomer (particularly, a polyglycidyl-based polyfunctional monomer), and more preferably a copolymer of ethyl acrylate, butyl acrylate, acrylic acid, acrylonitrile, and polyglycidyl (meth) acrylate, in order to exhibit higher cohesive force in the adhesive layer 20.

When the adhesive layer 20 contains a thermosetting resin and a thermoplastic resin, the content ratio of the thermoplastic resin in the adhesive layer 20 is preferably 5 mass% or more and 50 mass% or less, more preferably 10 mass% or more and 45 mass% or less, and still more preferably 20 mass% or more and 40 mass% or less, with respect to the total mass of organic components other than the filler (for example, the thermosetting resin, the thermoplastic resin, the curing catalyst, and the like, the silane coupling agent, and the dye). The elasticity and viscosity of the adhesive layer 20 can be adjusted by changing the content ratio of the thermosetting resin.

When the thermoplastic resin of the adhesive layer 20 has a thermosetting functional group, an acrylic resin containing a thermosetting functional group can be used as the thermoplastic resin, for example. The thermosetting functional group-containing acrylic resin preferably contains a constituent unit derived from an alkyl (meth) acrylate in the largest mass ratio in the molecule. Examples of the alkyl (meth) acrylate include the alkyl (meth) acrylates exemplified above.

On the other hand, examples of the thermosetting functional group in the thermosetting functional group-containing acrylic resin include: glycidyl groups, carboxyl groups, hydroxyl (hydroxyl) groups, isocyanate groups, and the like.

The adhesive layer 20 preferably contains an acrylic resin containing a thermosetting functional group and a curing agent. Examples of the curing agent include those exemplified as the curing agent that can be contained in the pressure-sensitive adhesive layer 32 (isocyanate compounds and the like). When the thermosetting functional group in the thermosetting functional group-containing acrylic resin is a glycidyl group, a compound having a plurality of phenol structures in the molecule is preferably used as the curing agent. For example, the above-mentioned various phenolic resins can be used as the curing agent.

The adhesive layer 20 preferably contains a filler. By changing the amount of the filler in the adhesive layer 20, the elasticity and viscosity of the adhesive layer 20 can be more easily adjusted. Further, physical properties such as electrical conductivity, thermal conductivity, and elastic modulus of the adhesive layer 20 can be adjusted.

Examples of the filler include inorganic fillers and organic fillers. As the filler, an inorganic filler is preferable.

Examples of the inorganic filler include fillers containing silica such as aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, alumina, aluminum nitride, boron nitride, crystalline silica, and amorphous silica. Further, examples of the material of the inorganic filler include: simple metal substances such as aluminum, gold, silver, copper and nickel, alloys and the like. Can be aluminum borate whisker, amorphous carbon black, graphite and other fillers. The shape of the filler may be various shapes such as spherical, needle-like, and flake-like. As the filler, can use only the above-mentioned 1 or more than 2.

When the adhesive layer 20 contains a filler, the content ratio of the filler is preferably 30 mass% or more and 70 mass% or less, more preferably 40 mass% or more and 60 mass% or less, and still more preferably 40 mass% or more and 55 mass% or less, with respect to the total mass of the adhesive layer 20.

The adhesive layer 20 may contain other components as necessary. Examples of the other components include: curing catalysts, flame retardants, silane coupling agents, ion scavengers, dyes, and the like.

Examples of the flame retardant include: antimony trioxide, antimony pentoxide, brominated epoxy resins, and the like.

Examples of the silane coupling agent include: beta- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane, gamma-glycidoxypropyltrimethoxysilane, gamma-glycidoxypropylmethyldiethoxysilane, etc.

Examples of the ion scavenger include: hydrotalcites, bismuth hydroxide, benzotriazole, and the like.

As the other additives, only 1 kind or 2 or more kinds can be used.

The adhesive layer 20 preferably contains a thermoplastic resin (particularly, an acrylic resin), a thermosetting resin, and a filler, in order to easily adjust elasticity and viscosity.

The content ratio of the thermoplastic resin and the thermosetting resin is preferably 20 mass% or more and 95 mass% or less, more preferably 30 mass% or more and 90 mass% or less, and further preferably 40 mass% or more and 85 mass% or less with respect to the total mass of the adhesive layer 20.

When the dicing adhesive film 1 with spacers of the present embodiment is used, the adhesive layer 20 can be cured by heat treatment or the like. For example, the adhesive layer 20 with the spacer layer 10 may be bonded to the substrate Z so that the controller chip w' for control on the substrate Z is covered with the adhesive layer 20, and then heat treatment (for example, curing at 70 ℃ or higher and 150 ℃ or lower) is performed to cure the adhesive layer 20.

< laminate sheet (blank layer and adhesive layer) in dicing adhesive film with spacer >

The bending rigidity of the laminated sheet in which the blank layer 10 and the adhesive layer 20 were laminated at room temperature was 0.05 N.mm²The above. The bending rigidity is more preferably 0.10 N.mm²Above, more preferably 0.50 N.mm²Above, 2.0 N.mm is particularly preferable²The above.

Since the flexural rigidity is 0.05 N.mm²As described above, for example, as shown in fig. 4D, when the laminated sheet is pushed up via the dicing tape 30, the laminated sheet is easily peeled off from the dicing tape 30. More specifically, the bending rigidity is 0.05N · mm²This is the aboveA high value can suppress the laminate from deforming following the deformation of the dicing tape 30 when the laminate is lifted as described above. Since the deformation of the laminated sheet is suppressed, the force at the time of jacking up the laminated sheet is easily converted into a force for peeling. Therefore, the pickup performance becomes good.

The bending rigidity may be 25.0N · mm²Hereinafter, the thickness may be 20.0N · mm²The following.

The room temperature is, for example, 20 ℃ to 25 ℃, and 25 ℃ can be adopted as the room temperature.

The bending stiffness is calculated by the following formula (1). In the formula (1), b represents the length in the longitudinal direction (the length of one side in the case of a square) of the rectangular spacer layer 10 (the size when the spacer layer is used as a small piece by dicing), F represents the tensile modulus, h represents the thickness of the laminated sheet, and λ represents the distance from the upper edge of the laminated sheet to the neutral axis. In the formula (1), the calculation of the bending stiffness was performed with the laminate regarded as a single layer. Specifically, the bending stiffness is measured by the method described in the examples below.

The tensile modulus in formula (1) is measured by the method described later.

Note) consider the laminate as a single layer to calculate λ

As can be understood from equation (1), the bending rigidity can be increased by further increasing the elastic modulus of at least one of the blank layer 10 and the adhesive layer 20 and by further increasing the thickness of at least one of the blank layer 10 and the adhesive layer 20. On the other hand, the bending rigidity can be reduced by further reducing the elastic modulus of at least one of the blank layer 10 and the adhesive layer 20 and by further reducing the thickness of at least one of the blank layer 10 and the adhesive layer 20.

The elastic modulus (tensile modulus) of the laminate sheet is preferably 1GPa or more, more preferably 1.5GPa or more, and still more preferably 2GPa or more. This can provide a better pickup property when the laminated sheet of the blank layer and the adhesive layer is peeled from the dicing tape 30.

The tensile modulus of the laminate sheet may be 5GPa or less, or may be 4GPa or less.

The tensile modulus was measured as follows. A sample for measurement having a length of 40mm and a width of 10mm was cut out from a laminated sheet in which the blank layer 10 and the adhesive layer 20 were laminated, and the tensile storage modulus from-30 ℃ to 300 ℃ was measured using a solid viscoelasticity measuring apparatus. The measurement conditions are that the frequency is 1Hz, the temperature rising speed is 10 ℃/min, and the chuck interval is 20.0 mm. Then, the measured value of the storage modulus at room temperature (preferably 25 ℃) is used as the tensile modulus.

The tensile modulus can be increased by using a material having a high elastic modulus as the material constituting at least one of the blank layer 10 and the adhesive layer 20, by increasing the content of the material having a high elastic modulus in at least one of the blank layer 10 and the adhesive layer 20, or the like. On the other hand, the tensile modulus can be reduced by using a material having a low elastic modulus as the material constituting at least one of the blank layer 10 and the adhesive layer 20, by increasing the content of a material having a low elastic modulus in at least one of the blank layer 10 and the adhesive layer 20, or the like.

The temperature at which the tensile modulus was measured was room temperature, and was the temperature at which the adhesive film 1 was cut using a separator. Specifically, the temperature at which the laminated sheet obtained by laminating the blank layer 10 and the adhesive layer 20 is cut and diced (see fig. 4B and 4C), and the diced laminated sheet is peeled from the pressure-sensitive adhesive layer 32 of the dicing tape 30 and picked up (see fig. 4D) corresponds to the measurement temperature of the tensile modulus.

The peel force between the adhesive layer 20 and the blank layer 10 is preferably 0.1N/20mm or more. The peeling force may be 0.5N/20mm or less.

The above peel force was measured at room temperature using a test specimen having a length of 120mm and a width of 25 mm. The peel force is a value measured under measurement conditions of a peel speed of 300 mm/min, a peel angle of 90 degrees, and a measurement temperature of 25 ℃. Specifically, the peel force was measured by the method described in the examples below.

In order to increase the peeling force, for example, a plasma surface treatment or a cleaning treatment by wiping with alcohol or the like is performed on the surface of the blank layer 10 in direct contact with the adhesive layer 20 in advance. On the other hand, in order to reduce the peeling force, for example, the surface of the spacer layer 10 is subjected to a release treatment with silicone, and the release-treated surface is superimposed on the adhesive layer 20.

The thickness (average thickness) of the laminate sheet (spacer layer and adhesive layer) may be 30 μm or more and 300 μm or less, or may be 40 μm or more and 200 μm or less.

The thickness of the laminate sheet was calculated by averaging the measured values of the thickness at least at 5 randomly selected positions.

The dicing adhesive film with spacer 1 of the present embodiment may be provided with a release tape covering one surface of the blank layer 10 (the surface of the blank layer 10 not overlapping with the adhesive layer 20) in a state before use. The release tape is used to protect the spacer layer 10, for example, by peeling it off immediately before use.

Next, the dicing tape 30 attached to the adhesive layer 20 will be described in detail.

< dicing tape for dicing adhesive film with spacer >

The dicing tape 30 is usually in a tape shape, and is used by being stretched over an annular frame having an inner diameter one turn larger than that of a silicon wafer to be subjected to dicing.

The dicing tape 30 includes a base material layer 31 and a pressure-sensitive adhesive layer 32 superposed on the base material layer 31.

The substrate layer 31 may have a single-layer structure or a laminated structure.

The base material layer 31 supports the adhesive layer 32. The base material layer 31 includes a resin. Examples of the resin contained in the base layer 31 include: polyolefins (polypropylene (PP), High Density Polyethylene (HDPE), low density polyethylene (low density polyethylene), α -olefins, etc.), ethylene-vinyl acetate copolymers (EVA), ethylene-methyl acrylate (EMA), ethylene-ethyl acrylate (EEA), ethylene-methyl methacrylate (EMMA), Styrene Butadiene Rubber (SBR), hydrogenated styrenic thermoplastic elastomers (SEBS), styrene ethylene propylene styrene block copolymers (SEPS), polyesters, polyurethanes, polycarbonates, polyether ether ketones, polyimides, polyetherimides, polyamides, wholly aromatic polyamides, polyvinyl chloride, polyvinylidene chloride, polyphenylene sulfide, fluororesins, cellulose resins, silicone resins, ionomer resins, and the like.

The base layer 31 may contain 1 kind of the above resin, or may contain 2 or more kinds.

When the pressure-sensitive adhesive layer 32 is a layer cured by ultraviolet light as described later, the base layer 31 is preferably configured to have ultraviolet light permeability.

The substrate layer 31 may be obtained by non-stretch molding or may be obtained by stretch molding. The substrate layer 31 obtained by stretch molding is preferable.

The thickness (total thickness) of the base material layer 31 is preferably 55 μm or more and 195 μm or less, more preferably 55 μm or more and 190 μm or less, further preferably 55 μm or more and 170 μm or less, and most preferably 60 μm or more and 160 μm or less.

The thickness of the base material layer 31 can be determined by measuring the thickness of 5 randomly selected points using a dial gauge (model R-205, manufactured by PEACOCK corporation) and arithmetically averaging the thicknesses.

The base layer 31 is preferably made of a resin film.

The surface of the base material layer 31 may be subjected to a surface treatment in order to improve adhesion to the pressure-sensitive adhesive layer 32. As the surface treatment, for example, oxidation treatment by a chemical method or a physical method such as chromic acid treatment, ozone exposure, flame exposure, high-voltage electric shock exposure, and ionizing radiation treatment can be used. Further, coating treatment with a coating agent such as an anchor coating agent, a primer coating agent, or an adhesive agent may be performed.

The back surface side of the base material layer 31 (the side not overlapping the pressure-sensitive adhesive layer 32) may be subjected to release treatment with a release agent (release agent) such as a silicone resin or a fluorine resin, for example, in order to impart releasability.

The base layer 31 is preferably a light-transmitting (ultraviolet-transmitting) resin film or the like in order to impart active energy rays such as ultraviolet rays to the pressure-sensitive adhesive layer 32 from the back side.

The dicing tape 30 may be provided with a release tape covering one surface of the pressure-sensitive adhesive layer 32 (the surface of the pressure-sensitive adhesive layer 32 not overlapping with the base material layer 31) in a state before use. When the adhesive layer 20 having a smaller area than the adhesive layer 32 is disposed so as to be accommodated in the adhesive layer 32, the release tape is disposed so as to cover both the adhesive layer 32 and the adhesive layer 20. The release tape is used to protect the adhesive layer 32 and is peeled off before the adhesive layer 20 is attached to the adhesive layer 32.

As the release tape, for example, a plastic film or paper surface-treated with a release agent such as silicon-based, long-chain alkyl-based, fluorine-based, or molybdenum sulfide can be used.

As the release tape, for example, a film made of a fluorine-based polymer such as polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, tetrafluoroethylene-hexafluoropropylene copolymer, chlorofluoroethylene-vinylidene fluoride copolymer; films made of polyolefins such as polyethylene and polypropylene; and films made of polyesters such as polyethylene terephthalate (PET).

As the release tape, for example, a plastic film or paper coated with a release agent such as a fluorine-based release agent or a long chain alkyl acrylate-based release agent can be used.

In the present embodiment, the adhesive layer 32 includes, for example, an acrylic polymer, an isocyanate compound, and a polymerization initiator.

The adhesive layer 32 may have a thickness of 5 μm or more and 40 μm or less. The shape and size of the pressure-sensitive adhesive layer 32 are generally the same as those of the base material layer 31.

The acrylic polymer has at least a constituent unit of an alkyl (meth) acrylate, a constituent unit of a hydroxyl group-containing (meth) acrylate, and a constituent unit of a polymerizable group-containing (meth) acrylate in the molecule. The constituent unit is a unit constituting the main chain of the acrylic polymer. Each side chain in the acrylic polymer is contained in each constituent unit constituting the main chain.

In the present specification, the expression "(meth) acrylate" means at least one of methacrylate and acrylate. Similarly, the expression "(meth) acrylic acid" means at least one of methacrylic acid and acrylic acid.

In the acrylic polymer contained in the pressure-sensitive adhesive layer 32, the above-mentioned constituent unit may be¹H-NMR、¹³NMR analysis such as C-NMR, thermal decomposition GC/MS analysis, infrared spectroscopy, and the like. The molar ratio of the above-mentioned constituent unit in the acrylic polymer is usually calculated from the amount of blending (amount added) at the time of polymerizing the acrylic polymer.

The constituent unit of the above-mentioned alkyl (meth) acrylate is derived from an alkyl (meth) acrylate monomer. In other words, the molecular structure of the alkyl (meth) acrylate monomer after the polymerization reaction is a constituent unit of the alkyl (meth) acrylate. The expression "alkyl" denotes a hydrocarbon moiety bonded to a (meth) acrylic acid ester bond.

The hydrocarbon moiety of the alkyl moiety in the constituent unit of the alkyl (meth) acrylate may be a saturated hydrocarbon or an unsaturated hydrocarbon.

The alkyl moiety preferably does not contain a polar group containing oxygen (O), nitrogen (N), or the like. This can suppress an extreme increase in polarity of the alkyl polymer. Therefore, the adhesive layer 32 can be suppressed from having excessive affinity for the adhesive layer 20. Therefore, the dicing tape 30 can be more favorably peeled from the adhesive layer 20. The number of carbon atoms in the alkyl moiety may be 6 to 10 (C6-10 alkyl).

Examples of the constituent unit of the alkyl (meth) acrylate include: hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-nonyl or isononyl (meth) acrylate, decyl (meth) acrylate, and the like.

The acrylic polymer has a constituent unit of a hydroxyl group-containing (meth) acrylate, and the hydroxyl group of the constituent unit is easily reacted with an isocyanate group.

By allowing an acrylic polymer having a constituent unit of a hydroxyl group-containing (meth) acrylate and an isocyanate compound to coexist in the pressure-sensitive adhesive layer 32, the pressure-sensitive adhesive layer 32 can be appropriately cured. Therefore, the acrylic polymer can be sufficiently gelled. Therefore, the adhesive layer 32 can exert adhesive performance while maintaining the shape.

The constituent unit of the hydroxyl group-containing (meth) acrylate is preferably a constituent unit of a hydroxyl group-containing C2-C4 alkyl (meth) acrylate. The expression "C2-C4 alkyl" refers to the number of carbon atoms of the hydrocarbon moiety bonded to the (meth) acrylic acid via an ester bond. In other words, the hydroxyl group-containing C2-C4 alkyl (meth) acrylate monomer is a monomer obtained by ester-bonding (meth) acrylic acid and an alcohol having 2 to 4 carbon atoms (usually 2-membered alcohol).

The hydrocarbon moiety of the C2-C4 alkyl group is typically a saturated hydrocarbon. For example, the hydrocarbon moiety of the C2-C4 alkyl group is a straight-chain saturated hydrocarbon or a branched-chain saturated hydrocarbon. The hydrocarbon moiety of the C2-C4 alkyl group preferably does not contain a polar group containing oxygen (O), nitrogen (N), or the like.

Examples of the structural unit of the hydroxyl group-containing C2-C4 alkyl (meth) acrylate include: and a hydroxybutyl (meth) acrylate such as hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxy-n-butyl (meth) acrylate or hydroxyisobutyl (meth) acrylate. In the constitutional unit of hydroxybutyl (meth) acrylate, a hydroxyl group (-OH group) may be bonded to a carbon (C) at the end of a hydrocarbon moiety, or may be bonded to a carbon (C) other than the end of the hydrocarbon moiety.

The acrylic polymer contains a constituent unit of a polymerizable group-containing (meth) acrylate having a polymerizable unsaturated double bond in a side chain.

When the acrylic polymer contains a constituent unit of a polymerizable group-containing (meth) acrylate, the pressure-sensitive adhesive layer 32 can be cured by irradiation with active energy rays (ultraviolet rays or the like) before the pickup step. Specifically, the photopolymerization initiator generates radicals by irradiation with active energy rays such as ultraviolet rays, and the acrylic polymers are subjected to a crosslinking reaction by the action of the radicals. This makes it possible to reduce the adhesive force of the pressure-sensitive adhesive layer 32 before irradiation by irradiation. Further, the adhesive layer 20 can be favorably peeled from the adhesive layer 32.

As the active energy ray, ultraviolet rays, radiation rays, and electron rays can be used.

Specifically, the constituent unit of the polymerizable group-containing (meth) acrylate may have a molecular structure in which an isocyanate group of an isocyanate group-containing (meth) acrylate monomer and a hydroxyl group of the constituent unit of the hydroxyl group-containing (meth) acrylate are bonded to each other via a urethane bond.

The constituent unit of the polymerizable group-containing (meth) acrylate having a polymerizable group can be prepared after polymerization of the acrylic polymer. For example, the polymerizable group-containing (meth) acrylate constituent unit can be obtained by copolymerizing an alkyl (meth) acrylate monomer and a hydroxyl group-containing (meth) acrylate monomer, and then subjecting a hydroxyl group in a part of the constituent unit of the hydroxyl group-containing (meth) acrylate and an isocyanate group of an isocyanate group-containing polymerizable monomer to a urethanization reaction.

The isocyanate group-containing (meth) acrylate monomer preferably has 1 isocyanate group and 1 (meth) acryloyl group in the molecule. Examples of the monomer include 2-isocyanatoethyl (meth) acrylate.

The adhesive layer 32 of the dicing tape 30 of the present embodiment further contains an isocyanate compound. Part of the isocyanate compound may be in a state after reaction by a urethanization reaction or the like.

The isocyanate compound has a plurality of isocyanate groups in a molecule. By having a plurality of isocyanate groups in a molecule of the isocyanate compound, a crosslinking reaction between the acrylic polymers in the pressure-sensitive adhesive layer 32 can be performed. Specifically, the crosslinking reaction by the isocyanate compound can be performed by reacting one isocyanate group of the isocyanate compound with a hydroxyl group of the acrylic polymer and reacting the other isocyanate group with a hydroxyl group of the other acrylic polymer.

Examples of the isocyanate compound include: diisocyanates such as aliphatic diisocyanate, alicyclic diisocyanate, and araliphatic diisocyanate.

Further, examples of the isocyanate compound include: polymeric polyisocyanates such as dimers and trimers of diisocyanates, polymethylene polyphenylene polyisocyanates.

Examples of the isocyanate compound include polyisocyanates obtained by reacting an excess of the isocyanate compound with an active hydrogen-containing compound. Examples of the active hydrogen-containing compound include an active hydrogen-containing low molecular weight compound and an active hydrogen-containing high molecular weight compound.

As the isocyanate compound, allophanate polyisocyanate, biuret polyisocyanate, or the like can be used.

The isocyanate compounds can be used alone in 1 or more than 2 combination.

As the isocyanate compound, a reaction product of an aromatic diisocyanate and an active hydrogen-containing low molecular weight compound is preferable. Since the reaction rate of the aromatic diisocyanate is low, excessive curing of the adhesive layer 32 containing the reactant can be suppressed. The isocyanate compound is preferably one having 3 or more isocyanate groups in the molecule.

The polymerization initiator contained in the adhesive layer 32 is a compound that can initiate polymerization reaction by applied thermal energy, light energy. By including the polymerization initiator in the adhesive layer 32, a crosslinking reaction between acrylic polymers can be performed when thermal energy or light energy is applied to the adhesive layer 32. Specifically, the pressure-sensitive adhesive layer 32 can be cured by initiating a polymerization reaction between polymerizable groups in an acrylic polymer having a constituent unit of a polymerizable group-containing (meth) acrylate. This can reduce the adhesive strength of the adhesive layer 32, and the adhesive layer 20 can be easily peeled from the cured adhesive layer 32 in the pickup step.

As the polymerization initiator, for example, a photopolymerization initiator, a thermal polymerization initiator, or the like can be used. As the polymerization initiator, conventional commercially available products can be used.

The adhesive layer 32 may further contain other components in addition to the above components. Examples of the other components include: an adhesion promoter, a plasticizer, a filler, an antioxidant, an ultraviolet absorber, a light stabilizer, a heat stabilizer, an antistatic agent, a surfactant, a light release agent, and the like. The kind and amount of the other components may be appropriately selected depending on the purpose.

The dicing adhesive Film 1 with spacers according to the present embodiment is preferably used for embedding a semiconductor chip w' with an adhesive layer 20 when manufacturing a semiconductor integrated circuit of a chip embedded type (FOD [ Film On Die, thin Film On chip ] type). More specifically, the dicing adhesive film 1 with spacers is preferably used by bonding the adhesive layer 20 to the substrate Z so that the semiconductor chip w' is embedded in the adhesive layer 20 (see fig. 1C, 5A, and the like).

In the present embodiment, since the dicing adhesive film 1 with spacers having the spacer layer 10 made of resin or the like can be used for the above-described applications, the manufacturing process of the semiconductor integrated circuit can be shortened as compared with the conventional processing film using a Si wafer as the spacer layer. Specifically, there is no need to perform a series of steps of attaching a back grinding tape to an Si wafer and processing the Si wafer to a desired thickness by back grinding. Further, the spacer layer can be manufactured without being affected by the shortage of the Si wafer supply, and can be manufactured by using a relatively inexpensive resin.

Alternatively, the dicing adhesive Film 1 with spacers according to the present embodiment may be used by bonding the adhesive layer 20 to the substrate Z in order to secure a space for stacking the NAND chip w ″ for memory above the NAND chip w' for control in manufacturing a buried-Wire type semiconductor integrated circuit (FOW [ Film On Wire, thin-Film-On-Wire ] type semiconductor integrated circuit) (see fig. 5B to 5E, etc.). In this case, the dicing adhesive film 1 with spacers can be used by bonding the adhesive layer 20 to the substrate Z so that the bonding wires L are embedded in the adhesive layer 20. Thus, for the same reason as described above, there is an advantage that the manufacturing process of the semiconductor integrated circuit can be shortened, and there is an advantage that the spacer layer can be formed without being affected by the shortage of the Si wafer supply.

Next, a method for producing the dicing adhesive film 1 with spacers according to the present embodiment will be described.

< method for producing dicing adhesive film with spacer >

The method for producing the dicing adhesive film 1 with spacers according to the present embodiment includes the steps of:

a process for producing the spacer layer 10 is described,

a step of producing the adhesive layer 20 by a dry process,

a process for producing the dicing tape 30, and

and a step of overlapping the produced blank layer 10, adhesive layer 20, and dicing tape 30.

(Process for producing spacer layer)

The step of forming the spacer layer 10 may include, for example, the following steps: a resin composition preparation step of preparing a resin composition for forming the spacer layer 10, and a spacer layer forming step of forming the spacer layer 10 from the resin composition.

On the other hand, a commercially available resin film may be used as the spacer layer 10.

(Process for producing adhesive layer)

The step of producing the adhesive layer 20 includes the steps of:

a resin composition preparation step of preparing a resin composition for forming the adhesive layer 20, and

and an adhesive layer forming step of forming the adhesive layer 20 from the resin composition.

The resin composition preparation step is, for example, to prepare a resin composition by mixing an epoxy resin, a curing catalyst for an epoxy resin, an acrylic resin, a phenol resin, a solvent, and the like, and dissolving each resin in the solvent. By varying the amount of solvent, the viscosity of the composition can be adjusted. As these resins, commercially available products may be used.

In the adhesive layer forming step, for example, the resin composition prepared as described above is applied to a release sheet. The coating method is not particularly limited, and a conventional coating method such as roll coating, screen coating, gravure coating, or the like can be used. Next, the applied composition is cured by a desolvation treatment, a curing treatment, or the like as necessary, to form the adhesive layer 20.

In the adhesive layer forming step, the adhesive layer 20 may be formed so as to overlap the blank layer 10 by applying the resin composition prepared as described above to the blank layer 10.

(Process for producing dicing tape)

The step of manufacturing the dicing tape 30 includes the steps of:

a synthesis step for synthesizing an acrylic polymer,

a pressure-sensitive adhesive layer production step of producing the pressure-sensitive adhesive layer 32 by volatilizing a solvent from a pressure-sensitive adhesive composition containing the acrylic polymer, the isocyanate compound, the polymerization initiator, the solvent, and other components added as appropriate depending on the purpose,

a substrate layer production step of producing the substrate layer 31, and

and a bonding step of bonding the adhesive layer 32 to the base material layer 31.

In the synthesis step, for example, an acrylic polymer intermediate is synthesized by radical polymerization of an alkyl (meth) acrylate monomer and a hydroxyl group-containing (meth) acrylate monomer.

The radical polymerization can be carried out by conventional methods. For example, an acrylic polymer intermediate can be synthesized by dissolving the above monomers in a solvent, stirring the solution while heating, and adding a polymerization initiator. In order to adjust the molecular weight of the acrylic polymer, the polymerization may be carried out in the presence of a chain transfer agent.

Next, a part of the hydroxyl groups of the constituent units of the hydroxyl group-containing (meth) acrylate included in the acrylic polymer intermediate and the isocyanate groups of the isocyanate group-containing polymerizable monomer are bonded by a urethanization reaction. Thus, a part of the constituent unit of the hydroxyl group-containing (meth) acrylate becomes the constituent unit of the polymerizable group-containing (meth) acrylate.

The carbamation reaction can be carried out by a conventional method. For example, the acrylic polymer intermediate and the isocyanate group-containing polymerizable monomer are stirred while heating in the presence of a solvent and a urethane-forming catalyst. In this way, the isocyanate group of the isocyanate group-containing polymerizable monomer can be bonded to a part of the hydroxyl group of the acrylic polymer intermediate by a urethane bond.

In the pressure-sensitive adhesive layer producing step, for example, an acrylic polymer, an isocyanate compound, and a polymerization initiator are dissolved in a solvent to prepare a pressure-sensitive adhesive composition. By varying the amount of solvent, the viscosity of the composition can be adjusted. Next, the adhesive composition is applied to a release sheet. As the coating method, for example, a conventional coating method such as roll coating, screen coating, gravure coating, or the like can be used. The adhesive layer 32 is produced by subjecting the applied composition to a desolvation treatment, a curing treatment, or the like, thereby curing the applied adhesive composition.

In the substrate layer production step, the substrate layer 31 can be produced by film formation by a conventional method. Examples of the method for forming a film include: a calendering film-forming method, a casting method in an organic solvent, a inflation extrusion method in a closed system, a T-die extrusion method, a dry lamination method, and the like. A co-extrusion molding method may be employed. As the base layer 31, a commercially available film or the like may be used.

In the bonding step, the pressure-sensitive adhesive layer 32 in a state of being overlapped with the release sheet is overlapped with the base material layer 31 to be laminated. The release sheet may be in a state of being overlapped with the adhesive layer 32 until the use.

In order to promote the reaction between the crosslinking agent and the acrylic polymer and the reaction between the crosslinking agent and the surface portion of the base material layer 31, a curing step may be performed at 50 ℃ for 48 hours after the bonding step.

Through these processes, the dicing tape 30 can be manufactured.

(step of superposing the adhesive layer with spacer layer on the dicing tape)

In the step of overlapping the adhesive layer 20 and the dicing tape 30, the adhesive layer 20 is attached to the adhesive layer 32 of the dicing tape 30 manufactured as described above.

In this attachment, the release sheet is peeled from the pressure-sensitive adhesive layer 32 and the adhesive layer 20 of the dicing tape 30, respectively, and the adhesive layer 20 and the pressure-sensitive adhesive layer 32 are bonded to each other so as to be in direct contact with each other. For example, the bonding may be performed by crimping. The temperature at the time of bonding is not particularly limited, and is, for example, 30 ℃ to 50 ℃, preferably 35 ℃ to 45 ℃. The line pressure at the time of bonding is not particularly limited, but is preferably 0.1kgf/cm or more and 20kgf/cm or less, and more preferably 1kgf/cm or more and 10kgf/cm or less.

< method for producing dicing adhesive film with spacer (specific example) >

As shown in fig. 2 and 3, the dicing adhesive film with spacer 1 of the present embodiment is formed by stacking a stack of a blank layer 10 and an adhesive layer 20 on one surface of a long sheet-like dicing tape 30. The laminated sheets (blank layer 10 and adhesive layer 20) overlapping the dicing tape 30 are circular when viewed in the thickness direction, and a plurality of laminated sheets are aligned in a line in the longitudinal direction of the dicing tape 30. The dicing adhesive film 1 with spacers of this form can be produced, for example, by using the release tape H and the transfer tape T as follows.

The dicing adhesive film 1 with spacers can be manufactured by using, for example, the respective apparatuses (I, I', I ") shown in fig. 7A, 8A, and 9A.

First, as shown in fig. 6A, the aforementioned resin composition is applied to the blank layer 10 (for example, a resin film), and the solvent is volatilized from the resin composition, thereby producing the adhesive layer 20 that overlaps the blank layer 10. Next, the release tape H is stuck to the adhesive layer 20, and as shown in fig. 6B, a tape-shaped laminate with the release tape H is produced. The spacer layer 10 may be superposed on the adhesive layer 20 prepared in the same manner by applying the resin composition to the release tape H, whereby a similar laminated sheet can be prepared.

Next, the laminated sheet of the blank layer 10 and the adhesive layer 20 is mounted to the device shown in fig. 7A. At this time, as shown in fig. 7B, the laminate sheet is disposed with the release tape H positioned on the lower side. While the laminate sheet is fed into the apparatus, the transfer belt T is superposed on the spacer layer 10. At this stage, the sheet obtained by bonding the release tape H, the blank layer 10, the adhesive layer 20, and the transfer tape T is temporarily wound.

Further, the temporarily bonded sheet is attached to the apparatus shown in fig. 8A. At this time, as shown in fig. 8B, the transfer belt T is disposed on the lower side. While the laminated sheet is fed into the apparatus, the release tape H and the laminated sheet are die-cut into a circular shape (predetermined shape) by a punching process. Next, the release tape H except for the portion punched out into a circular shape (release tape H of the peripheral portion except for the circular portion) is removed by rolling. Then, the tape S is pasted and removed while the remaining portion of the pasted sheet is moved in the downstream direction by the apparatus. By winding up the temporarily attached removal tape S, unnecessary portions of the laminate sheet are removed so that a thin disc-shaped laminate sheet remains on the transfer belt T (see fig. 8C). Next, the dicing tape 30 is superimposed on the plurality of thin spacer layers 10 so as to cover the plurality of laminated sheets arranged apart from each other (see fig. 8D). At this time, the pressure-sensitive adhesive layer 32 of the dicing tape 30 is attached so as to be in direct contact with the adhesive layer 20. At this stage, the sheet in which the blank layer 10, the adhesive layer 20, and the transfer belt T are bonded is temporarily wound. As a result, the transfer belt T is stuck to the dicing adhesive film 1 of the tape spacer in which the dicing tape 30, the adhesive layer 20, and the spacer layer 10 are laminated. This state may be used as the final target, or the transfer belt T may be temporarily taken up to remove the transfer belt T, and the following operation may be further performed.

Then, the cut adhesive film 1 (tape transfer belt T) of the temporarily wound tape spacer is attached to the apparatus shown in fig. 9A. At this time, as shown in fig. 9B, the transfer belt T is disposed on the upper side, and the dicing belt 30 is disposed on the lower side. The transfer belt T is removed while feeding the dicing adhesive film 1 with spacers into the apparatus (see fig. 9C). Further, the separation tape H may be overlapped on the spacer layer 10 in order to protect the exposed spacer layer 10 (see fig. 9D).

In fig. 7A, 8A, and 9A, the feeding direction when feeding a long sheet to each apparatus and the winding direction when collecting a long sheet are not particularly limited. Specifically, the long wound sheet disposed on the most upstream side of each apparatus may be fed such that the inner peripheral side surface faces upward, or the outer peripheral side surface faces upward. The long sheet to be wound, which is disposed on the most downstream side of each apparatus, may be collected so that the upper surface faces the inner circumferential side, or may be collected so that the upper surface faces the outer circumferential side.

Further, the dicing adhesive film 1 with spacers manufactured by the above-described apparatus can be further processed. For example, the dicing adhesive film 1 with spacers may be subjected to a slitting process (fig. 10A) of removing both ends in the width direction according to the standard width of the product, and then a precutting process (see fig. 10B) of punching the dicing tape 30 from above into a predetermined shape and removing unnecessary dicing tape 30 by using a punching device (not shown) with a dimension slightly larger (for example, 1.1 times or more and 1.4 times or less) than the circular punching portion (the punching portion of the adhesive layer 20 and the blank layer 10).

The dicing adhesive film 1 with spacers manufactured as described above is used as an auxiliary tool for manufacturing a semiconductor integrated circuit, for example. The dicing adhesive film 1 with spacers is used particularly in the following 2 nd step. Specific examples of the use will be described below.

< method of using dicing adhesive film with spacer in production of semiconductor integrated circuit >

A method of manufacturing a semiconductor integrated circuit generally includes a step of cutting out chips from a semiconductor wafer on which a circuit surface is formed and assembling the chips.

The process includes, for example, the following steps:

a step 1 of cutting out a controller chip w' for control from a semiconductor wafer (bare wafer) and fixing the chip on the surface of a substrate Z;

a 2 nd step of cutting out a small piece of the spacer layer 10 with the adhesive layer 20 attached thereto from the laminated sheet in which the adhesive layer 20 and the spacer layer 10 are laminated, fixing the cut piece on the surface of the substrate Z, and forming a base for stacking a plurality of NAND chips w ″ for memory by the spacer layer 10; and

in the 3 rd step, the NAND chip w ″ for memory is cut out from the semiconductor wafer (bare wafer), and a plurality of NAND chips w ″ for memory are stacked on the spacer layer 10.

The dicing adhesive film 1 with spacers according to the present embodiment is used, for example, in the above-described step 2.

The 1 st step includes, for example, the following steps for fixing the controller chip w' for control to the surface of the adherend (substrate Z): a step of performing a half-cut process of thinning the semiconductor wafer by grinding after forming a groove in the semiconductor wafer in order to process the semiconductor wafer into chips w' (chip, die) by a cleaving process; a step of attaching one surface (for example, the surface opposite to the circuit surface) of the thinned semiconductor wafer to the dicing tape 30 to fix the semiconductor wafer to the dicing tape 30; a step of enlarging the interval between the semi-cut semiconductor chips to reduce the semiconductor wafer into chips; a taking-out step of picking up the semiconductor chip w '(chip, die) in a state where the chip bonding layer d' is adhered; and a step of bonding (die bonding) the semiconductor chip w '(chip, die) in a state where the die bonding layer d' is adhered to an adherend (see fig. 1A).

The dicing tape 30 (dicing adhesive film with spacers) of the present embodiment is used as a manufacturing aid when the following step in the step 2 is performed.

The 2 nd step includes, for example, the following steps for fixing the bank layer 10 and the adhesive layer 20 to the surface of the adherend (substrate Z): a step of attaching a dicing ring R to a dicing tape 30 of the dicing adhesive film 1 with spacers (see fig. 4A); a step of performing a blade cutting process on the adhesive layer 20 and the blank layer 10 with a dicing saw B to cut them into small pieces (die) (see fig. 4B and 4C); a step of peeling the diced blank layer 10 with the adhesive layer 20 adhered thereto from the adhesive layer 32 of the dicing tape 30 by an adsorption jig J and picking up the resultant (see fig. 4D); and a step of bonding the blank layer 10 in a state where the adhesive layer 20 is adhered to an adherend (substrate Z) (see fig. 1B).

In the 3 rd step, in order to superimpose the NAND chip w for storage on the spacer layer 10 plural times, for example, the NAND chip w for storage is picked up and bonded to the adherend (spacer layer 10) in the same manner as in the 1 st step, and further the NAND chip w for storage is superimposed (see fig. 1C).

In the semiconductor industry in recent years, the capacity per unit area of a NAND chip is increasing with the further development of integration technology. Along with this, the size of NAND chips is becoming smaller and smaller if the same capacity is used. For example, in a semiconductor integrated circuit of a type in which a memory NAND chip w ″ is stacked on a control NAND chip w ', if the memory NAND chip w ″ is reduced in size, it may be difficult to embed the control NAND chip w' in the memory NAND chip w ″, which may make it difficult to assemble the semiconductor integrated circuit.

In contrast, the dicing adhesive film 1 with spacers according to the present embodiment can be used to secure a space for stacking the NAND chips w ″ for storage.

The dicing adhesive film 1 with spacers according to the present embodiment can be used for dicing the laminated sheet, peeling the diced laminated sheet from the dicing tape 30, and picking up the same as the dicing die bonding film used when manufacturing semiconductor chips from bare wafers. Then, the picked-up laminate sheet is bonded to an adherend such as the substrate Z, for example, and the NAND chip w ″ for storage is stacked on the spacer layer 10 of the laminate sheet.

The form of the semiconductor integrated circuit to be manufactured is not limited to the form shown in fig. 1C, and may be, for example, the forms shown in fig. 5A to 5E.

The dicing adhesive film with spacers according to the present embodiment is exemplified as described above, but the present invention is not limited to the dicing adhesive film with spacers exemplified above.

That is, various forms used for the conventional dicing adhesive film with spacers can be adopted within a range not to impair the effects of the present invention.

The disclosure of the present specification includes the following aspects.

(1) A dicing adhesive film with a spacer, comprising:

a laminate sheet having an adhesive layer for adhering to an adherend and a spacer layer superposed on the adhesive layer; and

a dicing tape which is overlapped with the adhesive layer of the laminated sheet and holds the laminated sheet,

the laminate sheet has a bending rigidity of 0.05 N.mm at room temperature²The above.

(2)

The dicing adhesive film with a spacer according to the item (1), wherein the laminate sheet has an elastic modulus of 1GPa or more.

(3)

The dicing adhesive film with a spacer according to the item (2), wherein a peeling force between the adhesive layer and the blank layer is 0.1N/20mm or more.

(4)

The dicing adhesive film with a spacer according to any one of the above (1) to (3), wherein the thickness of the spacer layer is 3 μm or more and 300 μm or less.

(5)

The dicing adhesive film with a spacer according to any one of the above (1) to (4), wherein the adhesive layer has a thickness of 10 μm or more and 200 μm or less.

(6)

The dicing adhesive film with a spacer according to any one of the above (1) to (5), wherein the spacer layer is made of at least 1 material selected from the group consisting of polyimide, polyamideimide, polyester, polybenzimidazole, polyetherimide, polyphenylene sulfide and polyether ether ketone.

(7)

The dicing adhesive film with a spacer according to any one of the above (1) to (6), wherein the adhesive layer contains a thermosetting resin and a thermoplastic resin.

(8)

The dicing adhesive film with spacers according to the item (7), wherein the adhesive layer further contains a filler.

(9)

The dicing adhesive film with spacers according to the item (8), wherein the adhesive layer contains a filler in a proportion of 30 to 70 mass% based on the total mass of the adhesive layer.

(10)

The dicing adhesive film with a spacer according to any one of the above (1) to (9), wherein the pressure-sensitive adhesive layer of the dicing tape contains an acrylic polymer, an isocyanate compound, and a polymerization initiator.

(11)

The dicing bonding film with a spacer according to the item (10), wherein the acrylic polymer contained in the pressure-sensitive adhesive layer contains a constituent unit of a polymerizable group-containing (meth) acrylate having a polymerizable unsaturated double bond in a side chain.

(12)

The dicing adhesive film with spacers according to any one of the above (1) to (11), which is used for embedding a semiconductor chip when manufacturing a chip-embedded semiconductor integrated circuit or for securing a space for stacking a memory semiconductor chip on a control semiconductor chip when manufacturing a buried-type semiconductor integrated circuit.

Examples

The present invention will be described in more detail with reference to the following experimental examples, but the present invention is not limited thereto.

(examples 1 to 6 and comparative example 1)

The laminated sheet of the blank layer and the adhesive layer was produced as follows. Further, the adhesive layer of the laminate sheet was bonded to a dicing tape, and dicing adhesive films with spacers having the compositions shown in table 1 were produced.

< spacer layer >

As the spacer layer, the following resin film was prepared.

Polyimide film A (thickness 75 μm)

(product name "kapton 300V" DU PONT-TORAY Co., manufactured by Ltd.)

Polyimide film B (thickness 25 μm)

(product name "kapton 100H" DU PONT-TORAY Co., manufactured by Ltd.)

Polyamide-imide film (thickness 4 μm)

(product name "Mictron #4Y-GE 10" manufactured by Toray corporation)

Para-aromatic polyamide (aramid) film

Polyethylene terephthalate film A (Single-sided silicone treatment with a thickness of 50 μm)

(attaching untreated surface to adhesive layer)

(product name "DIAFOIL MRA 50" manufactured by Mitsubishi chemical corporation)

Polyethylene terephthalate film B (Single-sided silicone treatment with a thickness of 50 μm)

(attaching the Silicone-treated surface to the adhesive layer)

(product name "DIAFOIL MRA 50" manufactured by Mitsubishi chemical corporation)

< preparation of adhesive layer >

Methyl ethyl ketone was added to the following raw materials and mixed to obtain a composition for an adhesive layer. Details of each raw material are as follows.

100 parts by mass of an acrylic acid ester polymer solution

Product name "Teisan Resin SG-70L" (solid content concentration 12.8 mass%)

Nagase ChemteX Corporation containing carboxyl and hydroxyl groups in the molecule

1.7 parts by mass of an epoxy resin

Product name "EPIKOTE YL 980" manufactured by Mitsubishi chemical corporation

13 parts by mass of an epoxy resin

Product name "EPICLON N-665-EXP-S" DIC Co., Ltd

15 parts by mass of a phenolic resin (curing agent)

Product name "MEHC-7851 SS" manufactured by KANGCHE CHEMICAL CO., LTD

47 parts by mass of silica organic solvent slurry (containing 60% by mass of powder)

The product name "SO-E2" (obtained by dispersing powder in MEK in advance)

Admatechs, co, ltd

0.085 part by mass of a curing catalyst

The product name "Curezol 2 PHZ" manufactured by four national chemical industry Co., Ltd

50 parts by mass of MEK (methyl ethyl ketone) as a diluent solvent

Next, one surface of the following coating substrate was coated with the adhesive layer composition using an applicator. The coating was performed so that the thickness after drying was 120 μm, and then the solvent was volatilized from the composition for adhesive layer by drying treatment at 120 ℃ for 2 minutes. Thus, an adhesive layer superposed on the substrate for coating was obtained.

Production of coated substrate (release sheet) product name "PET 38" Fujiko co

An intermediate layer is bonded to the exposed surface of the adhesive layer.

< adhesive layer of dicing tape >

(preparation of adhesive layer (adhesive composition))

The following raw materials were prepared.

2EHA (2-ethylhexyl acrylate): 100 parts by mass

HEA (2-hydroxyethyl acrylate): 20 parts by mass

AIBN (2, 2' -azobisisobutyronitrile): proper amount of

Polymerization solvent (toluene): such that the monomer concentration is about 55 mass%

The above-mentioned raw materials were put into a separable round-bottom flask (volume: 1L) of a polymerization experimental apparatus equipped with a thermometer, a nitrogen inlet, and a stirrer. While nitrogen gas was introduced into a round-bottomed separable flask with stirring, polymerization was carried out at 60 ℃ for 10 hours to prepare an intermediate composition.

After cooling the intermediate composition to room temperature, the following raw materials were added to 100 parts by mass of the intermediate composition.

2-Methacryloyloxyethyl isocyanate

The raw material name "Karenz MOI", manufactured by Showa Denko K.K.): 1.4 parts by mass

Dibutyltin dilaurate IV (manufactured by wako pure chemical industries, ltd.): 0.1 part by mass

The mixture was stirred at 50 ℃ for 60 hours under an atmospheric atmosphere to obtain an acrylic polymer composition.

Finally, the following raw materials were added to 100 parts by mass of the solid content of the acrylic polymer composition to obtain a pressure-sensitive adhesive composition for forming a pressure-sensitive adhesive layer.

An isocyanate compound (raw material name "CORONATE L", manufactured by tokyo co., ltd.): 1.1 parts by mass

Photopolymerization initiator (raw material name "IRGACURE 184", manufactured by IGM Resins corporation): 3 parts by mass

Toluene: the viscosity of the composition is about 500 mPas

As a release sheet, a PET film was prepared. The adhesive composition was coated on one surface of the PET film (subjected to mold release treatment) using an applicator so that the thickness after drying was 30 μm. The film was dried by heating at 120 ℃ for 2 minutes to form an adhesive layer superposed on the PET film (release sheet).

< preparation of dicing tape >

As the substrate layer, a polyethylene film having a thickness of 80 μm was prepared. The polyethylene film was laminated to the adhesive layer on the PET film prepared as described above at room temperature using a laminator. Thus, a dicing tape was manufactured.

< production of dicing adhesive film with spacer >

A dicing adhesive film provided with a spacer layer, an adhesive layer, and a dicing tape spacer was produced by bonding the adhesive layer of the dicing tape and the adhesive layer with the spacer layer at 70 ℃.

Specifically, the blank layer and the adhesive layer (thickness 120 μm) were bonded at 70 ℃ to prepare a laminate sheet. The laminate was cut into a circular shape having a diameter of 330 mm. The cut laminate was then attached to a dicing tape at room temperature.

The dicing adhesive films with spacers of examples and comparative examples were produced in the same manner as described above. Details of the structure of each film are shown in table 1.

< measurement of elastic modulus (tensile modulus) of blank layer and adhesive layer (laminate sheet) >

The blank layer and the adhesive layer (laminated sheet) of each of examples and comparative examples were cut into a long shape having a length of 40mm and a width of 10mm by a utility knife. Then, the tensile storage modulus from-30 ℃ to 300 ℃ was measured using a solid viscoelasticity measuring apparatus (RSAIII, manufactured by Rheometric Scientific Inc.). The measuring conditions adopt the frequency of 1Hz, the temperature rising speed of 10 ℃/min and the chuck interval of 20.0 mm. Then, the value of the storage modulus at 25 ℃ was read as the elastic modulus.

< calculation of bending stiffness of blank layer and adhesive layer (laminate sheet) >

The flexural rigidity of the laminated sheets of the examples and comparative examples was calculated based on the elastic modulus measured as described above and the formula (1) and the like.

In example 1, the bending stiffness was calculated using, for example, b of 12[ mm ], F of 2300[ MPa ], h of 0.195[ mm ], and λ of 0.0975[ mm ] as the respective values in formula (1). b-12 [ mm ] corresponds to the length of the long side of the test specimen in the usability test described later.

< measurement of peeling force between blank layer and adhesive layer >

The blank layer and the adhesive layer (laminate sheet) of each of examples and comparative examples were cut into long strips 120mm in length and 25mm in width by a utility knife. A double-sided adhesive tape was attached to the SUS plate, and a laminate sheet cut into a long strip shape was attached to the double-sided adhesive tape. At this time, the adhesive layer is attached to the double-sided tape. Next, the peel strength between the blank layer and the adhesive layer was measured by using a precision universal tester product name "Autograph AGS-J" (manufactured by Shimadzu corporation). The measurement conditions used were a peeling speed of 300 mm/min, a peeling angle of 90 degrees, and a measurement temperature of 25 ℃. Then, the measurement value was converted into a value of 20mm with respect to the width.

[ Table 1]

< evaluation of service Properties >

Each of the manufactured dicing adhesive films with spacers was diced using DFD6361 manufactured by DISCO Corporation. Dicing was performed to obtain chip-shaped spacer layers and adhesive layers (laminated sheets) of 6.0mm × 12.0 mm. As the cutting blades, Z1 used 2030-SE27 HCDD and Z2 used 2030-SE27 HCBB, and the ladder cutting was performed. Regarding the blade height, the adhesive layer was half-cut with a Z1 blade, and then the dicing tape was cut with a Z2 blade by 20 μm.

(evaluation of pickup Properties)

20 small laminated sheets were picked up at room temperature using a die bonder DB830plus + manufactured by fasfrd techlology co.

[ pickup Condition ]

Jacking up the clamp: multi-stage pickup, stage number: 3. the size of the clamp is as follows: 6mm x 12mm

Jacking amount: 300 μm at 1 st stage, 600 μm at 2 nd stage, 900 μm at 3 rd stage

Jacking speed: 5 mm/sec

The expansion amount is as follows: 3mm

The results of performance evaluation (pickup performance) of the dicing adhesive films with spacers of the examples and comparative examples are shown in table 1.

From the above evaluation results, it is clear that the dicing adhesive film with spacers including the blank layer of the example is better in pickup performance than the dicing adhesive film with spacers of the comparative example.

In the examples, the flexural rigidity of the laminate sheets (blank layer and adhesive layer) at room temperature (25 ℃ C.) was 0.05 N.mm²As described above.

By using the dicing adhesive film with spacers of the embodiment having such physical properties in the manufacture of a semiconductor integrated circuit, a so-called NAND flash memory or the like can be manufactured efficiently.

Industrial applicability

The dicing adhesive film with spacers of the present invention is suitably used as an auxiliary tool in manufacturing a semiconductor integrated circuit, for example.

Claims

1. A dicing adhesive film with a spacer, comprising:

a laminate sheet having an adhesive layer for adhering to an adherend and a spacer layer superposed on one surface of the adhesive layer; and the number of the first and second groups,

a dicing tape that overlaps and holds the laminated sheet on the other surface of the adhesive layer of the laminated sheet,

the laminate sheet has a flexural rigidity of 0.05 N.mm at room temperature²The above.

2. The spacer-equipped dicing adhesive film according to claim 1, wherein the laminate sheet has an elastic modulus of 1GPa or more.

3. The spacer-equipped dicing adhesive film according to claim 1 or 2, wherein a peel force between the adhesive layer and the blank layer is 0.1N/20mm or more.

4. The dicing adhesive film with spacer according to claim 1 or 2, wherein the thickness of the spacer layer is 3 μm or more and 300 μm or less.

5. The dicing adhesive film with spacer according to claim 1 or 2, wherein the thickness of the adhesive layer is 10 μm or more and 200 μm or less.

6. The spacer-equipped dicing bonding film according to claim 1 or 2, wherein the spacer layer is made of at least 1 material selected from the group consisting of polyimide, polyamideimide, polyester, polybenzimidazole, polyetherimide, polyphenylene sulfide and polyether ether ketone.

7. The dicing adhesive film with spacers according to claim 1 or 2, which is used for embedding a semiconductor chip when manufacturing a semiconductor integrated circuit of a chip-embedded type or for securing a space for stacking a semiconductor chip for memory on a semiconductor chip for control when manufacturing a semiconductor integrated circuit of a buried wire type.