CN109473391A - Air bridges manufacturing method - Google Patents
Air bridges manufacturing method Download PDFInfo
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- CN109473391A CN109473391A CN201811337306.0A CN201811337306A CN109473391A CN 109473391 A CN109473391 A CN 109473391A CN 201811337306 A CN201811337306 A CN 201811337306A CN 109473391 A CN109473391 A CN 109473391A
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- photoresist layer
- exposure
- air bridges
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- pontic
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/70—Manufacture or treatment of devices consisting of a plurality of solid state components formed in or on a common substrate or of parts thereof; Manufacture of integrated circuit devices or of parts thereof
- H01L21/71—Manufacture of specific parts of devices defined in group H01L21/70
- H01L21/768—Applying interconnections to be used for carrying current between separate components within a device comprising conductors and dielectrics
- H01L21/76801—Applying interconnections to be used for carrying current between separate components within a device comprising conductors and dielectrics characterised by the formation and the after-treatment of the dielectrics, e.g. smoothing
- H01L21/7682—Applying interconnections to be used for carrying current between separate components within a device comprising conductors and dielectrics characterised by the formation and the after-treatment of the dielectrics, e.g. smoothing the dielectric comprising air gaps
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- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Manufacturing & Machinery (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Internal Circuitry In Semiconductor Integrated Circuit Devices (AREA)
- Exposure And Positioning Against Photoresist Photosensitive Materials (AREA)
Abstract
The application proposes a kind of air bridges manufacturing method, comprising: provides at least two electrodes to be connected of semiconductor substrate and formation on a semiconductor substrate；The first photoresist layer is formed in the substrate and electrode surface, is developed after carrying out Partial exposure to first photoresist layer to first photoresist layer, to form pontic and expose electrode surface；Metal layer and the second photoresist layer are sequentially formed on the electrode and the first photoresist layer, and photoetching is carried out to second photoresist layer, are removed the second photoresist layer on the pontic and electrode, are formed window；Electrodeposition of metals is formed on the metal layer in the window, and removes remaining second photoresist layer；The metal layer unless in the window is removed, first photoresist layer is removed, forms air bridges.The shape of the air bridges manufacturing method that the application is proposed, air bridges can be accurately controlled, and have high aspect ratio and stabilizing mechanical intensity, the yield and repeatability of monolithic integrated microwave circuit manufacturing process can be improved.
Description
Technical field
The present invention relates to technical field of manufacturing semiconductors, more particularly to a kind of air bridges manufacturing method.
Background technique
There is big forbidden bandwidth, height using silicon carbide SiC, gallium nitride GaN, GaAs GaAs the wide bandgap semiconductor of representative
The good characteristics such as critical field strength, high heat conductance, high carrier saturation rate, heterojunction boundary two-dimensional electron gas height, make it
By the concern of people.Theoretically, the metal Schottky-based field-effect tube MESFET of these materials production, high electron mobility are utilized
The devices such as rate transistor HEMT, heterojunction bipolar transistor HBT have incomparable excellent properties in terms of microwave high power.
Since the nineties in last century, the research and development of the monolithic integrated microwave circuit (MMIC) based on wide bandgap semiconductor are in the whole world
It flourishes.
Due to integrate multiple actively and passively components on monolithic integrated microwave circuit, in order to guarantee the high frequency of circuit
Performance connects the electrode in component frequently with air bridge technology.And the production of air bridges belongs to non-standard semiconductor
Technique brings challenge to cost, yield and the homogeneity of monolithic integrated microwave circuit production.
Summary of the invention
The application proposes a kind of air bridges manufacturing method, comprising:
At least two electrodes to be connected of semiconductor substrate and formation on a semiconductor substrate are provided；
The first photoresist layer is formed in the substrate and electrode surface, after carrying out Partial exposure to first photoresist layer
Develop to first photoresist layer, to form pontic and expose electrode surface；
Metal layer and the second photoresist layer are sequentially formed on the electrode and the first photoresist layer, and to described second
Photoresist layer carries out photoetching, removes the second photoresist layer on the pontic and electrode, forms window；
Electrodeposition of metals is formed on the metal layer in the window, and removes remaining second photoresist layer；
The kind layer unless not formed electrodeposition of metals is removed, first photoresist layer is removed, forms air bridges.
In one embodiment, grayscale mask method or approximate exposure method can be used to the first photoresist layer carry out portion
Divide exposure.
In one embodiment, the grayscale mask method carries out the process packet of Partial exposure to first photoresist layer
It includes:
The required exposure dose at the first photoresist layer different location is designed according to bridge shape；
According to the transmissivity of corresponding position on required exposure dose adjustment exposure mask；
Use exposure mask described in ultraviolet light.
In one embodiment, the approximate exposure method carries out the process packet of Partial exposure to first photoresist layer
It includes:
The shape of pontic is designed, and is fitted the shape of the pontic, the exposure agent of same contour line position using contour
It measures identical；
Pontic shape is divided into n Different Plane region according to contour, wherein n is the item number of contour；
The n plane domain is successively exposed using n mask, the transparent region of each exposure mask respectively corresponds one
A plane domain.
In one embodiment, the metal layer is the lamination comprising two or more metals any in titanium, gold and copper.
In one embodiment, the metal in the metal layer is copper, nickel, gold, any combination in palladium.
In one embodiment, remaining second photoresist is removed using flood exposure method or oxygen plasma incineration method
Layer.
In one embodiment, the process that the flood exposure method removes remaining second photoresist layer includes: in no exposure mask
In the case where, use the second photoresist layer described in ultraviolet light；Second photoresist layer immersion is removed in a developer.
In one embodiment, the oxygen plasma incineration method removes the process of remaining second photoresist layer and includes:
Second photoresist layer is placed in completely burned in oxygen plasma environment.
The air bridges manufacturing method that the application is proposed can produce the air bridges of any curvature according to actual needs,
The shape of air bridges can be accurately controlled, and can be produced the air bridges of high aspect ratio and stabilizing mechanical intensity, be improved list
The reliability and stability of piece microwave integrated circuit manufacture craft.
Detailed description of the invention
Fig. 1 is semiconductor structure manufacturing method flow chart provided by one embodiment；
Fig. 2-Fig. 9 is the schematic diagram for indicating the air bridges of manufacture one embodiment；
Figure 10 is the grayscale mask method design drawing for realizing the air bridge structure of one embodiment；
Figure 11 is the approximate exposure method design drawing for realizing the air bridge structure of one embodiment.
Specific embodiment
Air bridges manufacturing method, which is described in further detail, to be proposed to the present invention below in conjunction with the drawings and specific embodiments.Root
According to following explanation and claims, advantages and features of the invention will be become apparent from.It should be noted that attached drawing be all made of it is very simple
The form of change and use non-accurate ratio, only for the purpose of facilitating and clarifying the purpose of the embodiments of the invention.
Please refer to Fig. 1-Fig. 9, the air bridges manufacturing method that the present embodiment is proposed, comprising:
S10: at least two electrodes to be connected of semiconductor substrate and formation on a semiconductor substrate are provided.
Specifically, referring to FIG. 2, including semiconductor substrate 10 and the first electrode 11 and second on the semiconductor
Electrode 12.The semiconductor substrate 10 can be the semiconductor crystal wafers such as gallium nitride, GaAs, silicon carbide, indium phosphide, silicon and table
The epitaxial structure in face.The first electrode 11 and second electrode 12 can be any active or passive device metal electricity
Pole, such as the source electrode of field-effect tube, grid, drain electrode；The battery plate up and down of capacitor element；The lead electrode of inductance component waits.Institute
The composition for stating metal electrode can be any one or more combination and its conjunction in the materials such as titanium, aluminium, nickel, gold, tungsten, titanium nitride
Gold.In the present embodiment, it needs to be attached using air bridges between the first electrode 11 and second electrode 12, illustrate in Fig. 2
Property show three electrodes, appoint it will be appreciated by persons skilled in the art that the first electrode and second electrode can be
It anticipates two electrodes.In other embodiments, the quantity of the electrode can be the arbitrary integer greater than 2.
S20: the first photoresist layer is formed in the substrate and electrode surface, part exposure is carried out to first photoresist layer
Develop after light to first photoresist layer, to form pontic and expose electrode surface.
Wherein, as shown in figure 3, making in one layer photoresist of the substrate 10 and electrode (including all electrodes) surface spin coating
Substrate and electrode described in photoresist overlay form the first photoresist layer 14.First photoresist layer 14 is i-line type positive photoresist,
Thickness is greater than 10um, can so make to be subsequently formed air bridges and has higher aspect ratio.The formation of first photoresist layer 14
Later, Partial exposure is carried out to first photoresist layer 14.Photolithographic exposure of first photoresist layer 14 in different zones
Dosage is inversely proportional with remaining photoresist thickness after development herein, i.e. remaining light is wanted in a certain position of first photoresist layer 14
Photoresist thickness is thicker, then the dosage of position exposure is smaller.After the Partial exposure, first photoresist layer is shown
Shadow removes part photoresist, exposes the surface of the first electrode 11 and second electrode 12, and make 14 shape of the first photoresist layer
At crossstructure 15, the pontic 15 can be the arc of any curvature, such as asymmetric circular arc or symmetrical circular arc.Institute
The shape for stating pontic 15 can be pre-set by the condition of control section exposure.In the present embodiment, the pontic 15 is
Dissymmetrical structure shown in Fig. 4.The pontic 15 is between the first electrode and second electrode, in addition to pontic 15, institute
State the outside of first electrode 11 and second electrode 12 also the first photoresist layer of remainder 14, the thickness of the photoresist of this some residual
Degree is smaller, in order to the uniform spin coating of second of optical cement.The heat treatment temperature of the first time photo-etching technological process is greater than 100C.
S30: metal layer and the second photoresist layer are sequentially formed on the electrode and the first photoresist layer, and to described
Second photoresist layer carries out photoetching, removes the second photoresist layer on the pontic and electrode, forms window.
Specifically, metal layer 17 can be formed on entire chip using the method for metal sputtering, make the metal kind
17 covering of the layer first electrode 11,14 surface of second electrode 12 and the first photoresist layer.The metal layer 17 can for titanium,
The lamination of two or more any metals in the metals such as gold, copper, thickness are no more than 100nm.After the metal layer 17 is formed, then
The second photoresist layer of spin coating 18 on the metal layer 17 makes second photoresist layer 18 cover 17 table of metal layer
Face forms structure shown in fig. 5.Second photoresist layer 18 can be positive photoresist, with a thickness of about 1 micron -2 microns.Then
Second of photoetching is carried out to second photoresist layer 18, the pontic 15 and electrode (including first electrode 11 are removed after development
With second electrode 12) on the second photoresist layer, formed window 19, expose the metal layer 17 in the window 19, formed
Structure as shown in FIG. 6.The heat treatment temperature of second of photoetching process is slightly below the temperature of first time photoetching.
S40: forming electrodeposition of metals on the metal layer in the window, and removes remaining second photoresist layer.
Specifically, as shown in fig. 7, electroplating technology can be used metal deposit to the metal layer 17 in the window 19
On, form electrodeposition of metals 20.The metal can be the combination of metal any in copper, nickel, gold, copper, palladium.It is needed when plating
Metal plate is used to do anode, wafer to be plated does cathode, is immersed in the faintly acid electroplate liquid of particular arrangement and is electroplated
Technique.The parameters such as precise control of temperature, electric current, liquid flow direction, field distribution are needed when plating, to guarantee the uniform of electroplating technology
Property and low stress.The thickness of the electrodeposition of metals 20 is greater than 0.5 micron.After the metal layer 20 is formed, need to remove residue
The second photoresist layer 18, form structure as shown in Figure 8.When removing second photoresist layer 18, the first light cannot be influenced
Photoresist layer 14.For this purpose, ultraviolet light can be used to the second photoresist layer 18 by the way of pan-exposure, in the case where no exposure mask
Exposure is then removed in a developer being completely dissolved.Also the mode that oxygen plasma burning can be used, by the second light
Photoresist layer 18 is reacted with oxygen plasma, in the lower completely burned of the environment of low temperature.No matter first way or the second way,
First photoresist layer 14 is intact due to the protection of metal layer 20.The second photoresist layer of the electroplating technology and removal
Technique is routine techniques, is no longer described in detail herein.
S50: going unless metal layer in the window, removes first photoresist layer, forms air bridges.
The metal layer 17 in the non-window is removed specifically, entire chip can be immersed in wet etchant,
The wet etchant can be any one in the solution such as KI, HF.Since metal layer 17 is compared with electrodeposition of metals 20
Relatively thin, therefore, influence of the wet etching for electroplated layer 20 is not obvious.Later, using organic solvent by remaining first photoetching
Glue-line 14 dissolves, and removes first photoresist layer 14, forms air bridge structure as shown in Figure 9.Finally reuse deionization
The surface for the method cleaning chip that water rinses and oxygen plasma burns.The first photoresist layer of the removal metal layer and removal
Concrete technology is the state of the art, is no longer specifically addressed herein.
It, can be using grayscale mask method or approximate exposure method accurately to control the dosage that Partial exposure is stated in residence.Using
When grayscale mask method, the different parts in exposure mask have a different transmissivities, after exposure mask described in the ultraviolet light of single light intensity,
It is transmitted on first photoresist layer, makes to form scheduled exposure dose distribution on the first photoresist layer.Figure 10 shows one
Kind forms the grayscale mask design of crossstructure shown in Fig. 3, wherein ordinate indicates to penetrate the uv agent amount of exposure mask, horizontal
Coordinate representation different position needs to design the local transmissivity of adjustment corresponding position exposure mask according to this when making exposure mask.Using
It when approximate exposure method, is distributed using step function come approximate dosage, or perhaps is distributed using contour to be fitted the sky of pontic
Between shape.Figure 11 shows a kind of approximate exposure design for forming crossstructure shown in Fig. 3, and wherein abscissa indicates different
Position, ordinate indicate exposure dose.In the present embodiment, first photoresist layer is divided by 7 plane areas according to bridge shape
Domain, 7 exposure masks for then designing different transparent regions are successively exposed.The position exposed every time according to the design in Figure 11,
The exposure dose of the same single exposure in the identical position of contour, same contour line position is identical.Number 1 indicates to expose for the first time.
Number 2 indicates second of exposure, and so on, number 7 indicates the 7th exposure.Exposure dose from high to low, forms approximate arc
The spatial form of pontic.Those skilled in the art can be obtained with reasoning, and plane domain division is smaller, and exposure frequency is more,
Then the pattern of post-develop photoresist is closer to the pontic of design, therefore the plane domain divides, and the agent exposed every time
Amount can be designed according to actual needs.
In conclusion the air bridges manufacturing method that the application is proposed, can produce any curvature according to actual needs
Air bridges, the shape of air bridges can be accurately controlled, and have high aspect ratio and stabilizing mechanical intensity, improve air bridges work
The stability and repeatability of skill.
Each technical characteristic of embodiment described above can be combined arbitrarily, for simplicity of description, not to above-mentioned reality
It applies all possible combination of each technical characteristic in example to be all described, as long as however, the combination of these technical characteristics is not deposited
In contradiction, all should be considered as described in this specification.
The embodiments described above only express several embodiments of the present invention, and the description thereof is more specific and detailed, but simultaneously
It cannot therefore be construed as limiting the scope of the patent.It should be pointed out that coming for those of ordinary skill in the art
It says, without departing from the inventive concept of the premise, various modifications and improvements can be made, these belong to protection of the invention
Range.Therefore, the scope of protection of the patent of the invention shall be subject to the appended claims.
Claims (9)
1. a kind of air bridges manufacturing method characterized by comprising
At least two electrodes to be connected of semiconductor substrate and formation on a semiconductor substrate are provided；
The first photoresist layer is formed in the substrate and electrode surface, first photoresist layer is carried out after Partial exposure to institute
It states the first photoresist layer to develop, to form pontic and expose electrode surface；
Metal layer and the second photoresist layer are sequentially formed on the electrode and the first photoresist layer, and to second photoetching
Glue-line carries out photoetching, removes the second photoresist layer on the pontic and electrode, forms window；
Electrodeposition of metals is formed on the metal layer in the window, and removes remaining second photoresist layer；
The metal layer unless in the window is removed, first photoresist layer is removed, forms air bridges.
2. air bridges manufacturing method according to claim 1, which is characterized in that using grayscale mask method or approximate exposure
Method carries out Partial exposure to first photoresist layer.
3. air bridges manufacturing method according to claim 2, which is characterized in that the grayscale mask method is to first light
Photoresist layer carry out Partial exposure process include:
The shape of pontic is designed, and calculates the exposure dose of the first photoresist layer different location；
Transmissivity of the exposure mask at the corresponding position of first photoresist layer is adjusted according to calculated result；
Use exposure mask described in ultraviolet light.
4. air bridges manufacturing method according to claim 2, which is characterized in that the approximation exposure method is to first light
Photoresist layer carry out Partial exposure process include:
The shape of pontic is designed, and is fitted the shape of the pontic, the exposure dose phase of same contour line position using contour
Together；
First photoresist layer is divided into n Different Plane region, wherein n is the item number of contour.
The n plane domain is successively exposed using n mask, the transparent region of each exposure mask respectively corresponds an institute
State plane domain.
5. air bridges manufacturing method according to claim 1, which is characterized in that the metal layer is to include titanium, Jin He
The lamination of two or more any metals in copper.
6. air bridges manufacturing method according to claim 1, which is characterized in that metal in the metal layer be copper, gold,
Any combination in nickel, palladium.
7. air bridges manufacturing method according to claim 1, which is characterized in that use pan-exposure method or oxygen plasma
Incineration method removes remaining second photoresist layer.
8. air bridges manufacturing method according to claim 7, which is characterized in that the pan-exposure method removes remaining second light
The process of photoresist layer includes: to use the second photoresist layer described in ultraviolet light in the case where no exposure mask；By second light
The immersion of photoresist layer removes in a developer.
9. air bridges manufacturing method according to claim 7, which is characterized in that the oxygen plasma incineration method removal is surplus
The process of the second remaining photoresist layer includes: that second photoresist layer is placed in completely burned in oxygen plasma environment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811337306.0A CN109473391A (en) | 2018-11-12 | 2018-11-12 | Air bridges manufacturing method |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811337306.0A CN109473391A (en) | 2018-11-12 | 2018-11-12 | Air bridges manufacturing method |
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| CN201811337306.0A Pending CN109473391A (en) | 2018-11-12 | 2018-11-12 | Air bridges manufacturing method |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114200789A (en) * | 2022-01-07 | 2022-03-18 | 南京大学 | Air bridge preparation method based on gradient exposure |
| CN115700217A (en) * | 2021-07-21 | 2023-02-07 | 合肥本源量子计算科技有限责任公司 | Preparation method of air bridge and superconducting quantum device |
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| US5136205A (en) * | 1991-03-26 | 1992-08-04 | Hughes Aircraft Company | Microelectronic field emission device with air bridge anode |
| US5723235A (en) * | 1993-11-08 | 1998-03-03 | Sony Corporation | Method of producing photomask and exposing |
| US20070196747A1 (en) * | 2006-02-21 | 2007-08-23 | Yuri Granik | Grid-based resist simulation |
| CN101097860A (en) * | 2007-06-28 | 2008-01-02 | 西安电子科技大学 | Method for producing air bridge of compound semiconductor microwave high power device |
| CN104282844A (en) * | 2013-07-08 | 2015-01-14 | 上海和辉光电有限公司 | Organic light emitting structure, manufacturing method thereof and organic light emitting assembly |
| CN106024702A (en) * | 2016-06-21 | 2016-10-12 | 中山德华芯片技术有限公司 | Manufacturing method of air bridge with inverted trapezoidal pier |
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2018
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5136205A (en) * | 1991-03-26 | 1992-08-04 | Hughes Aircraft Company | Microelectronic field emission device with air bridge anode |
| US5723235A (en) * | 1993-11-08 | 1998-03-03 | Sony Corporation | Method of producing photomask and exposing |
| US20070196747A1 (en) * | 2006-02-21 | 2007-08-23 | Yuri Granik | Grid-based resist simulation |
| CN101097860A (en) * | 2007-06-28 | 2008-01-02 | 西安电子科技大学 | Method for producing air bridge of compound semiconductor microwave high power device |
| CN104282844A (en) * | 2013-07-08 | 2015-01-14 | 上海和辉光电有限公司 | Organic light emitting structure, manufacturing method thereof and organic light emitting assembly |
| CN106024702A (en) * | 2016-06-21 | 2016-10-12 | 中山德华芯片技术有限公司 | Manufacturing method of air bridge with inverted trapezoidal pier |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115700217A (en) * | 2021-07-21 | 2023-02-07 | 合肥本源量子计算科技有限责任公司 | Preparation method of air bridge and superconducting quantum device |
| CN114200789A (en) * | 2022-01-07 | 2022-03-18 | 南京大学 | Air bridge preparation method based on gradient exposure |
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Application publication date: 20190315 |