JP2002080804A - Adhesive film for grinding rear surface of semiconductor wafer and process for grinding rear surface of semiconductor wafer using this - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive film for grinding the rear surfaces of semiconductor wafers having an excellent adhesion to wafer surfaces and a low stainability. SOLUTION: The adhesive film for grinding rear surfaces of semiconductor wafers has an adhesive layer formed from an adhesive containing 100 pts.wt. acrylic adhesive polymer prepared through emulsion polymerization and from 0.1 to 15 pts.wt. crosslinking agent having two or more functional groups within a molecule. Here, the acrylic adhesive polymer contains from 10 to 98.9 wt.% alkyl (meth)acrylate main monomer unit (A), from 1 to 40 wt.% monomer unit (B) having a functional group reactive with the crosslinking agent and from 0.1 to 30 wt.% bifunctional monomer unit (C) containing a di(meth)acrylate unit having from 1 to 100 alkylene oxide units.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive film for grinding the back surface of a semiconductor wafer (hereinafter referred to as "adhesive film") and a method for grinding the back surface of a semiconductor wafer using the same. More specifically, the adhesive film is attached to a surface of a semiconductor wafer such as a silicon wafer on which the integrated circuit is incorporated (hereinafter, wafer surface), and the other surface of the wafer (hereinafter, wafer back surface)
The present invention relates to a method of grinding a back surface of a semiconductor wafer, which is useful for preventing damage to a semiconductor wafer, and the like, and an adhesive film for grinding a back surface of a semiconductor wafer used in the method.

[0002]

2. Description of the Related Art Normally, a semiconductor integrated circuit is manufactured by slicing a high-purity silicon single crystal or the like into a wafer, incorporating the integrated circuit by ion implantation, etching, or the like, and further grinding, polishing, or lapping the back surface of the wafer. It is manufactured by grinding and reducing the thickness of the wafer to about 100 to 600 μm, and then dicing to make chips. In these processes, an adhesive film for grinding the back surface of the semiconductor wafer is adhered to the wafer surface through the adhesive layer to prevent breakage of the semiconductor wafer when grinding the back surface of the wafer and to facilitate the grinding process. Protection methods are used. Specifically, an adhesive film for grinding the back surface of a semiconductor wafer is directly adhered to the wafer surface via the adhesive layer to protect the wafer surface, and then the back surface of the wafer is ground. After the grinding is completed, the adhesive film is peeled off from the wafer surface.

A conventional adhesive film for grinding the back surface of a semiconductor wafer is used to grind the back surface of a semiconductor wafer in which integrated circuits are built up to the periphery of the wafer, that is, a scribe line reaches the outermost periphery of the wafer. In the case where the wafer is used, water enters between the wafer surface and the adhesive layer through the concave portion based on the scribe line, thereby damaging the wafer or causing grinding debris to enter with the water and contaminate the wafer surface. There was something. In order to prevent these problems, measures have been taken to increase the thickness of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive film and improve the adhesion between the concave portion on the wafer surface and the pressure-sensitive adhesive layer. However, when using this method,
The adhesive force of the adhesive film to the wafer surface becomes greater than the strength of the wafer, and depending on various conditions such as the thickness and surface shape of the wafer, when the adhesive film is peeled off from the wafer surface after grinding the back surface, it is peeled off by an automatic peeling machine. In some cases, a trouble occurred or the wafer was destroyed.

As a means for solving such a problem, for example, Japanese Patent Application Laid-Open No. 60-189938 discloses a method of grinding a back surface of a semiconductor wafer, attaching a pressure-sensitive adhesive film to the wafer surface, and grinding the back surface. In a method for protecting a semiconductor wafer in which an adhesive film is peeled off, the pressure-sensitive adhesive film has a property of being cured by light irradiation on a light-transmissive support and light provided on the support, thereby forming a three-dimensional network. A method for protecting a semiconductor wafer, comprising an adhesive layer and irradiating the adhesive film with light after the grinding and before peeling the adhesive film, is disclosed.

In the method of protecting a semiconductor wafer disclosed in the above invention, the adhesive force of the adhesive film to the wafer surface can be reduced by irradiating light before peeling. Thus, the adhesion to the wafer surface at the time of grinding the back surface can be sufficiently increased without taking into account the above, and the problem of intrusion of water and grinding debris between the wafer surface and the adhesive layer can be solved.

However, when this adhesive film is used, it is necessary to irradiate light after grinding the back surface until the adhesive film is separated from the wafer surface.
It is necessary to introduce light irradiation equipment during the process, and there has been a problem that the device becomes large-sized and complicated, and the process becomes complicated and the workability is reduced. It has also been pointed out that the working environment is deteriorated by ozone generated by light irradiation.
Furthermore, depending on various conditions such as the surface shape of the wafer, the light irradiation intensity, and the time, a problem of adhesive residue may occur on the wafer surface after peeling due to poor curing of the pressure-sensitive adhesive layer. In order to prevent such a problem, it is necessary to fill the inside of the light irradiation device with an inert gas such as nitrogen, which increases the manufacturing cost and further increases the size and complexity of the process. .

[0007] In order to solve these problems, the present inventors disclosed in a patent application relating to Japanese Patent Application Laid-Open No. 11-315259, a pressure-sensitive adhesive layer containing a specific alkylene glycol-based polymer as an essential component. The present invention has proposed a protective adhesive film for a semiconductor wafer, which has a feature.
The protective adhesive film for a semiconductor wafer disclosed in the invention, when grinding the back surface of the semiconductor wafer, breakage of the wafer and wafer surface due to water and grinding debris infiltrating between the wafer surface and the adhesive layer No contamination of
Since the adhesive force is in an appropriate range, the wafer is not damaged when the adhesive film is peeled off from the wafer, and it is not necessary to newly introduce equipment such as a light irradiation device into the process. Further, there is described a feature that no adhesive residue occurs after the adhesive film is peeled off from the wafer, so that the surface of the semiconductor wafer is not contaminated.

However, in recent years, as the semiconductor industry demands technological innovation and cost reduction, semiconductor wafers are becoming larger and larger year by year.
It tends to be thin. In particular, as the demand for thinner semiconductor chips, such as thinner packaging and smart card applications, is increasing, the thickness of semiconductor wafers after back grinding is becoming thinner. is there. Since the time required for the back surface grinding increases with the area of the wafer, the problem of breakage and contamination of the wafer due to the intrusion of water and grinding chips during the grinding is considered to occur more easily as the size of the wafer increases. Furthermore, considering that the strength of the wafer itself decreases as the thickness of the wafer decreases, the problem of the wafer being damaged at the time of peeling described above will become more and more serious with the thinning of the wafer. is expected.

In addition, with the recent trend toward smaller and lighter semiconductor devices, the diversification of the semiconductor wafer surface has been rapidly progressing.
Wafers having a surface shape in which a part of an adhesive for CPUs, flash memories, smart cards, and the like are likely to remain are increasing. For example, a wafer having chips suitable for smart card applications has a height of 5 to 300
Wafers having μm protruding high bump electrodes are being produced. When grinding the back surface of a semiconductor wafer having a protruding high bump electrode on the surface as described above, when the adhesive film is peeled from the ground wafer, a part of the adhesive remains on the surface of the wafer, and the wafer The surface could be contaminated. Contamination due to this adhesive residue
In particular, it often occurs around the high bump electrodes, and in such a case, it is difficult to remove contamination even by post-processing such as cleaning, which may cause a particularly serious problem.

[0010] Under such circumstances, conventionally, the adhesive film for grinding the back surface of the semiconductor wafer has a good contact with the concave portion of the wafer surface during the back surface grinding, and water permeates between the wafer surface and the adhesive layer. It is required that the wafer surface is not damaged by polishing and the polishing debris does not enter and cause contamination of the wafer surface, that the wafer surface can be peeled with an appropriate adhesive force at the time of peeling, and that the wafer surface is not contaminated after peeling. . However, their required levels have become increasingly severe in recent years and are expected to become even more severe in the future. Therefore, there is a demand for an adhesive film for grinding the back surface of a semiconductor wafer, which can respond to the above requirements at a higher level.

[0011]

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to withstand the stress when grinding the back surface of a wafer,
Provided is an adhesive film for grinding the back surface of a semiconductor wafer, which has an appropriate adhesive force that does not damage the wafer at the time of peeling, and has excellent adhesion to the wafer surface and low contamination, and a method for grinding the back surface of a semiconductor wafer using the same. Is to do.

[0012]

DISCLOSURE OF THE INVENTION In view of the problem of contamination, the present inventors aimed at increasing the molecular weight of an acrylic pressure-sensitive adhesive polymer in order to maintain a high cohesive force of the acrylic pressure-sensitive adhesive polymer. As a result of intensive studies, the acrylic pressure-sensitive adhesive polymer was polymerized by emulsion polymerization, and the acrylic pressure-sensitive adhesive polymer reacted with a specific amount of a (meth) acrylic acid alkyl ester-based main monomer unit (A) and a crosslinking agent. The inventors have found that the above problem can be solved by including a monomer unit (B) having a functional group to be obtained and a bifunctional monomer unit (C) represented by the following general formula (1), and have reached the present invention. .

That is, the present invention relates to an adhesive film for grinding a back surface of a semiconductor wafer, wherein an adhesive layer is provided on one surface of a base film, wherein the adhesive layer comprises an alkyl (meth) acrylate-based main monomer unit. (A) 10 to 98.9% by weight, a monomer unit having a functional group capable of reacting with a crosslinking agent (B) 1 to 40% by weight, and the general formula (1)

[0014]

Embedded image

(In the general formula (1), R ₁ and R ₂ each represent hydrogen or a methyl group. A represents an alkylene oxide unit. The number of ethylene oxide units (n) in A is from 0 to 20; The number of units (m) of the alkylene oxide having 3 to 12 is 1 to 80, and n is 0.
When (n <m), When n is 1 to 20 (n ≦ m)
Which can be either a random copolymer or a block copolymer). Acrylic adhesive prepared by emulsion polymerization containing 0.1 to 30% by weight of a bifunctional monomer unit (C) represented by the following formula: And a pressure-sensitive adhesive containing 0.1 to 15 parts by weight of a crosslinking agent having two or more functional groups in one molecule per 100 parts by weight of the acrylic polymer and the acrylic pressure-sensitive adhesive polymer. It is an adhesive film for grinding the backside of a semiconductor wafer.

Another aspect of the present invention is a method of grinding the back surface of a semiconductor wafer using the adhesive film for grinding the back surface of a semiconductor wafer, wherein the adhesive film is attached to a circuit forming surface of the semiconductor wafer, and the back surface of the semiconductor wafer is ground. A method for grinding a back surface of a semiconductor wafer, comprising grinding and peeling off the adhesive film after finishing the grinding.

The adhesive film for grinding the back surface of a semiconductor wafer according to the present invention is characterized by using an acrylic polymer containing a specific amount of a bifunctional monomer unit represented by the above-mentioned general formula (1) among the above constitutions; In that the polymer is prepared by emulsion copolymerization. The adhesive tape for grinding the backside of a semiconductor wafer having such a feature improves the adhesion between the wafer surface and the adhesive layer when grinding the backside of the semiconductor wafer, and causes water and grinding debris to enter in the backside grinding step. Wafer damage and contamination of the wafer surface do not occur. Further, since the adhesive film has an appropriate adhesive strength, it does not peel off when grinding the back surface of the wafer, and does not break when the adhesive film is peeled off from the wafer. Further, since contamination due to adhesive residue or the like does not occur after the adhesive film is peeled off from the wafer, the surface of the semiconductor wafer is not contaminated.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The present invention relates to an adhesive film for grinding the back surface of a semiconductor wafer in which an adhesive layer is formed on one surface of a base film with an adhesive having a specific composition, and a method for grinding the back surface of a semiconductor wafer using the adhesive film.

The pressure-sensitive adhesive film for grinding the back surface of a semiconductor wafer of the present invention is provided on one surface of a base film or a release film.
Solution or emulsion containing acrylic adhesive polymer, cross-linking agent, and other additives as necessary
These are collectively referred to as a pressure-sensitive adhesive coating solution) and dried to form a pressure-sensitive adhesive layer.

When the pressure-sensitive adhesive coating solution is applied to one surface of the substrate film to form a pressure-sensitive adhesive layer, a release film is applied to the surface of the applied pressure-sensitive adhesive layer in order to protect it from contamination due to the environment. It is preferable to stick. On the other hand, when an adhesive coating solution is applied to one surface of a release film to form an adhesive layer, a method of transferring the adhesive layer to a base film is employed. Which of the base film and the release film is to be coated with the pressure-sensitive adhesive coating solution is determined in consideration of the heat resistance of the base film and the release film and the contamination of the semiconductor wafer surface. For example, when the heat resistance of the release film is superior to that of the base film, it is preferable to provide an adhesive layer on the surface of the release film and then transfer it to the base film. When the heat resistance is the same or the base film is excellent, it is preferable to provide an adhesive layer on the surface of the base film and to adhere a release film to the surface.

However, in consideration of the fact that the adhesive film for grinding the back surface of the semiconductor wafer is adhered to the surface of the semiconductor wafer through the surface of the adhesive layer that is exposed when the release film is peeled off, In order to prevent surface contamination, use a release film with good heat resistance,
A method of applying a pressure-sensitive adhesive coating solution on the surface and drying to form a pressure-sensitive adhesive layer, and transferring this to a substrate film is more preferable. The adhesive film for grinding the backside of a semiconductor wafer according to the present invention,
Usually, a release film is adhered to the surface of the pressure-sensitive adhesive layer and stored in a state where the release film is peeled off when used.

As the base film used in the present invention, a film obtained by molding a synthetic resin into a film is used.
The base film may be a single layer or a laminate. The thickness of the base film is preferably from 10 to 500 μm. More preferably, it is 70 to 500 μm. Examples of the raw material resin for the base film include synthetic resins such as polyethylene, polypropylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-propylene copolymer, polyvinyl chloride, polyamide, and polyethylene terephthalate. Can be

Among these, considering the protection performance of the wafer during backside grinding, the raw material having a Shore D type hardness of 40 or less specified in ASTM-D-2240-86 or JIS K-7215-1986. Resins are particularly preferred. When molding these resins into a film,
If necessary, stabilizers, lubricants, antioxidants, pigments, antiblocking agents, plasticizers and the like may be added. When various additives such as a stabilizer are added when the base film is formed, the additives may transfer to the pressure-sensitive adhesive layer, change the characteristics of the pressure-sensitive adhesive, or contaminate the wafer surface. In such a case, it is preferable to provide a barrier layer between the base film and the pressure-sensitive adhesive layer.

Further, in the case where the surface of the semiconductor wafer is continuously protected by using the adhesive film for grinding the back surface of the semiconductor wafer during the etching process using the etchant performed after the grinding of the back surface of the semiconductor wafer, the chemical resistance is high. It is preferable to use a base film having excellent properties. For example,
For example, a chemical-resistant film such as polypropylene is laminated on the surface of the base film opposite to the side on which the pressure-sensitive adhesive layer is provided.
In order to improve the adhesive strength between the base film and the adhesive layer,
The surface of the base film on which the pressure-sensitive adhesive layer is provided is preferably subjected to corona discharge treatment or chemical treatment in advance. Also,
A primer may be used between the base film and the pressure-sensitive adhesive layer.
The base film used in the present invention is selected from those manufactured by known techniques such as a calendering method, a T-die extrusion method, an inflation method, etc., in consideration of productivity, thickness accuracy of the obtained film, and the like. Can be.

The release film used in the present invention includes:
Synthetic resin films such as polypropylene and polyethylene terephthalate are exemplified. Preferably, the surface thereof is subjected to a silicone treatment or the like as necessary. The thickness of the release film is usually from 10 to 200 μm. Preferably it is 30 to 100 μm.

The pressure-sensitive adhesive coating solution used in the present invention comprises (meth)
Specific amounts of an alkyl acrylate monomer unit (A), a monomer unit (B) having a functional group capable of reacting with a crosslinking agent, and a bifunctional monomer unit (C) represented by the general formula (1) are included. A solution or emulsion solution containing an acrylic pressure-sensitive adhesive polymer of an emulsion polymerization copolymer, and a crosslinker having two or more functional groups in one molecule for increasing cohesive force or adjusting pressure-sensitive adhesive force. When used in a solution, the acrylic pressure-sensitive adhesive polymer is separated from the emulsion obtained by emulsion polymerization by salting out and then redissolved in a solvent or the like. Has a sufficiently high molecular weight, has low solubility in a solvent, or does not dissolve in many cases. From the viewpoint of cost, it is preferable to use the emulsion as it is.

The acrylic pressure-sensitive adhesive polymer used in the present invention comprises an alkyl acrylate, an alkyl methacrylate, or a mixture thereof as a main monomer [hereinafter, referred to as a main monomer.
The monomer (A)] is obtained by copolymerizing a monomer mixture containing a comonomer having a functional group capable of reacting with a crosslinking agent.

The monomer (A) has 1 to 12 carbon atoms.
Alkyl acrylate or methacrylic acid alkyl ester having a degree of alkyl group [hereinafter, these are collectively referred to as (meth) acrylic acid alkyl ester]
Is mentioned. Preferably, it is an alkyl (meth) acrylate having an alkyl group having 1 to 8 carbon atoms.
Specifically, methyl acrylate, methyl methacrylate,
Examples include ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, and 2-ethylhexyl acrylate. These may be used alone or as a mixture of two or more. It is preferable that the amount of the monomer (A) used is usually contained in the range of 10 to 98.9% by weight in the total amount of all the monomers used as the raw material of the pressure-sensitive adhesive polymer. More preferably, it is 85 to 95% by weight. By setting the amount of the monomer (A) to be in the above range, 10 to 98.9% by weight, preferably 85% by weight of the alkyl (meth) acrylate monomer unit (A).
A polymer containing を 95% by weight is obtained.

Examples of the monomer (B) forming a monomer unit (B) having a functional group capable of reacting with a crosslinking agent include acrylic acid, methacrylic acid, itaconic acid, mesaconic acid, citraconic acid, fumaric acid, maleic acid and itaconic acid. Acid monoalkyl ester, mesaconic acid monoalkyl ester, citraconic acid monoalkyl ester, fumaric acid monoalkyl ester, maleic acid monoalkyl ester, acrylic acid-2-hydroxyethyl, methacrylic acid-2-hydroxyethyl, acrylamide, methacrylamide, Examples include tert-butylaminoethyl acrylate and tert-butylaminoethyl methacrylate.
Preferably, acrylic acid, methacrylic acid, acrylic acid-
2-hydroxyethyl, 2-hydroxyethyl methacrylate, acrylamide, methacrylamide and the like.
One of these may be copolymerized with the above main monomer, or two or more thereof may be copolymerized. The amount of the monomer (B) having a functional group capable of reacting with the cross-linking agent is usually in the total amount of all the monomers used as the raw material of the pressure-sensitive adhesive polymer.
It is preferably contained in the range of 1 to 40% by weight.
More preferably, it is 1 to 10% by weight. Thus, a polymer having a constitutional unit (B) having a composition substantially equal to the monomer composition is obtained.

In the present invention, attention has been paid to the bulk properties of emulsion particles as a measure for developing adhesion without depending on additives and the like. For emulsion particles,
The cohesive force is maintained by copolymerizing a bifunctional monomer having a relatively long structure between the crosslinking points and a flexible structure,
The emphasis was on improving the crosslinking system to improve the adhesive properties. As a result, a bifunctional monomer (C) represented by the above general formula (1) was selected as a monomer that copolymerizes well. By copolymerizing a specific bifunctional monomer (C) with the acrylic pressure-sensitive adhesive polymer, the adhesion between the pressure-sensitive adhesive layer and the wafer surface is improved, and between the wafer surface and the pressure-sensitive adhesive layer when grinding the back surface of the wafer. Has the effect of preventing water from penetrating into the wafer (hereinafter referred to as water resistance), does not cause breakage of the wafer when the adhesive film is peeled off from the wafer surface, and has a wafer surface (especially having a high bump electrode) caused by the adhesive layer. In the case of a wafer, no contamination occurs around the high bump electrode).

The alkylene oxide unit (m + n) of A in the structural formula of the bifunctional monomer unit (C) represented by the general formula (1) is preferably as long as possible. More preferably, in the general formula (1), the number of ethylene oxide units (n) is (0 ≦ n ≦ 20), and the number of units of alkylene oxide having 3 to 12 carbon atoms (m) is (1 ≦ m ≦ 80). In the case where the bifunctional monomer (C) represented by the general formula (1) is emulsion-copolymerized, a large amount of aggregates may be generated during the polymerization reaction or a cross-linking reaction may not easily occur depending on the type of the monomer. is there. Considering this point, when n is 0, (n <
m) and n is preferably 1 to 20 (n ≦ m).

The amount of the bifunctional monomer (C) represented by the general formula (1) affects the stability during emulsion polymerization. If the amount is too large, the polymerization stability tends to decrease. From such a viewpoint, the amount of the bifunctional monomer represented by the general formula (1) is 0.1 to 30% by weight in all the monomers.
It is preferred to include. More preferably 0.1 to 5% by weight
It is. Thus, a polymer having a constitutional unit (C) having a composition substantially equal to the monomer composition is obtained.

Examples of such a bifunctional monomer include:
For example, both ends are diacrylate or dimethacrylate and the structure of the main chain is a propylene glycol type [manufactured by NOF CORPORATION, trade name; PDP-200 (n = 0, m =
4), PDP-400 (n = 0, m = 9), ADP
-200 (n = 0, m = 4) and ADP-400 (n =
0, m = 9)], tetramethylene glycol type [manufactured by NOF CORPORATION, trade name; ADT-250 (n = 0, m =
3), ADT-850 (n = 0, m = 12)] and a mixed type thereof (trade name: ADET-, manufactured by NOF Corporation)
1800 (n = 15.5, m = 15.5), ADPT
-4000 (n = 0, m = 60)].

In the present invention, in addition to the main monomer constituting the pressure-sensitive adhesive polymer and the comonomer having a functional group capable of reacting with the crosslinking agent, a specific comonomer having properties as a surfactant (hereinafter referred to as polymerizable surfactant) Agent)
May be copolymerized. The polymerizable surfactant has a property of copolymerizing with the main monomer and the comonomer, and also has an action as an emulsifier in the case of emulsion polymerization. When an acrylic pressure-sensitive adhesive polymer emulsion-polymerized with a polymerizable surfactant is used, the surface of the wafer is not normally contaminated by the surfactant. In addition, even when slight contamination due to the pressure-sensitive adhesive layer occurs, it can be easily removed by washing the wafer surface with water.

Examples of such a polymerizable surfactant include, for example, those obtained by introducing a polymerizable 1-propenyl group into a benzene ring of polyoxyethylene nonyl phenyl ether [Daiichi Kogyo Seiyaku Co., Ltd .; Name: Aqualon RN
-10, RN-20, RN-30, RN-50
Etc.), which is polymerizable on the benzene ring of ammonium salt of polyoxyethylene nonylphenyl ether sulfate.
-With a propenyl group introduced [Daiichi Kogyo Seiyaku Co., Ltd.
Product name: AQUALON HS-10, HS-20
And the like, and a sulfosuccinic acid diester having a polymerizable double bond in the molecule [manufactured by Kao Corporation; trade name: Latemul S
-120A, S-180A and the like]. Further, if necessary, a monomer having a polymerizable double bond such as vinyl acetate, acrylonitrile, and styrene may be copolymerized.

Examples of the polymerization reaction mechanism of the acrylic pressure-sensitive adhesive polymer include radical polymerization, anionic polymerization, and cationic polymerization. In consideration of the production cost of the pressure-sensitive adhesive, the influence of the functional group of the monomer, the influence of ions on the surface of the semiconductor wafer, and the like, it is preferable to perform polymerization by radical polymerization. When polymerizing by a radical polymerization reaction, organic radicals such as benzoyl peroxide, acetyl peroxide, isobutyryl peroxide, octanoyl peroxide, di-tert-butyl peroxide, di-tert-amyl peroxide are used as radical polymerization initiators. Peroxide, ammonium persulfate, potassium persulfate,
Inorganic peroxides such as sodium persulfate, 2,2'-azobisisobutyronitrile, 2,2'-azobis-2-methylbutyronitrile, 4,4'-azobis-4-cyanovaleric acid, etc. Of the azo compound.

When the polymerization is carried out by the emulsion polymerization method, among these radical polymerization initiators, inorganic peroxides such as water-soluble ammonium persulfate, potassium persulfate and sodium persulfate; An azo compound having a carboxyl group in the molecule, such as' -azobis-4-cyanovaleric acid, is preferred. Considering the effect of ions on the semiconductor wafer surface, ammonium persulfate, 4,4 '
An azo compound having a carboxyl group in the molecule, such as -azobis-4-cyanovaleric acid, is more preferred.
An azo compound having a carboxyl group in the molecule, such as 4,4'-azobis-4-cyanovaleric acid, is particularly preferred.

The cross-linking agent having two or more cross-linkable functional groups in one molecule used in the present invention is used to react with the functional group of the acrylic pressure-sensitive adhesive polymer to adjust the adhesion and cohesion. Examples of the crosslinking agent include epoxy compounds such as sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, glycerol polyglycidyl ether, neopentyl glycol diglycidyl ether, and resorcin diglycidyl ether. , Tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate triadduct of trimethylolpropane, isocyanate compounds such as polyisocyanate, trimethylolpropane-tri-β-aziridinylpropionate, tetramethylolmethane-tri-β- Aziridinyl propionate, N, N'-diphenylmethane-4,
4'-bis (1-aziridinecarboxamide), N,
N'-hexamethylene-1,6-bis (1-aziridinecarboxamide), N, N'-toluene-2,4-bis (1-aziridinecarboxamide), trimethylolpropane-tri-β- (2- Aziridine compounds such as methylaziridine) propionate; and melamine compounds such as hexamethoxymethylolmelamine. These may be used alone or in combination of two or more.

The content of the cross-linking agent is usually within such a range that the number of functional groups in the cross-linking agent does not become larger than the number of functional groups in the acrylic pressure-sensitive adhesive polymer. However, when a new functional group is generated by the crosslinking reaction, or when the crosslinking reaction is slow, it may be contained in excess as necessary. The preferred content is
The crosslinking agent is 0.1 to 15 parts by weight based on 100 parts by weight of the acrylic pressure-sensitive adhesive polymer. When the content is small, the cohesive force of the pressure-sensitive adhesive layer becomes insufficient, and adhesive residue due to the pressure-sensitive adhesive layer easily occurs on the wafer surface (especially, in the case of a wafer having a high bump electrode, around the high bump electrode). In addition, the adhesive strength may be increased outside the range of the present invention, and when the adhesive film is peeled from the wafer surface, a peeling trouble may occur in an automatic peeling machine, or the wafer may be completely damaged. If the content is high, the adhesion between the pressure-sensitive adhesive layer and the wafer surface is weakened, and water or grinding debris may enter during grinding, damaging the wafer, or causing contamination of the wafer surface by the grinding debris. is there.

The pressure-sensitive adhesive coating liquid used in the present invention includes an acrylic pressure-sensitive adhesive polymer obtained by copolymerizing the above-mentioned specific bifunctional monomer, a crosslinking agent, a rosin-based resin, a terpene resin-based resin, etc. May be appropriately contained to such an extent that the object of the present invention is not affected. When the coating liquid is an emulsion liquid, a film-forming auxiliary such as diethylene glycol monoalkyl ether may be appropriately added to such an extent that the object of the present invention is not affected. Considering that diethylene glycol monoalkyl ether and its derivatives used as a film-forming aid may cause contamination of the wafer surface to such an extent that cleaning becomes impossible when contained in a large amount in the adhesive layer. It is preferable to use a substance that volatilizes at the temperature at the time of drying after the application of the pressure-sensitive adhesive, and to reduce the amount remaining in the pressure-sensitive adhesive layer.

The thickness of the pressure-sensitive adhesive layer is 3 to 100 μm.
The preferred thickness is 5 to 80 μm. When the thickness of the pressure-sensitive adhesive layer is reduced, water resistance is inferior, water enters between the wafer surface and the pressure-sensitive adhesive layer during back surface grinding, and the wafer is damaged,
The wafer surface tends to be contaminated by grinding dust. When the thickness of the pressure-sensitive adhesive layer is large, it may be difficult to prepare a pressure-sensitive adhesive film, or the productivity may be affected, leading to an increase in manufacturing cost.

The adhesive force of the adhesive film for grinding the back surface of a semiconductor wafer in the present invention can be appropriately adjusted in consideration of the grinding conditions of the wafer surface, the diameter of the wafer, the thickness of the wafer after grinding, etc., but the adhesive force is too low. And it becomes difficult to attach the adhesive film to the wafer surface, or water enters between the wafer surface and the adhesive layer during backside grinding, causing damage to the wafer,
The wafer surface tends to be contaminated by grinding debris and the like. Also, if the adhesive force is too high, when peeling the adhesive film from the wafer surface after the back surface grinding, peeling trouble occurs in the automatic peeling machine, such as peeling workability is reduced,
The wafer may be damaged. Usually SUS30
5 to 500 g / 2 in terms of adhesion to 4-BA plate
5 mm, preferably 10 to 200 g / 25 mm.

As a method for applying the pressure-sensitive adhesive coating solution to one surface of the base film or the release film, a conventionally known coating method, for example, a roll coater method, a reverse roll coater method, a gravure roll method, a bar coat method, a comma coater Method, die coater method or the like can be adopted. The drying condition of the applied pressure-sensitive adhesive is not particularly limited, but generally, 8
It is preferable to dry in a temperature range of 0 to 200 ° C. for 10 seconds to 10 minutes. More preferably, 80 to 170 ° C
For 15 seconds to 5 minutes.

In order to sufficiently promote the crosslinking reaction between the crosslinking agent and the pressure-sensitive adhesive polymer, after the drying of the pressure-sensitive adhesive coating solution is completed, the pressure-sensitive adhesive film for grinding the back surface of the semiconductor wafer is reduced to 40 to 40%.
You may heat at 80 degreeC for about 5-300 hours.

The method for producing the adhesive film for grinding the back surface of a semiconductor wafer in the present invention is as described above. From the viewpoint of preventing contamination of the surface of the semiconductor wafer, all the raw materials such as a base film, a release film and an adhesive base material are used. Material production environment,
The preparation, storage, application and drying environment of the pressure-sensitive adhesive coating solution is preferably maintained at a cleanliness of class 1,000 or less specified by US Federal Standard 209b.

Next, the method for grinding the back surface of a semiconductor wafer according to the present invention will be described. The method for grinding the back surface of a semiconductor wafer according to the present invention is characterized in that when grinding the back surface of the semiconductor wafer, an adhesive film for grinding the back surface of a semiconductor wafer manufactured by the above method is used.

More specifically, first, the release film is peeled off from the adhesive layer of the adhesive film for grinding the back surface of the semiconductor wafer.
The surface of the pressure-sensitive adhesive layer is exposed, and the surface of the pressure-sensitive adhesive layer is adhered to the surface (front surface) of the semiconductor wafer on which the integrated circuit is incorporated through the pressure-sensitive adhesive layer. Next, the semiconductor wafer is fixed to a chuck table or the like of a grinding machine via the base film layer of the adhesive film, and the back surface (the surface on which the integrated circuit is not formed) of the semiconductor wafer is ground. After the grinding is completed, the adhesive film is peeled off. After the grinding of the back surface of the wafer is completed, a chemical etching process may be performed before the adhesive film is peeled off. If necessary, after the adhesive film is peeled off, the surface of the semiconductor wafer is subjected to processing such as water washing and plasma washing.

In such a back-grinding operation, the thickness of the semiconductor wafer before grinding is usually 500 to 1000 μm, while the thickness is usually 1 to 500 μm depending on the type of the semiconductor chip.
It is ground to about 00 to 600 μm. If necessary,
It may be thinner than 100 μm. The thickness of the semiconductor wafer before grinding is appropriately determined according to the diameter and type of the semiconductor wafer, and the thickness of the wafer after grinding is appropriately determined according to the size of the obtained chip, the type of circuit, and the like.

The operation of attaching the adhesive film to the semiconductor wafer may be performed manually, but is generally performed by an apparatus called an automatic attaching machine having a roll-shaped adhesive film attached thereto. As such an automatic pasting machine,
For example, Takatori Co., Ltd., format: ATM-1000B,
ATM-1100, manufactured by Teikoku Seiki Co., Ltd., Model: STL
There are series etc.

As the back grinding method, a known grinding method such as a through feed method and an in-feed method is employed. Each grinding is performed while cooling water by applying water to the semiconductor wafer and the grindstone. After the back surface grinding, chemical etching is performed as needed. Chemical etching adheres to an etching solution selected from the group consisting of an acidic aqueous solution composed of a single or mixed liquid of hydrofluoric acid, nitric acid, sulfuric acid, acetic acid and the like, and an alkaline aqueous solution such as a potassium hydroxide aqueous solution and a sodium hydroxide aqueous solution. This is performed by a method such as immersing the semiconductor wafer with the film adhered.
The etching removes strain generated on the back surface of the semiconductor wafer,
This is performed for the purpose of further reducing the thickness of the wafer, removing an oxide film or the like, performing pretreatment when forming electrodes on the back surface, and the like. The etching solution is appropriately selected according to the above purpose.

After the back surface grinding and chemical etching are completed, the adhesive film is peeled off from the wafer surface. This series of operations may be performed manually, but is generally performed by a device called an automatic peeling machine. Such an automatic peeling machine is manufactured by Takatori Co., Ltd., type: ATR
M-2000B, ATRM-2100, manufactured by Teikoku Seiki Co., Ltd., type: STP series, etc.

The surface of the wafer from which the adhesive film has been peeled off is washed if necessary. Examples of the cleaning method include wet cleaning such as water cleaning and solvent cleaning, and dry cleaning such as plasma cleaning. In the case of wet cleaning, ultrasonic cleaning may be used together. These cleaning methods are appropriately selected depending on the state of contamination on the wafer surface.

The adhesive film for grinding the backside of a semiconductor wafer of the present invention and the semiconductor wafer to which the backside grinding method of the semiconductor wafer using the same can be applied are not limited to silicon wafers, but include germanium, gallium-arsenic, gallium-phosphorus, and the like.
Wafers such as gallium-arsenic-aluminum are exemplified.

[0054]

The present invention will be described below in further detail with reference to examples. In all Examples and Comparative Examples shown below, Class 1 specified in US Federal Standard 209b was used.
Preparation and application of an adhesive coating solution, grinding of the back surface of a semiconductor silicon wafer, and the like were performed in an environment maintained at a clean degree of 000 or less. The present invention is not limited to these examples. The various characteristic values shown in the examples were measured by the following methods.

(1) Adhesive strength (g / 25 mm) Except for the conditions specified below, all are JIS Z-0237.
-Measured according to 1991. Under an atmosphere of 23 ° C., the pressure-sensitive adhesive film obtained in the example or the comparative example was passed through the pressure-sensitive adhesive layer to form a 5 cm × 20 cm SUS304-
It is stuck on the surface of a BA plate (JISG-4305-1991) and left for 60 minutes. One end of the sample was sandwiched, and a peeling angle of 180 ° and a peeling speed of 300 mm / min. With SUS3
The stress at the time of peeling the sample from the surface of the 04-BA plate is measured, and converted to an adhesive force of g / 25 mm.

(2) ESCA Measurement The contamination of the silicon mirror wafer chip surface by ESCA (ESCA-3200 manufactured by Shimadzu) is evaluated. An adhesive film for a sample is bonded to a silicon mirror wafer (diameter: 4 inches, thickness:
Temperature of 23 ± 2 in a state of being adhered to the entire surface of
After standing in an atmosphere adjusted to 50 ° C. and a relative humidity of 50 ± 5% for 60 minutes, the adhesive film was removed from the silicon mirror wafer by a grinder [manufactured by Disco Co., Ltd., type: DFG-82IF /
8], and then the silicon mirror wafer is cut into 1 cm squares using a diamond glass cutter [Inoue Seieido Co., Ltd.]. Five pieces were randomly sampled from the cut 1 cm square silicon mirror wafer, and the surface thereof was analyzed by ESCA under the following conditions.
/ Si ratio (average value of 5 samples) is obtained, and the state of contamination of the chip surface by an organic substance is measured. <ESCA measurement conditions>: X-ray source; Mg-Kα ray (125
2.0 eV), X-ray output; 300 W, degree of vacuum measured: 2 ×
10 ⁻⁷ Pa or less, C / Si ratio; (peak area of carbon) /
(Silicon peak area). <Evaluation method of C / Si ratio>: The C / Si ratio on the surface of the silicon mirror wafer before attaching the adhesive film was 0.10.
(Blank value). Therefore, it is evaluated that there is no contamination on the chip surface having a C / Si ratio of about 0.10 to 0.20 on the silicon mirror wafer chip surface after sticking the adhesive film, and on the chip surface exceeding it, Evaluates as having contamination.

(3) Adhesion (%) Semiconductor silicon wafer (diameter:
6 inches, thickness: 600 μm, scribe line depth: 8 μm, scribe line width: 100 μm) A sample adhesive film is adhered to the entire surface of the semiconductor silicon wafer via the adhesive layer via the adhesive layer. And a laser focus microscope (manufactured by KEYENCE, type: VF-
7510, VF-7500, VP-ED100) at 250 magnifications and photograph. As the adhesion evaluation, the ratio of the area of the adhesive to the scribe line and the total area of the scribe line is used as an index of adhesion,
The adhesiveness to the scribe line of the pressure-sensitive adhesive is set to be 70% or more for high adhesion.

Example 1 <Preparation of base film> An ethylene-vinyl acetate copolymer resin having a Shore D-type hardness of 35 was formed into a film having a thickness of 200 µm using a T-die extruder. At this time, the side on which the pressure-sensitive adhesive layer was applied was subjected to corona treatment. The thickness variation of the obtained film was within ± 1.5%.

<Polymerization of Pressure-Sensitive Adhesive> In a polymerization reactor, 150% by weight of deionized water and 4,4′-azobis-4-cyanovaleric acid as a polymerization initiator [Otsuka Chemical Co., Ltd.]
0.625% by weight, 2-ethylhexyl acrylate 63.1% as a monomer (A).
5% by weight, 18% by weight of n-butyl acrylate, and 12% by weight of methyl methacrylate, 3% by weight of 2-hydroxyethyl methacrylate as a monomer (B), 2% by weight of methacrylic acid, and 1% by weight of acrylamide, Polytetramethylene glycol diacrylate [manufactured by NOF Corporation, trade name: ADT-250, n
= 0, m = 3] 0.1% by weight, as a water-soluble comonomer, polymerizable on the benzene ring of the ammonium salt of a sulfate of polyoxyethylene nonylphenyl ether (average number of moles of ethylene oxide added: about 20). 0.75% by weight of a 1-propenyl group-introduced product (Daiichi Kogyo Seiyaku Co., Ltd., trade name: AQUALON HS-10) was charged,
Emulsion polymerization was carried out at 70 to 72 ° C. for 8 hours with stirring to obtain an acrylic resin emulsion. This was neutralized (pH = 7.0) with 9% by weight aqueous ammonia, and the solid content was 4%.
2.5% by weight of an acrylic pressure-sensitive adhesive polymer (pressure-sensitive adhesive base material).

<Preparation of PSA Coating Solution> 100 parts by weight of the obtained PSA base was collected and further adjusted to pH 9.5 by adding 9% by weight aqueous ammonia. Next, 0.8 parts by weight of an aziridine-based cross-linking agent (trade name: Chemitite Pz-33, manufactured by Nippon Shokubai Chemical Industry Co., Ltd.) was added to obtain an adhesive coating solution.

<Preparation of Pressure-sensitive Adhesive Film> The pressure-sensitive adhesive coating solution was applied to a polypropylene film (release film, thickness: 50 μm) using a roll coater.
For 2 minutes to provide an adhesive layer having a thickness of 40 μm. The corona-treated surface of the above-mentioned ethylene-vinyl acetate copolymer film (base film) was adhered to this and pressed to transfer the pressure-sensitive adhesive layer. After the transfer, the film was heated at 60 ° C. for 48 hours, and then cooled to room temperature to produce an adhesive film for grinding the back surface of a semiconductor wafer. The measurement results are shown in [Table 1].

Example 2 In the polymerization of the pressure-sensitive adhesive base material of Example 1, the monomer (A)
Of 2-ethylhexyl acrylate was 62.25% by weight, and polytetramethylene glycol diacrylate [manufactured by NOF CORPORATION, trade name: A as monomer (C)]
DT-250, n = 0, m = 3] was changed to 1% by weight, and the polymerization conditions of the comonomer and the initiator were all the same as in Example 1, and the polymerization of the main adhesive was carried out. An adhesive film for grinding the back surface of a semiconductor wafer was produced in the same manner as in Example 1. Various properties of the obtained pressure-sensitive adhesive film and the contamination status of the obtained chip surface were evaluated in the same manner as in Example 1. The measurement results are shown in [Table 1].

Example 3 In the polymerization of the main adhesive of Example 1, the monomer (A)
Among them, 2-ethylhexyl acrylate was 60.25% by weight, and polytetramethylene glycol diacrylate [manufactured by NOF CORPORATION, trade name:
ADT-250, n = 0, m = 3] was changed to 3% by weight, and the polymerization conditions of the comonomer and the initiator were all the same as in Example 1, and the polymerization of the main adhesive was carried out. An adhesive film for grinding the back surface of a semiconductor wafer was produced in the same manner as in Example 1. Various properties of the obtained pressure-sensitive adhesive film and the contamination status of the obtained chip surface were evaluated in the same manner as in Example 1. The measurement results are shown in [Table 1].

Example 4 In the polymerization of the pressure-sensitive adhesive base material of Example 2, the monomer (A)
After the polymerization of the main adhesive was carried out in the same manner as in Example 2, except that only 92.25% by weight of 2-ethylhexyl acrylate was used, An adhesive film for grinding a back surface of a semiconductor wafer was produced in the same manner as in the above. Various properties of the obtained pressure-sensitive adhesive film and the contamination status of the obtained chip surface were evaluated in the same manner as in Example 1. The measurement results are shown in [Table 1].

Example 5 An epoxy-based cross-linking agent [Denacol Ex, trade name, manufactured by Nagase Kasei Kogyo Co., Ltd.]
-614] to obtain a pressure-sensitive adhesive coating solution.
Thereafter, an adhesive film for grinding the back surface of a semiconductor wafer was produced in the same manner as in Example 1. Various properties of the obtained pressure-sensitive adhesive film and the contamination status of the obtained chip surface were evaluated in the same manner as in Example 1. The measurement results are shown in [Table 1].

Example 6 In the polymerization of the main adhesive of Example 1, the monomer (A)
Using 76.3% by weight of n-butyl acrylate and 16.7% by weight of methyl acrylate as a monomer (C)
And poly (ethylene glycol-tetramethylene glycol) diacrylate [manufactured by NOF Corporation, trade name: AD
ET-1800, n = 15.5, m = 15.5] 1% by weight
Except for using, the polymerization conditions of the comonomer and the initiator were all the same as in Example 1, and after the polymerization of the adhesive main agent was performed, the adhesive film for grinding the back surface of the semiconductor wafer was produced in the same manner as in Example 1. Produced. Various properties of the obtained pressure-sensitive adhesive film and the contamination status of the obtained chip surface were evaluated in the same manner as in Example 1. The measurement results are shown in [Table 2].

Example 7 In the polymerization of the pressure-sensitive adhesive base material of Example 4, the monomer (C) was used.
As polytetramethylene glycol diacrylate [n = 0 m = 3 manufactured by NOF Corporation, trade name: ADT-2
50] instead of poly (propylene glycol-tetraethylene glycol) diacrylate [Nippon Oil & Fats Co., Ltd.
, Trade name: ADPT-4000, n = 0, m = 60] was 1% by weight, and the polymerization conditions of the comonomer and the initiator were all the same as in Example 4 to carry out the polymerization of the main adhesive. After that, an adhesive film for grinding the back surface of a semiconductor wafer was produced in the same manner as in Example 1. Various properties of the obtained pressure-sensitive adhesive film and the contamination status of the obtained chip surface were evaluated in the same manner as in Example 1. The measurement results are shown in [Table 2].

Example 8 In the polymerization of the pressure-sensitive adhesive base material of Example 7, acrylic acid-2
Except that ethylhexyl was 90.25% by weight and poly (propylene glycol-tetraethylene glycol) diacrylate was 3% by weight, the polymerization conditions such as comonomer and initiator were all the same as in Example 7 and the pressure-sensitive adhesive main agent was used. After polymerization, an adhesive film for grinding the back surface of a semiconductor wafer was produced in the same manner as in Example 1. Various properties of the obtained pressure-sensitive adhesive film and the contamination status of the obtained chip surface were evaluated in the same manner as in Example 1. The measurement results are shown in [Table 2].

Example 9 In the polymerization of the main adhesive of Example 7, acrylic acid-2
Except that ethylhexyl was 88.25% by weight and poly (propylene glycol-tetraethylene glycol) diacrylate was 10% by weight, the polymerization conditions such as the comonomer and the initiator were all the same as in Example 7, and the pressure-sensitive adhesive base was used. After polymerization, an adhesive film for grinding the back surface of a semiconductor wafer was produced in the same manner as in Example 1. Various properties of the obtained pressure-sensitive adhesive film and the contamination status of the obtained chip surface were evaluated in the same manner as in Example 1. The measurement results are shown in [Table 2].

Example 10 An epoxy crosslinking agent [Denacol Ex-61, manufactured by Nagase Kasei Kogyo Co., Ltd.] was applied to the same pressure-sensitive adhesive base material as in Example 7.
4] 1.0 part by weight was added to obtain an adhesive coating solution. Thereafter, an adhesive film for grinding the back surface of a semiconductor wafer was produced in the same manner as in Example 1. Various properties of the obtained pressure-sensitive adhesive film and the contamination status of the obtained chip surface were evaluated in the same manner as in Example 1. The measurement results are shown in [Table 2].

[0071]

[Table 1]

[0072]

[Table 2]

Comparative Example 1 In Example 4, the monomer (A) was replaced with acrylic acid-2-
After the polymerization of the main adhesive was carried out in the same manner as in Example 4 except that the amount of ethylhexyl was 93.25% by weight and the monomer (C) was not used, the semiconductor wafer was produced in the same manner as in Example 1. An adhesive film for back grinding was prepared. The adhesive properties of the obtained adhesive film, the state of contamination on the chip surface, and the like were evaluated using the same method as in Example 1. The measurement results are shown in [Table 3].

Comparative Example 2 Polymerization of the main adhesive was carried out in the same manner as in Example 4 except that the monomer (C) was changed to 1% by weight of allyl methacrylate, and the polymerization conditions such as the comonomer and the initiator were all the same. After that, an adhesive film for grinding the back surface of a semiconductor wafer was produced in the same manner as in Example 1. The adhesive properties of the obtained adhesive film, the state of contamination on the chip surface, and the like were evaluated using the same method as in Example 1. Table 3 shows the measurement results.
Shown in

Comparative Example 3 In the polymerization of the pressure-sensitive adhesive base material of Example 8, the monomer (C)
Instead of poly (propylene tetramethylene glycol) diacrylate, polyethylene glycol diacrylate [manufactured by Kyoeisha Chemical Co., Ltd., trade name: 9EG-A, n
= 9, m = 0] The polymerization of the main component of the pressure-sensitive adhesive was carried out under the same polymerization conditions as in Example 8 except that the comonomer and the initiator were changed to 3% by weight. The main agent could not be obtained. The results are shown in [Table 3].

Comparative Example 4 In a mixed solvent of 50 parts by weight of toluene and 65 parts by weight of ethyl acetate, in the presence of 0.7 part by weight of a polymerization initiator [benzoyl peroxide nipper BMT-K40, manufactured by NOF Corporation] When solution polymerization was carried out using the same mixed monomer as in Example 4, gelation occurred during the reaction, and a pressure-sensitive adhesive main agent could not be obtained. The results are shown in Table 3.
Shown in

[0077]

[Table 3]

[0078]

According to the present invention, when grinding the back surface of a semiconductor wafer, not only does the wafer not break during grinding due to the grinding stress on the back surface, but also there is water between the wafer surface and the adhesive layer. In addition, no breakage of the wafer and no contamination of the wafer surface due to infiltration of grinding chips occur. There is no breakage of the wafer when the adhesive film is peeled off from the wafer, and it is not necessary to newly introduce equipment such as a light irradiation device.
Furthermore, since there is no adhesive residue after the adhesive film is peeled off from the wafer, the surface of the semiconductor wafer is not contaminated.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Makoto Kataoka, 2-1-1 Tangodori, Minami-ku, Nagoya, Aichi Prefecture Inside Mitsui Chemicals, Inc. (72) Kentaro Hirai 2-1-1, Tangodori, Minami-ku, Nagoya-shi, Aichi Mitsui Chemicals Co., Ltd. (72) Inventor Hideki Fukumoto 2-1-1 Tangodori, Minami-ku, Nagoya City, Aichi Prefecture Mitsui Chemicals Co., Ltd. (72) Inventor Seiji Miyagawa 2-1-1 Tangodori, Minami-ku, Nagoya City, Aichi Prefecture Mitsui Chemicals F term in the company (reference) 4J004 AA02 AA10 AB01 CA03 CA04 CA06 CC02 DA02 DA03 DB02 FA05 FA08 4J040 DF031 GA01 GA05 GA07 GA22 JA03 KA16 LA06 MA04 MB09 NA20 5F043 AA02 DD16 FF07 GG10

Claims (6)

[Claims] An adhesive film for grinding a back surface of a semiconductor wafer, wherein an adhesive layer is provided on one surface of a base film,
The pressure-sensitive adhesive layer contains 10 to 98.9% by weight of a (meth) acrylic acid alkyl ester-based main monomer unit (A), 1 to 40% by weight of a monomer unit (B) having a functional group capable of reacting with a crosslinking agent, and Formula (1) (In the general formula (1), R ₁ and R ₂ each represent hydrogen or a methyl group. A represents an alkylene oxide unit, and the number of ethylene oxide units (n) in A is 0.
And the number of units (m) of the alkylene oxide having 3 to 12 carbon atoms is 1 to 80, and when n is 0, (n
<M), when n is 1 to 20, (n ≦ m), and these may be random copolymers or block copolymers). .
An acrylic pressure-sensitive adhesive polymer prepared by emulsion polymerization containing 1 to 30% by weight, and a cross-linking agent having two or more functional groups in one molecule with respect to 100 parts by weight of the acrylic pressure-sensitive adhesive polymer. An adhesive film for grinding a back surface of a semiconductor wafer, wherein the adhesive film is formed of an adhesive containing 15 parts by weight. 2. The back grinding of a semiconductor wafer according to claim 1, wherein the (meth) acrylic acid alkyl ester-based main monomer unit (A) is a (meth) acrylic acid alkyl ester unit having an alkyl group having 1 to 12 carbon atoms. Adhesive film. 3. The monomer unit (B) having a functional group capable of reacting with a crosslinking agent is selected from acrylic acid, methacrylic acid, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, acrylamide and methacrylamide. The pressure-sensitive adhesive film for grinding a back surface of a semiconductor wafer according to claim 1, wherein the pressure-sensitive adhesive film is at least one selected from monomer units. 4. The back grinding of a semiconductor wafer according to claim 1, wherein (A) is 85 to 95% by weight, (B) is 1 to 10% by weight, and (C) is 0.1 to 5% by weight. Adhesive film. 5. A base film having a thickness of 10 to 500 μm.
The pressure-sensitive adhesive film according to claim 1, wherein the pressure-sensitive adhesive layer has a thickness of 3 to 100 µm. 6. A method for grinding the back surface of a semiconductor wafer using the adhesive film for grinding the back surface of a semiconductor wafer according to claim 1, wherein the adhesive for grinding the back surface of the semiconductor wafer is attached to a circuit forming surface of the semiconductor wafer. A method of grinding a back surface of a semiconductor wafer, comprising attaching a film, grinding the back surface of the semiconductor wafer, and peeling the adhesive film after the grinding is completed.