Manufacturing method of electronic component device

Abstract

Provided is an adhesive composition comprising: a compound that generates an acid by at least one of heating or irradiation with an active energy ray; and a protected compound that has, in the molecule, a hydrophilic group protected by a protective group, said hydrophilic group being deprotected by the acid.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority from Japanese Patent Application No. 2023-173900, the entire disclosure of which is incorporated herein by reference. [Technical Field]

[0002] The present invention relates to a pressure-sensitive adhesive composition and a pressure-sensitive adhesive sheet used for producing electronic component devices such as semiconductor integrated circuits, etc. The present invention also relates to a method for producing an electronic component device using the pressure-sensitive adhesive composition or the pressure-sensitive adhesive sheet. [Background technology]

[0003] Conventionally, there have been known methods for manufacturing electronic component devices, such as semiconductor integrated circuits, in which a substrate, such as a silicon wafer, is divided into small pieces to produce a large number of chips. During such processing, when the substrate is divided into small pieces, a small portion of the substrate may become tiny pieces, resulting in minute foreign matter. If circuit components such as circuit wiring or electrode portions are arranged on one side of the substrate, minute foreign matter may adhere to the circuit wiring or electrode portions. Furthermore, foreign matter may also adhere to the other side, on which circuit components such as circuit wiring or electrode portions are not arranged. If a large amount of foreign matter adheres to the surface of the substrate, the reliability of the manufactured electronic component device as a product may be reduced, regardless of whether circuit components are arranged on the side to which the foreign matter adheres.

[0004] In response to this, there is known a method for manufacturing an electronic component device in which a protective adhesive tape is attached to at least one surface of a substrate and then the above-described processing is carried out (for example, Patent Document 1).

[0005] The method for manufacturing an electronic component device described in Patent Document 1 uses a semiconductor protective adhesive tape having a substrate and a photocurable adhesive layer (adhesive layer) superimposed on one side of the substrate. The substrate has a specific thickness and is designed to have a specific heat shrinkage rate after heating at 150°C for 30 minutes. The photocurable adhesive layer (adhesive layer) is formed from a composition with a specific blending composition, has a specific thickness, and is designed to have a relatively small, specific adhesive strength after light irradiation. More specifically, in the method for manufacturing an electronic component device described in Patent Document 1, first, a photocurable adhesive layer (adhesive layer) of a protective adhesive tape is superimposed on the circuit surface of a substrate (hereinafter referred to as a semiconductor package) on which a circuit is formed, and the protective adhesive tape and the semiconductor package are separated into small pieces while superimposed. Next, the small semiconductor packages and the protective adhesive tape are attached to the temporary fixing tape so that the circuit surface of the small semiconductor packages faces the temporary fixing tape and so that the temporary fixing tape and the base material of the protective adhesive tape are in contact. Subsequently, a metal film is formed on a portion of the surface of the semiconductor package in the temporarily fixed state. Finally, the circuit surface of the semiconductor package and the photocurable adhesive layer are peeled off to pick up the semiconductor package.

[0006] According to the method for manufacturing an electronic component device described in Patent Document 1, when the semiconductor package and protective adhesive tape are processed into small pieces, the circuit surface of the semiconductor package can be protected by covering it with the protective adhesive tape. The protective adhesive tape can then be removed by peeling the circuit surface of the semiconductor package from the photocurable adhesive layer of the protective adhesive tape fixed to the temporary fixing tape. The peel force required to remove the photocurable adhesive layer (adhesive layer) of the protective adhesive tape is weakened by curing the photocurable adhesive layer through light irradiation. Furthermore, heat generated when forming a metal film on a portion of the surface of the semiconductor package generates shrinkage stress (residual strain) inside the substrate, which can easily deform the substrate due to the shrinkage stress (residual strain), making the peeling more likely to occur. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 2021-147579 Summary of the Invention [Problem to be solved by the invention]

[0008] However, in the manufacturing method of an electronic component device described in Patent Document 1, it is necessary to adjust, for example, the peeling speed to prevent the circuit surface from being damaged by the peeling force when peeling between the circuit surface of the semiconductor package and the photocurable adhesive layer (adhesive layer), and the process of removing the adhesive layer is not necessarily simple. Furthermore, the use of temporary fixing tape for the above-mentioned peeling can make the process of removing the adhesive layer complicated. Furthermore, after peeling, part of the photocurable adhesive layer (adhesive layer) may remain on the circuit surface, making it not necessarily easy to remove the photocurable adhesive layer (adhesive layer). Even if the photocurable adhesive layer (adhesive layer) overlapping the non-circuit surface where no circuit surface is formed is removed, the above-mentioned problems can occur.

[0009] Therefore, there is a demand for an adhesive composition that can not only protect at least one surface to be protected (surface to be protected) of a substrate or the like during processing by covering the surface to be protected, but also form an adhesive layer that can be relatively easily removed from the surface to be protected after processing or the like is completed. In particular, there is a need for a pressure-sensitive adhesive composition that can form a pressure-sensitive adhesive layer that is relatively easily removed when contacted with a solvent such as water.

[0010] However, it cannot be said that sufficient research has been conducted yet on adhesive compositions for forming adhesive layers that can not only cover and protect the surface to be protected, but also be relatively easily removed by contact with a liquid containing water after protection.

[0011] Therefore, an object of the present invention is to provide a pressure-sensitive adhesive composition for forming a pressure-sensitive adhesive layer that can be relatively easily removed upon contact with a liquid containing water after protecting a surface to be protected. Another object of the present invention is to provide a pressure-sensitive adhesive sheet including a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition. Another object of the present invention is to provide a method for manufacturing an electronic component device using the pressure-sensitive adhesive layer. [Means for solving the problem]

[0012] In order to solve the above problems, the pressure-sensitive adhesive composition according to the present invention comprises: a compound that generates an acid upon at least one of heating and irradiation with active energy rays; and a compound to be protected, the compound having in its molecule a hydrophilic group protected by a protecting group, the hydrophilic group being deprotected by the acid.

[0013] The pressure-sensitive adhesive sheet according to the present invention comprises a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition.

[0014] The method for manufacturing an electronic component device according to the present invention includes: a step of protecting at least one of the surfaces to be protected of the substrate by overlaying an adhesive layer formed from an adhesive composition on the surface to be protected; and removing the adhesive layer that overlaps the surface to be protected, The pressure-sensitive adhesive composition comprises a compound that generates an acid upon at least one of heating and irradiation with active energy rays, and a protected compound that has, in the molecule, a hydrophilic group that is protected by a protecting group and that can be deprotected by the acid, In the removing step, the acid is generated from a compound that generates the acid by at least one of heating and irradiation with active energy rays, thereby increasing the hydrophilicity of the adhesive layer, and the adhesive layer is removed by contacting it with a liquid containing water. [Brief explanation of the drawings]

[0015] [Figure 1]1 is a schematic cross-sectional view of an example of a pressure-sensitive adhesive sheet according to an embodiment of the present invention, cut in the thickness direction. [Figure 2A] 5A and 5B are schematic cross-sectional views illustrating an example of a protection step in the method for manufacturing an electronic component device according to the present embodiment. [Figure 2B] 5A and 5B are schematic cross-sectional views illustrating an example of a protection step in the method for manufacturing an electronic component device according to the present embodiment. [Figure 2C] FIG. 3 is a schematic cross-sectional view showing an example of a state before a substrate is cut in the manufacturing method of an electronic component device according to the present embodiment. [Figure 2D] 5 is a schematic cross-sectional view showing an example of a state after the substrate is cut in the manufacturing method of the electronic component device according to the embodiment. FIG. [Figure 2E] 5A and 5B are schematic cross-sectional views illustrating an example of a removing step in the method for manufacturing an electronic component device according to the present embodiment. [Figure 2F] 5A and 5B are schematic cross-sectional views illustrating an example of a removing step in the method for manufacturing an electronic component device according to the present embodiment. [Figure 3A] FIG. 2 is a cross-sectional view of an example of a dicing tape cut in the thickness direction. [Figure 3B] FIG. 2 is a cross-sectional view of an example of a dicing die bond film cut in the thickness direction. [Figure 4A] FIG. 10 is a cross-sectional view schematically illustrating a state after a mounting step and a protection step are performed in the embodiment. [Figure 4B] 5A and 5B are cross-sectional views schematically illustrating a state during a blade dicing process in the present embodiment. [Figure 4C] FIG. 10 is a cross-sectional view schematically illustrating a state after a blade dicing process is performed in the present embodiment. [Figure 4D] 5A to 5C are cross-sectional views schematically illustrating a removal step in the present embodiment. [Figure 4E] 5A to 5C are cross-sectional views schematically illustrating a removal step in the present embodiment. [Figure 4F] 5A to 5C are cross-sectional views schematically illustrating a pickup process in the present embodiment. [Figure 4G] 5A to 5C are cross-sectional views schematically illustrating a joining step in the present embodiment. [Figure 4H]10 is a cross-sectional view schematically illustrating a state of half-cut processing of a semiconductor wafer in another example of the present embodiment. FIG. [Figure 4I] 10 is a cross-sectional view schematically illustrating a state of half-cut processing of a semiconductor wafer in another example of the present embodiment. FIG. [Figure 4J] 10 is a cross-sectional view schematically illustrating a state of half-cut processing of a semiconductor wafer in another example of the present embodiment. FIG. [Figure 4K] 10A to 10C are cross-sectional views schematically illustrating a mounting process in another example of the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, embodiments of the pressure-sensitive adhesive composition, the pressure-sensitive adhesive sheet, and the method for producing an electronic component device according to the present invention will be described in order with reference to the drawings.

[0017] The pressure-sensitive adhesive composition of the present embodiment is a composition containing a compound that generates an acid upon at least one of heating and irradiation with active energy rays, and a protected compound having, in its molecule, a hydrophilic group that is protected by a protecting group and that can be deprotected by the acid. The pressure-sensitive adhesive composition of the present embodiment is used, for example, to form an adhesive layer that protects a surface to be protected of a substrate that constitutes an electronic component device.

[0018] By overlaying an adhesive layer formed from the above-mentioned adhesive composition on a surface to be protected, it is possible to prevent foreign matter from adhering to the surface of the substrate to be protected (the surface to be protected) until the adhesive layer overlaid on such surface is removed. For example, when processing is performed to break down the substrate and adhesive layer into small pieces while the adhesive layer formed from the adhesive composition and the substrate are overlapped, foreign matter such as fragments that may be generated during the cutting into small pieces can be prevented from adhering to the surface to be protected, thereby protecting the surface to be protected. Furthermore, by subjecting the adhesive layer to a heat treatment or active energy ray irradiation treatment, an acid is generated from the acid-generating compound. As a result, the protecting group that protected the hydrophilic group of the protected compound is released from the hydrophilic group, thereby increasing the hydrophilicity of the adhesive layer formed from the adhesive composition. The adhesive layer with increased hydrophilicity swells upon contact with a liquid containing water and can be relatively easily peeled from the surface to be protected. Therefore, the adhesive layer is easily released from the surface to be protected. Therefore, the adhesive layer can be easily removed from the surface to be protected, compared to, for example, a case where a release tape is attached to the adhesive layer and the adhesive layer is removed together with the release tape. In this way, the adhesive layer formed from the above-mentioned adhesive composition can not only protect the surface to be protected of the substrate, which is a component of the electronic component device being manufactured, but also, after protection, can be relatively easily removed from the surface to be protected using a liquid containing water.

[0019] In this embodiment, the compound that generates an acid is, for example, an acid generator that generates an acid upon at least one of heating and irradiation with active energy rays. Examples of the compound that generates an acid include a photoacid generator and a thermal acid generator.

[0020] The pressure-sensitive adhesive composition contains the acid-generating compound, and therefore has a property that its hydrophilicity increases upon at least one of heating and irradiation with active energy rays such as ultraviolet rays. The pressure-sensitive adhesive composition has a predetermined level of hydrophilicity or higher after the hydrophilic group of the protected compound is deprotected. Therefore, in a state in which the hydrophilic group of the protected compound is protected, the pressure-sensitive adhesive composition may have a hydrophilicity less than the predetermined level or a hydrophilicity equal to or higher than the predetermined level. When the pressure-sensitive adhesive composition has a hydrophilicity equal to or higher than the predetermined level, an adhesive layer formed from the pressure-sensitive adhesive composition can swell in a liquid containing water. The compound that generates an acid is preferably a compound that generates an acid upon irradiation with active energy rays (particularly ultraviolet rays).

[0021] The compound to be protected has at least a hydrophilic group and a protecting group that protects the hydrophilic group in the molecule. In other words, the compound to be protected is a compound that contains a hydrophilic group protected by a protecting group. The compound to be protected may be a low molecular weight compound or a high molecular weight compound.

[0022] Examples of the hydrophilic group protected by a protecting group include a carboxy group (-COOH), a hydroxy group (-OH), a sulfo group (-SO3H), and an amino group (-NH2).

[0023] Examples of the protecting group capable of protecting the hydrophilic group include the following protecting groups. When the hydrophilic group to be protected is a carboxy group, examples of the protecting group include a tert-butyl group, an alkoxyalkyl group, or a cyclic acetal (dioxolane) group. Examples of the alkoxyalkyl group include a methoxymethyl group, an ethoxyethyl group, a propoxyethyl group, a butoxyethyl group, or a cyclohexoxyethyl group. In the alkoxyalkyl group, the number of consecutively bonded carbon atoms may be 2 or more and 4 or less. When the hydrophilic group to be protected is a hydroxy group, examples of the protecting group include a trityl group, an alkoxymethyl group, a tetrahydropyranyl group, a cyclic acetal (dioxolane) group, a tert-butyldimethylsilyl group, or a (tert-)butoxycarbonyl group. When the hydrophilic group to be protected is an amino group, examples of the protecting group include a (tert-)butoxycarbonyl group.

[0024] The above-mentioned protecting group exists in the protected compound in a state chemically bonded to a hydrophilic group. The above-mentioned notation of the protecting group does not necessarily directly represent the state in which the hydrophilic group and the protecting group are bonded. For example, when the hydrophilic group is a carboxy group and the protecting group is a tert-butyl group, an ester bond is formed by the reaction of the carboxy group with tert-butyl alcohol. Even in such a case, the protecting group is described as a tert-butyl group. The hydrophilic groups to be protected are also shown with their names before protection.

[0025] When the protecting group is removed from the hydrophilic group (deprotection), the protecting group portion is removed from the hydrophilic group portion. The compound derived from the removed protecting group may or may not be volatile, for example.

[0026] The above-mentioned protected compound may have, in the molecule, a structural unit of a (meth)acrylic acid type monomer containing a hydrophilic group protected by a protecting group. In other words, the above-mentioned protected compound may be a polymer obtained by polymerizing a protected (meth)acrylic acid type monomer containing a hydrophilic group protected by a protecting group. The expression "protected (meth)acrylic acid type monomer" includes both a monomer in which the carboxy group of (meth)acrylic acid is protected and a monomer in which the hydrophilic group in a (meth)acrylic acid ester is protected. Examples of the above-mentioned protected (meth)acrylic acid type monomer include a protected carboxy group-containing (meth)acrylic monomer in which the carboxy group is protected by a protecting group, a protected hydroxyalkyl (meth)acrylate monomer in which the hydroxy group is protected by a protecting group, and a protected 2-acrylamido-2-methylpropanesulfonic acid monomer in which the sulfo group is protected by a protecting group.

[0027] Examples of the compound to be protected include oligomers or polymers having a structural unit of a protected (meth)acrylic acid type monomer containing a hydrophilic group protected by a protecting group. The oligomer may be, for example, an oligomer in which 3 to 10 protected carboxy group-containing (meth)acrylic monomers, each having a carboxy group protected with a protecting group, are bonded together through a polymerization reaction. The oligomer may be, for example, an oligomer in which 3 to 10 protected hydroxyalkyl (meth)acrylate monomers, each having a hydroxy group protected by a protecting group, are bonded together through a polymerization reaction. The oligomer may be, for example, an oligomer in which 3 to 10 protected (meth)acrylamide alkylsulfonic acid monomers, each having a sulfo group protected with a protecting group, are bonded together through a polymerization reaction.

[0028] The polymer or oligomer as the protected compound has, for example, a main chain and a plurality of side chains in the molecule. The main chain is, for example, a covalently bonded chain formed by a radical polymerization reaction. At least a part of the main chain is preferably a covalently bonded chain formed by a polymerization reaction of a protected (meth)acrylic acid type monomer containing a carboxyl group protected by a protecting group as a hydrophilic group. The side chains have, for example, hydrophilic groups, such as hydroxy or carboxy groups, which are protected by protecting groups in the side chains of the polymer or oligomer.

[0029] The above oligomer may be a homopolymer of a monomer containing a hydrophilic group protected by a protecting group, or may be a copolymer of a monomer containing a hydrophilic group protected by a protecting group and a monomer other than such a monomer. Similarly, the polymer may be a homopolymer or copolymer of a monomer containing a hydrophilic group protected by a protecting group, and the average molecular weight of the polymer may be 50,000 or more and 900,000 or less.

[0030] Since the above polymer or oligomer contains a hydrophilic group such as a hydroxy group or a carboxy group protected by a protecting group in the molecule, the adhesive layer formed from the adhesive composition has low hydrophilicity when the hydrophilic group is protected. Therefore, even when contacted with a solvent containing water, the adhesive layer is not removed from the surface to be protected and continues to protect the surface to be protected. On the other hand, after the adhesive layer is subjected to a treatment such as heating or irradiation with active energy rays, the protected hydrophilic group is deprotected, thereby increasing the hydrophilicity of the adhesive layer formed from the above adhesive composition. Therefore, as described above, the adhesive layer swells and can be removed from the surface to be protected relatively easily.

[0031] The above polymer or oligomer is preferably a (meth)acrylic polymer containing at least the structural unit of the above (meth)acrylic monomer containing a protected carboxy group in the molecule. Examples of the constituent unit of the protected carboxy group-containing (meth)acrylic monomer include a constituent unit of a protected (meth)acrylic acid monomer in which the carboxy group is protected by a protecting group, and a constituent unit of a protected carboxyalkyl (meth)acrylate monomer in which the carboxy group is protected by a protecting group. A specific example of the structural unit of the protected (meth)acrylic acid monomer is a structural unit of a protected acrylic acid monomer or a protected methacrylic acid monomer. A specific example of the structural unit of the protected carboxyalkyl (meth)acrylate monomer is a structural unit of a protected carboxyethyl (meth)acrylate.

[0032] The (meth)acrylic polymer preferably contains 50% by mass or more, more preferably 80% by mass or more, of the structural units of the (meth)acrylic monomer having a protected carboxy group in the molecule. The (meth)acrylic polymer may contain 95% by mass or more of the structural units of the (meth)acrylic monomer having a protected carboxy group. When the (meth)acrylic polymer contains a larger amount of the structural units of the protected carboxy group-containing (meth)acrylic monomer, the adhesive layer formed from the adhesive composition has higher water resistance, while the adhesive layer that has been subjected to a heat treatment or active energy ray irradiation treatment in the removal step (described in detail later) can be more easily removed with a liquid containing water.

[0033] Examples of monomers copolymerizable with the above-mentioned protected (meth)acrylic acid type monomers include vinyl acetate (vinyl acetate), alkyl (meth)acrylates [(meth)acrylic acid alkyl esters], hydroxyalkyl (meth)acrylates [(meth)acrylic acid hydroxyalkyl esters], carboxyalkyl (meth)acrylates [(meth)acrylic acid carboxyalkyl esters], (meth)acrylic acid, and (meth)acrylates having polyethylene glycol chains. In other words, the above-mentioned (meth)acrylic polymers may contain, in addition to the structural units of the above-mentioned protected carboxy group-containing (meth)acrylic monomers, the structural units of the above-listed monomers in the molecule. In the above-mentioned (meth)acrylic polymers, the content of the structural units of alkyl (meth)acrylates [(meth)acrylic acid alkyl esters] may be less than 5% by mass (including 0% by mass). In this specification, the term "(meth)acrylic" encompasses both "acrylic" and "methacrylic." The same applies to "(meth)acrylate."

[0034] The alkyl (meth)acrylate is preferably an alkyl (meth)acrylate having 6 to 22 carbon atoms in the alkyl moiety. Examples of preferred alkyl (meth)acrylates include hexyl (meth)acrylate, octyl (meth)acrylate, decyl (meth)acrylate, lauryl (meth)acrylate, myristyl (meth)acrylate, palmityl (meth)acrylate, stearyl (meth)acrylate, arachidyl (meth)acrylate, and behenyl (meth)acrylate. When the alkyl (meth)acrylate has 6 to 22 carbon atoms in the alkyl moiety, the glass transition temperature (Tg) of the (meth)acrylic polymer becomes relatively low, which may make the (meth)acrylic polymer easier to handle. The hydrocarbon portion may be linear or branched, and is preferably composed solely of saturated hydrocarbons.

[0035] The (meth)acrylic polymer is preferably a (meth)acrylic copolymer having at least in the molecule a structural unit of a (meth)acrylic monomer containing a protected carboxy group and a structural unit of the alkyl (meth)acrylate.

[0036] In this embodiment, the acid-generating compound is a compound that newly generates an acid by at least one of a heat treatment and an active energy ray irradiation treatment. The heat treatment and the active energy ray irradiation treatment will be described in detail later.

[0037] The compound that generates the acid may be a photoacid generator or a thermal acid generator, and a photoacid generator is preferred because it can more reliably deprotect the protecting group. Note that one compound may have both the functions of a photoacid generator and a thermal acid generator. In other words, for example, a specific acid generator may generate an acid by both heat treatment and irradiation with active energy rays. When the acid-generating compound generates an acid by light irradiation or heat treatment, the protecting group in the protected compound contained in the adhesive layer is deprotected, revealing a hydrophilic group. This increases the hydrophilicity of the adhesive layer. Therefore, when the adhesive layer comes into contact with a liquid containing water, the adhesive layer can be more easily removed from the surface to be protected.

[0038] The photoacid generator as the acid generator is, for example, a photocationic polymerization initiator that is generally used for cationic polymerization, and the thermal acid generator as the acid generator is, for example, a thermal cationic polymerization initiator that is generally used for cationic polymerization. As the photoacid generator or thermal acid generator, commercially available products can be used.

[0039] Photoacid generators include ionic and nonionic types. Ionic photoacid generators have a cationic structure and an anionic structure. Examples of ionic photoacid generators, depending on the type of cationic structure, include onium salt compounds, sulfonimide compounds, and disulfonyldiazomethane compounds.

[0040] Examples of the onium salt compound include onium salt compounds such as iodonium salt compounds, sulfonium salt compounds, oxime sulfonate compounds, and diazonium salt compounds. Of these, iodonium salt compounds or sulfonium salt compounds are preferred, and sulfonium salt compounds are more preferred.

[0041] Examples of iodonium salt compounds include diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroarsenate, bis(4-t-butylphenyl)iodonium hexafluorophosphate, diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoronormal butanesulfonate, diphenyliodonium perfluoronormal octanesulfonate, diphenyliodonium camphorsulfonate, bis(4-tert-butylphenyl)iodonium camphorsulfonate, bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate, bis(4-fluorophenyl)iodonium triflate, diphenyliodonium hexafluorophosphate, etc. Other examples include the iodonium salt compounds used in the following examples.

[0042] Examples of sulfonium salt compounds include diphenyl[4-(phenylsulfanyl)phenyl]sulfonium=trifluorotris(pentafluoroethyl)-λ 5-phosphanide, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium nonafluoro-normal butanesulfonate, triphenylsulfonium camphorsulfonate, 4,7-di-n-butoxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate, triphenylsulfonium trifluoromethanesulfonate, benzyl-4-hydroxyphenylmethylsulfonium hexafluorophosphate, triphenylsulfonium adamantanecarboxylate trifluoroethanesulfonate, triphenylsulfonium p-toluenesulfonate, triphenylsulfonium methanesulfonate, triphenylsulfonium phenolsulfonate, triphenylsulfonium nitrate, triphenylsulfonium maleate, bis(triphenylsulfonium)maleate, triphenylsulfonium hydrochloride (triphenylsulfonium chloride), triphenylsulfonium acetate, triphenylsulfonium trifluoroacetate, triphenylsulfonium salicylate, triphenylsulfonium benzoate, triphenylsulfonium hydroxide, and the like. Other examples include the sulfonium salt compounds used in the following examples.

[0043] Examples of the oxime sulfonate compound include (5-propylsulfonyloxyimino-5H-thiophen-2-ylidene)-(2-methylphenyl)acetonitrile, (5-octylsulfonyloxyimino-5H-thiophen-2-ylidene)-(2-methylphenyl)acetonitrile, (camphorsulfonyloxyimino-5H-thiophen-2-ylidene)-(2-methylphenyl)acetonitrile, (5-p-toluenesulfonyloxyimino-5H-thiophen-2-ylidene)-(2-methylphenyl)acetonitrile, and (5-octylsulfonyloxyimino)-(4-methoxyphenyl)acetonitrile.

[0044] Examples of the diazonium salt compound include 4-nitrobenzenediazonium tetrafluoroborate.

[0045] Examples of commercially available onium salt compounds include Optomer SP-150, Optomer SP-170, and Optomer SP-171 (all manufactured by ADEKA Corporation), UVE-1014 (manufactured by General Electronics Corporation), OMNICAT250 and OMNICAT270 (both manufactured by IGM Resin), IRGACURE290 (manufactured by BASF), San-Aid SI-60L, San-Aid SI-80L, and San-Aid SI-100L (all manufactured by Sanshin Chemical Industry Co., Ltd.), CPI-100B, CPI-100P, CPI-101A, and CPI-200K (all manufactured by San-Apro Co., Ltd.).

[0046] Examples of sulfonimide compounds as photoacid generators include N-(trifluoromethanesulfonyloxy)succinimide, N-(nonafluoronormalbutanesulfonyloxy)succinimide, N-(camphorsulfonyloxy)succinimide, N-(trifluoromethanesulfonyloxy)naphthalimide, N-(camphorsulfonyloxy)succinimide, N-(4-methylphenylsulfonyloxy)succinimide, N-(2-trifluoromethylphenylsulfonyloxy)succinimide, N-(4-fluorophenylsulfonyloxy)succinimide, N-(trifluoromethylsulfonyloxy)phthalimide, N-(camphorsulfonyloxy)phthalimide, N-(2-trifluoromethylphenylsulfonyloxy)phthalimide, N-(2-fluorophenylsulfonyloxy)phthalimide, N-(trifluoromethylsulfonyloxy)diphenylmaleimide, N-(camphorsulfonyloxy)diphenylmaleimide, and N-(4-methylphenylsulfonyloxy)diphenylmaleimide.

[0047] Examples of disulfonyldiazomethane compounds as photoacid generators include bis(trifluoromethylsulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, bis(phenylsulfonyl)diazomethane, bis(p-toluenesulfonyl)diazomethane, bis(2,4-dimethylbenzenesulfonyl)diazomethane, and methylsulfonyl-p-toluenesulfonyldiazomethane.

[0048] Other examples of photoacid generators include 2,4-bis(trichloromethyl)-6-[2-(furan-2-yl)vinyl]-1,3,5-triazine.

[0049] Examples of the thermal acid generator include sulfonium salts such as aryl diazonium salts, diaryliodonium salts, triaryl sulfonium salts, diaryl monoalkyl sulfonium salts, triaryl sulfoxonium salts, pyridinium salts, quinolinium salts, isoquinolinium salts, sulfonic acid esters, iron arene complexes, etc. Examples of the anion constituting the sulfonium salt include trifluorotris(perfluoroethyl)phosphate and hexafluorophosphate.

[0050] The acid generator, such as a photoacid generator or a thermal acid generator, preferably has good compatibility with the polymer contained in the pressure-sensitive adhesive composition. As the acid generator, an ionic acid generator is preferred, and an ionic photoacid generator is more preferred.

[0051] In the pressure-sensitive adhesive composition, the amount of the acid-generating compound relative to 100 parts by mass of the compound to be protected is preferably 0.2 parts by mass or more, more preferably 1.0 part by mass or more, whereby the pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition can have higher hydrophilicity after heat treatment or active energy ray irradiation treatment, and therefore is more likely to swell in a liquid containing water. The amount of the acid-generating compound per 100 parts by mass of the compound to be protected is preferably 10 parts by mass or less, which can more sufficiently prevent the acid-generating compound from remaining in the pressure-sensitive adhesive composition.

[0052] In addition to the above-mentioned components, the pressure-sensitive adhesive composition of the present embodiment may further contain, for example, a solvent, a surfactant, etc. Examples of the solvent include water and an organic solvent. The organic solvent is preferably a relatively volatile organic solvent, such as ethanol or methanol.

[0053] The pressure-sensitive adhesive composition of the present embodiment preferably does not contain either a photopolymerization initiator or a thermal polymerization initiator. If the pressure-sensitive adhesive composition of the present embodiment contains a photopolymerization initiator or a thermal polymerization initiator, the protected hydrophilic group in the above-mentioned protected compound may chemically react with the photopolymerization initiator or the thermal polymerization initiator. When this reaction occurs, the hydrophilic group may disappear and change into an organic group that does not have hydrophilicity. Therefore, the pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition may be difficult to maintain its hydrophilicity even after being subjected to a heat treatment or an active energy ray irradiation treatment. Therefore, it may be difficult to remove the pressure-sensitive adhesive layer using a liquid containing water.

[0054] The PSA composition of the present embodiment may be a solid having no fluidity, or may have fluidity. When the PSA composition contains a solvent, it may have fluidity.

[0055] The pressure-sensitive adhesive composition of the present embodiment can be produced by mixing the above-mentioned polymer, the above-mentioned acid-generating compound such as the photoacid generator, and, if necessary, a solvent, etc., by a general method. Alternatively, the pressure-sensitive adhesive composition of the present embodiment may be produced by volatilizing the solvent after the above-mentioned mixing.

[0056] The pressure-sensitive adhesive composition of the present embodiment is used, for example, to produce a pressure-sensitive adhesive sheet, which will be described later.

[0057] Next, the adhesive sheet 10 of this embodiment will be described.

[0058] 1, the pressure-sensitive adhesive sheet 10 of this embodiment includes at least a pressure-sensitive adhesive layer 11. The pressure-sensitive adhesive sheet 10 of this embodiment may further include a release liner 15 that overlaps at least one surface of the pressure-sensitive adhesive layer 11. The release liner 15 may be overlapped on one or both surfaces of the pressure-sensitive adhesive layer 11. It should be noted that the figures in the drawings are schematic diagrams and do not necessarily have the same aspect ratio as the actual product. The same applies to the other drawings.

[0059] In this embodiment, the adhesive layer 11 of the adhesive sheet 10 is formed into a sheet shape from the above-mentioned adhesive composition. When the above-mentioned adhesive sheet 10 is used, for example, the release liner 15 is peeled off from the adhesive layer 11, and the adhesive layer 11 is attached to at least one surface (surface to be protected) of a substrate.

[0060] The adhesive layer 11 has flexibility that allows it to be deformed by a relatively weak force. The adhesive layer 11 also has adhesiveness that allows it to adhere to the surface of a substrate to be protected. In other words, the adhesive layer 11 can be used as a pressure-sensitive sheet adhesive that can be adhered to the surface to be protected by being pressed against the surface to be protected.

[0061] In this embodiment, the contact angle of water of the adhesive layer 11 that has not been subjected to heating or irradiation with active energy rays may be 70° or more and less than 120°. On the other hand, heating and irradiation with active energy rays (2500 mJ / cm from a high-pressure mercury lamp) 2 The contact angle of water of the adhesive layer 11 after being subjected to at least one of the irradiations (irradiation of the adhesive layer 11 with water) is preferably 100° or less.

[0062] The contact angle is measured as follows. Specifically, the contact angle of water on one surface of the adhesive layer 11 (the surface to be attached to the surface to be protected) is measured using a general contact angle meter. More specifically, in accordance with JIS R3257, the contact angle with 0.15 μL of water is measured at 25° C. using a fully automatic contact angle measuring device (for example, product name: DM-500 manufactured by Kyowa Interface Science Co., Ltd.). The average value of five measurements is used. The contact angle is measured 30 seconds after water is dropped onto the smooth surface of a molded product (for example, adhesive layer 11) molded from the adhesive composition. When the adhesive composition contains an organic solvent, the contact angle is measured on the molded product (for example, adhesive layer 11) from which the organic solvent has been removed.

[0063] In this embodiment, the water contact angle of the adhesive layer 11 after being subjected to at least one of heating (heating treatment) and the above-mentioned irradiation (irradiation treatment) (hereinafter sometimes simply referred to as "after treatment") is preferably 3° or more smaller, and more preferably 10° or more smaller, than the water contact angle of the adhesive layer 11 before being subjected to either heating (heating treatment) or irradiation with active energy rays (irradiation treatment) (before treatment). By increasing the change in the contact angle, it is possible to more fully achieve both the water resistance of the adhesive layer 11 before the treatment and the water swelling properties (good water penetration into the adhesive layer 11) of the adhesive layer 11 after the treatment. The change in the contact angle may be 50° or less.

[0064] The contact angle of the adhesive layer 11 after the above-mentioned treatment is a measured value measured after the above-mentioned treatment is carried out under the following conditions. (When the adhesive layer contains a photoacid generator) Active energy ray irradiation treatment: 2500mJ / cm using a high-pressure mercury lamp 2 After irradiation, Heat treatment: 100°C for 30 seconds, then leave for 30 minutes (When the adhesive layer contains a thermal acid generator) Heat treatment: 100°C for 1 hour, then leave for 30 minutes

[0065] The adhesive layer 11 may be formed, for example, by applying the solvent-containing adhesive composition to one surface of a substrate and then volatilizing the solvent. Alternatively, the adhesive layer 11 may be formed by applying the solvent-containing adhesive composition to one surface of a release liner 15 and then volatilizing the solvent. The formed adhesive layer 11 preferably does not contain a solvent blended to impart fluidity to the adhesive composition. The adhesive layer 11 may be formed, for example, from the above-mentioned adhesive composition containing no solvent by a general molding method.

[0066] In the above-mentioned pressure-sensitive adhesive sheet, the thickness of the pressure-sensitive adhesive layer 11 is not particularly limited, but is, for example, 1 μm or more and 100 μm or less. Such a thickness may be 3 μm or more, or 5 μm or more. Also, such a thickness may be 40 μm or less. Note that when the pressure-sensitive adhesive layer 11 is a laminate, the above thickness is the total thickness of the laminate.

[0067] The adhesive layer 11 may have physical properties that allow it to be divided into small pieces by being stretched in the planar direction. Adhesive layer 11 having such physical properties is suitable for use in manufacturing electronic component devices through a stealth processing step using a stealth dicing device, which will be described later. Similarly, it is suitable for use in manufacturing electronic component devices through a DBG process (described in detail later). The adhesive layer 11 does not need to have the physical properties described above, since it can also be suitably used when manufacturing electronic component devices through a blade dicing process (described in detail later).

[0068] The protective sheet 1 of this embodiment is used, for example, during the process of manufacturing an electronic component device. Specifically, the protective sheet 1 of this embodiment is used for purposes such as temporarily protecting the surface to be protected (the surface to be protected) of an electronic component (a type of substrate). More specifically, the protective sheet 1 of this embodiment is used, for example, by being attached to the surface to be protected of the electronic component (a type of substrate). Examples of the electronic component include a semiconductor wafer, a semiconductor chip, a substrate such as a wired circuit board, a connected wired circuit board formed by connecting a plurality of wired circuit boards, and a pseudo wafer.

[0069] The semiconductor chip typically has a semiconductor chip body and electrodes disposed on one or both sides of the semiconductor chip body and electrically connected to electrodes of another component, such as a wiring circuit board or another semiconductor chip. The semiconductor chip has, for example, at least one surface formed with a circuit surface on which a circuit is formed. Specifically, the semiconductor chip may be a TSV (Through Silicon Via) type semiconductor chip having a pair of electrode portions arranged on both sides of the semiconductor chip body, and a conductive portion that penetrates the semiconductor chip body in the thickness direction so as to electrically connect one of the electrode portions to the other. In a TSV type semiconductor chip, a circuit surface may be formed on only one side, or a circuit surface may be formed on each of both sides. The circuit of the semiconductor chip may also include a sensor element (e.g., a light receiving element or a vibration element) as an element. This type of semiconductor chip is, for example, a sensor chip. Examples of the sensor chip include a CMOS (Complementary Metal-Oxide Semiconductor) chip and a MEMS (Micro Electro Mechanical Systems) chip.

[0070] The pseudo wafer includes, for example, a support substrate and a package body in which a plurality of semiconductor chips arranged on the support substrate are collectively sealed with resin. The pseudo wafer may be the package body removed from the support substrate. A rewiring layer may be formed on at least a portion of the surface of the pseudo wafer. The protective sheet 1 may be used to cover the rewiring layer. Note that the divided bodies obtained by dividing the pseudo wafer into constituent units each including at least one semiconductor chip may be electronic components.

[0071] As described above, there are various types of electronic components that have surfaces to be protected, and various electronic components can serve as the substrate.

[0072] Next, a method for manufacturing the electronic component device of this embodiment will be described.

[0073] The method for manufacturing an electronic component device according to this embodiment includes the steps of: a step of protecting the surface to be protected by overlaying an adhesive layer 11 formed from an adhesive composition on at least one of the surfaces to be protected of both surfaces of the substrate (protection step); and a step of removing the adhesive layer 11 overlapping the surface to be protected (removal step), The pressure-sensitive adhesive composition comprises a compound that generates an acid upon at least one of heating and irradiation with active energy rays, and a protected compound that has, in the molecule, a hydrophilic group that is protected by a protecting group and that can be deprotected by the acid, In the removal step, the acid is generated from a compound that generates the acid by at least one of heating and irradiation with active energy rays, thereby increasing the hydrophilicity of the adhesive layer 11, and the adhesive layer 11 is removed by contacting it with a liquid containing water.

[0074] In the above protection step, as shown in Fig. 2A, the surface to be protected of the substrate S may be protected using an adhesive sheet 10 having a release liner 15 on one side of an adhesive layer 11. For example, after the adhesive layer 11 of the adhesive sheet 10 is superimposed on the surface to be protected of the substrate S, the release liner 15 may be peeled off from the adhesive layer 11 (see Fig. 2B).

[0075] As shown in FIGS. 2C and 2D , the manufacturing method of the electronic component device of this embodiment further includes: The method may include a step of dividing the stacked laminate of substrate S and adhesive layer 11 into small pieces at intervals in the surface direction, thereby producing a plurality of stacked small pieces of chips S' formed by dividing the substrate into small pieces and small pieces 11' of adhesive layer. Note that the substrate S before division may have a fragile portion formed inside for dividing into small pieces.

[0076] In the above-mentioned removal process, as shown in Figure 2E, multiple small pieces 11' of the adhesive layer are subjected to, for example, a heating treatment or irradiation treatment with active energy rays such as ultraviolet rays, thereby generating new acid from the acid-producing compounds contained in each small piece 11' and increasing the hydrophilicity of each small piece 11'. Then, in the above-mentioned removing step, each small piece 11' of the adhesive layer overlapping the circuit surface of the chip S' is removed by a liquid containing water, as shown in FIG. 2F. The method for manufacturing an electronic component device of this embodiment may further include a step of placing the circuit surface of the chip S' facing the adherend and bonding the chip S' to the adherend.

[0077] The electronic component device manufactured by the manufacturing method of this embodiment includes at least one of the various electronic components described above. Examples of the electronic component device include a semiconductor device such as a semiconductor integrated circuit including a semiconductor chip, a device including a system LSI having a complementary MOS (CMOS), or a device including a device (MEMS Micro Electro Mechanical Systems) in which mechanical elements, sensors, actuators, or electronic circuits are integrated by microfabrication technology on a single silicon substrate, glass substrate, or organic material substrate. The manufactured electronic component device may also include a device including a wiring circuit board.

[0078] In the method for manufacturing an electronic component device according to this embodiment, at least one surface of the substrate is protected by an adhesive layer. The surface to be protected (hereinafter simply referred to as the surface to be protected) may be only one surface of the substrate or both surfaces. Circuit components (described in detail below) may or may not be arranged on the surface to be protected.

[0079] The substrate may be made of any material, as long as it is plate-shaped. Examples of the substrate material include glass, silicon, stainless steel (SUS), plastic, and ceramic. Examples of the substrate include a semiconductor wafer, a sensor wafer such as a CMOS or MEMS, a pseudo wafer, and a wiring circuit board.

[0080] In the above-mentioned protection step, an adhesive layer 11 may be overlaid on the surface of the substrate on which at least one of the circuit wiring, the sensor unit, and the electrode unit is arranged as a circuit component. For example, the adhesive layer 11 may be overlaid on one side (circuit surface) of the substrate on which the circuit wiring is arranged, the adhesive layer 11 may be overlaid on one side of the substrate on which the sensor unit is arranged, or the adhesive layer 11 may be overlaid on one side of the substrate on which the electrode unit is arranged. In the above-mentioned protection step, it is preferable to overlay the adhesive layer 11 on at least one side of the substrate so as to cover the circuit wiring, the sensor unit, or the electrode unit with the adhesive layer 11. Examples of the circuit component include circuit wiring, an electrode unit, or elements such as a transistor, a diode, or a sensor unit (such as a light-receiving sensor or a vibration sensor).

[0081] Hereinafter, a detailed description will be given of the case where a semiconductor integrated circuit (semiconductor device) is manufactured as an electronic component device.

[0082] Generally, a method for manufacturing a semiconductor device includes a front-end process in which a circuit surface is formed on one side of a wafer using highly integrated electronic circuits, and a back-end process in which chips are cut out from the wafer with the circuit surface formed and assembled.

[0083] In a post-process, for example, a fragile portion is formed on the wafer (semiconductor wafer) as a substrate on which a circuit surface is formed, for dicing into small semiconductor chips (dies), and an adhesive fixing layer of dicing tape is attached to the surface opposite the circuit surface. Then, while the semiconductor wafer is attached to the adhesive fixing layer of the dicing tape, the dicing tape is stretched in the planar direction, dicing the semiconductor wafer into semiconductor chips along the fragile portion. The diced semiconductor chips are then peeled off from the adhesive fixing layer of the dicing tape.

[0084] The above-mentioned post-processing includes, for example, a stealth processing step in which fragile portions for dividing the wafer into small chips (dies) are formed in the wafer using laser light or the like, a mounting step in which the surface of the semiconductor wafer opposite the circuit surface is attached to a dicing tape to fix the semiconductor wafer, an expanding step in which the semiconductor wafer is divided into semiconductor chips (dies) by stretching the dicing tape in the surface direction, a pick-up step in which the semiconductor chips are peeled off from the adhesive fixing layer and removed, and a bonding step in which the removed semiconductor chips are bonded to an adherend. A semiconductor integrated circuit (semiconductor device) is manufactured through, for example, these steps.

[0085] In the method for manufacturing a semiconductor device (electronic component device) of this embodiment, for example, semiconductor chips are cut out from a semiconductor wafer on which a circuit surface is formed, and a semiconductor device having the cut-out semiconductor chips is assembled. In the method for manufacturing a semiconductor device of this embodiment, a semiconductor device is manufactured as follows using at least the adhesive layer 11 of the adhesive sheet 10 and a dicing tape 20 (see FIG. 3A). These sheets and tapes are used as auxiliary tools for manufacturing a semiconductor device. It is also possible to use a dicing die bond film in which a die bond sheet 30 is superimposed on the adhesive fixing layer 22 of the dicing tape 20 (see FIG. 3B). Commercially available products can be used as the dicing tape 20 and the dicing die bond film.

[0086] An embodiment of the method for manufacturing a semiconductor device will be described in detail below.

[0087] The method for manufacturing a semiconductor device according to this embodiment includes an assembly process in which semiconductor chips X are cut out from a semiconductor wafer W (substrate) on which a circuit surface is formed, and a semiconductor device having such semiconductor chips X is assembled. The assembly process includes a step (protection step) of protecting the circuit surface (surface to be protected) by overlaying an adhesive layer 11 for protecting the circuit components on at least one surface of the semiconductor wafer W, on which any of the circuit components are formed; a step of dividing a stack of overlapping semiconductor wafers (W) and adhesive layers (11) into small pieces at intervals in a surface direction, thereby producing a plurality of small pieces of a stack of semiconductor chips (X) obtained by dividing the semiconductor wafers (W) into small pieces and adhesive layer small pieces (11') that are overlapping each other; a step of subjecting each small piece 11' of the adhesive layer overlapping the circuit surface of the semiconductor chip X to a heat treatment or an active energy ray irradiation treatment to generate an acid from the acid-generating compound in each small piece 11', thereby increasing the hydrophilicity of each small piece 11', and then removing each small piece 11' of the adhesive layer with a liquid containing water (removal step); and a step of bonding the semiconductor chip X to the adherend.

[0088] The assembly process of this embodiment includes, for example, the following steps. Specifically, the assembly process of this embodiment includes the following steps: a mounting step of attaching a semiconductor wafer W having circuit components formed on one side thereof to a dicing die bond film (a die bond sheet 30 superimposed on a dicing tape 20) to fix the semiconductor wafer W to the dicing die bond film; a protection step of protecting the circuit surface by attaching an adhesive layer 11 to the circuit surface of the semiconductor wafer W; a blade dicing process (a process for producing a plurality of small pieces of the laminate) in which the semiconductor wafer W to which the die bond sheet 30 and the adhesive layer 11 are attached is diced by a dicing blade T or the like to produce semiconductor chips (dies) by dicing the semiconductor wafer W; a removing step (the removing step) of removing the plurality of small pieces 11' of the adhesive layer attached to the semiconductor chip X after the above-mentioned heating treatment or active energy ray irradiation treatment, etc.; a pick-up step of peeling the die-bonding sheet piece 30' from the dicing tape 20 to take out the semiconductor chip X with the die-bonding sheet piece 30' attached; and a bonding step (the above-mentioned bonding step) of bonding the extracted semiconductor chip X to an adherend via the die-bonding sheet piece 30'. When these steps are carried out, the above-mentioned adhesive layer 11 and the dicing die-bonding film having the dicing tape 20 are used as manufacturing aids.

[0089] The semiconductor wafer W is configured to obtain a plurality of semiconductor chips X. Specifically, the semiconductor wafer W is configured to be divided into small pieces at intervals in a plurality of directions along its surface (for example, directions along its surface that are perpendicular to each other), thereby enabling the manufacture of a plurality of semiconductor chips X. The semiconductor wafer W also has a circuit surface on at least one surface on which at least one type of circuit component is arranged. For example, the semiconductor wafer W used in this embodiment has a circuit surface formed on one of its surfaces.

[0090] In recent years, with the further advancement of integration technology in the semiconductor industry, there has been a demand for thinner semiconductor chips (for example, thicknesses of 20 μm to 50 μm). When viewed from one side in the thickness direction, the shape of a semiconductor chip is, for example, rectangular, with a side length of, for example, 5 mm to 20 mm.

[0091] In the mounting step, as shown in FIG. 4A, a dicing ring R is attached to the adhesive fixing layer 22 of the dicing tape 20, and a semiconductor wafer W is attached and fixed to a die bond sheet 30 superimposed on the dicing tape 20.

[0092] In the protection step, as shown in Fig. 4A, for example, an adhesive layer 11 is superimposed on one of the circuit surfaces of the semiconductor wafer W. In the protection step, for example, the adhesive layer 11 may be superimposed on the circuit surface by directly pressing the adhesive layer 11 against the circuit surface to adhere it. Alternatively, an adhesive composition containing solid components that constitute the adhesive layer 11 and a solvent that dissolves the solid components may be prepared, and the prepared adhesive composition may be applied to the circuit surface, followed by volatilizing the solvent to form an adhesive layer 11 that contacts the circuit surface, thereby superimposing the adhesive layer 11 on the circuit surface. By overlapping the adhesive layer 11 on the circuit surface of the semiconductor wafer W, the circuit surface can be protected by the adhesive layer 11 until the adhesive layer 11 is removed. Therefore, it is possible to prevent dust and the like from adhering to the circuit surface of the semiconductor wafer W covered with the adhesive layer 11. The protection step may be performed after the mounting step, or the mounting step may be performed after the protection step.

[0093] In the blade dicing process, the semiconductor wafer W is diced, for example, as shown in Figures 4B and 4C. Specifically, the semiconductor wafer W is cut to a predetermined size together with the die bond sheet 30 to form semiconductor chips with the die bond sheet 30. The blade dicing process is performed in a conventional manner, for example, using a dicing blade T. In the blade dicing process, for example, a cutting method called full cut, in which the cut is made up to the die bond sheet 30, can be used. The dicing device used in the blade dicing process is not particularly limited, and conventionally known devices can be used. In the blade dicing process, foreign matter such as debris may be generated when the semiconductor wafer W is cut. At this time, the surface of the semiconductor wafer W to be protected is protected by the adhesive layer 11, so that the adhesion of foreign matter to the surface to be protected can be suppressed. Before the blade dicing process, the dicing ring R may be attached to the adhesive fixing layer 22 of the dicing tape 20, and then the dicing ring R may be fixed to the holder H of the expanding device.

[0094] In the removal step, as shown in Fig. 4D, the adhesive layer pieces 11' are subjected to a treatment to generate an acid from the acid-generating compound, which may be at least one of a heat treatment and an active energy ray irradiation treatment. The heat treatment is carried out, for example, by exposing the adhesive layer pieces 11' to an environment of 90°C or higher and 250°C or lower for 10 minutes or longer and 300 minutes or shorter. In the irradiation treatment of active energy rays, for example, 10 mW / cm 2 More than 300mW / cm 2 UV rays with an intensity of less than 50mJ / cm are used as active energy rays. 2 More than 5000mJ / cm 2 The adhesive layer pieces 11' are irradiated with ultraviolet light as follows. In the removal step, the adhesive layer fragments 11' are subjected to the above-described treatment, whereby an acid is generated from the acid-generating compound contained in the fragments 11'. The newly generated acid causes protecting groups to be removed from the protected compounds contained in the adhesive layer fragments 11', generating unprotected hydrophilic groups. This increases the hydrophilicity of the adhesive layer fragments 11'. As a result, when the fragments 11' later come into contact with a liquid containing water, the fragments 11' swell, allowing them to be removed relatively easily from the surface of the semiconductor chip X.

[0095] In the removal process, as shown in Figure 4E, a liquid containing water is brought into contact with multiple small pieces 11' of the adhesive layer, and each small piece 11' is swelled by the liquid, thereby removing each small piece 11' of the adhesive layer from the surface (surface to be protected) of the semiconductor chip X. By removing the adhesive layer pieces 11' in this manner, all of the adhesive layer pieces 11' can be removed relatively easily, and the number of foreign matters adhering to the semiconductor chip surfaces can be reduced relatively easily using the liquid. Also, the surfaces (surfaces to be protected) of the semiconductor chips X on which the adhesive layer pieces 11' overlap can be washed with the liquid.

[0096] In the removal step, the adhesive layer that has been broken into small pieces (the plurality of small pieces 11' of the adhesive layer) is swollen by the liquid. As a result, the adhesive force of the small pieces 11' of the adhesive layer to the semiconductor chip X is weakened, and the small pieces 11' of the adhesive layer become more easily peeled off from the semiconductor chip X. This allows the plurality of small pieces 11' of the adhesive layer to be removed relatively easily. Furthermore, the adhesive layer fragments 11' peeled off from the semiconductor chip X swell with the liquid, but do not all dissolve in the liquid in a short time. Therefore, the adhesive layer fragments 11' can be collected relatively easily. This reduces the load on the device used in the removal process and also reduces the environmental load when disposing of the liquid.

[0097] The water-containing liquid is not particularly limited as long as it is a liquid substance containing water, and may contain 30% by mass or more of water, 50% by mass or more, 70% by mass or more, 80% by mass or more, or 90% by mass or more of water. The liquid may contain, in addition to water, a component that dissolves in water. Examples of such components include water-soluble organic solvents. Examples of such water-soluble organic solvents include monohydric alcohols having four or fewer carbon atoms, such as methanol, ethanol, propanols such as isopropyl alcohol, and butanols such as t-butanol.

[0098] In the removal step of this embodiment, the adhesive layer pieces 11' may be immersed in the stirred liquid to bring the liquid into contact with the adhesive layer pieces 11'. Alternatively, the liquid may be sprayed from a nozzle or the like to bring the adhesive layer pieces 11' into contact with the liquid. The temperature of the liquid is not particularly limited and may be set to, for example, 10°C or higher and 90°C or lower.

[0099] For example, in the removal step, the liquid is sprayed toward the semiconductor chips X attached to the die bond sheet pieces 30' while rotating a disk-shaped stage supporting the dicing tape 20 from below in the circumferential direction. This makes it possible to remove the adhesive layer pieces 11' overlapping the semiconductor chips X. The rotation speed of the stage may be, for example, 500 rpm or more and 4000 rpm or less, the amount of liquid sprayed may be, for example, 0.05 L / min or more and 5.0 L / min or less, and the spraying time may be, for example, 5 seconds or more and 300 seconds or less.

[0100] According to the semiconductor device manufacturing method of this embodiment, the adhesive layer 11 is superimposed on the surface (circuit surface) of the semiconductor wafer W on which the circuit components are formed, so that the circuit surface can be protected until the adhesive layer 11 is removed. Specifically, the semiconductor wafer W is diced into small pieces while the semiconductor wafer W and the adhesive layer 11 are superimposed, to produce the semiconductor chips X. This prevents foreign matter, such as fragments that may be generated when the semiconductor wafer W is cleaved, from adhering to the circuit surface of the semiconductor chips X. Even if foreign matter is adhering to the circuit surface of the semiconductor chips X before the adhesive layer 11 is superimposed, the foreign matter can be removed when the small pieces 11' of the adhesive layer superimposed on the circuit surface of the semiconductor chips X are removed. This prevents foreign matter from adhering to the circuit surface of the semiconductor chips X to be manufactured.

[0101] In the pick-up process, as shown in Fig. 4F, the semiconductor chip X is peeled off from the adhesive fixing layer 22 of the dicing tape 20. More specifically, the pin members P are raised to push up the semiconductor chip X to be picked up through the dicing tape 20. The pushed-up semiconductor chip X is held by the suction jig J.

[0102] When performing the pick-up step in this way, it is necessary that the pieces 30' of the die bond sheet attached to the semiconductor chip X be easily peeled off from the adhesive fixing layer 22 of the dicing tape 20. Furthermore, when performing the above-mentioned expanding step, it is necessary to stretch the dicing tape 20 so that the die bond sheet 30, the semiconductor wafer W, and the adhesive layer 11 are suitably divided into small pieces as necessary. The above-mentioned dicing tape 20 is designed to be able to satisfactorily exhibit such performance. For example, the dicing tape 20 is configured so that, when irradiated with active energy rays (e.g., ultraviolet rays), the adhesive fixing layer 22 hardens and the adhesive strength of the adhesive fixing layer 22 decreases. Since the adhesive fixing layer 22 hardens after irradiation, the adhesive strength of the adhesive fixing layer 22 can be reduced, and therefore the semiconductor chip X and the small piece 30′ of the die bond sheet can be relatively easily peeled off from the adhesive fixing layer 22 after irradiation. Dicing tapes 20 configured in this way are commercially available.

[0103] In the bonding process, the semiconductor chip X with the die bond sheet piece 30' attached thereto is bonded to the adherend Z. In other words, the semiconductor chip X is bonded to the adherend Z via the die bond sheet piece 30'. In the bonding process, as shown in FIG. 4G, the semiconductor chips X with the die bond sheet piece 30' attached thereto may be stacked multiple times. In this embodiment, the semiconductor chip X is bonded to the adherend such as a substrate or semiconductor chip X via the die bond sheet piece 30'. When stacking a plurality of semiconductor chips X as described above in the bonding process, the semiconductor chips X are stacked in such a way that adhesion of foreign matter to the circuit surfaces is suppressed, and therefore the number of foreign matter entering between one stacked semiconductor chip X and the other stacked semiconductor chip X can be reduced. The adherend Z may be, for example, an interposer, a wiring circuit board, or a small piece of substrate (when small pieces of substrate are stacked and laminated).

[0104] In this embodiment, in order to protect the semiconductor chip X after the bonding step, a resin sealing step may be performed in which the semiconductor chip X is sealed (covered) with a thermosetting resin or the like.

[0105] In the above description of this embodiment, an example has been given in which the semiconductor wafer W is divided into small pieces by a blade dicing process, but the semiconductor wafer W may also be divided into small pieces through a so-called DBG process in which the thickness of the semiconductor wafer W is reduced after half-cutting the semiconductor wafer W. In half-cut processing, for example, grooves are formed in the semiconductor wafer W to process the semiconductor wafer W into chips (dies) by a cleaving process, and the semiconductor wafer W is then ground to reduce its thickness. In the half-cut process, for example, as shown in FIGS. 4H to 4K, a wafer processing tape E is attached to the surface of the semiconductor wafer W opposite the circuit surface. With the wafer processing tape E attached, grooves for division are formed. A back-grinding tape B is attached to the surface with the grooves formed, while the wafer processing tape E that was initially attached is peeled off. With the back-grinding tape B attached, the semiconductor wafer W is ground until it reaches a predetermined thickness. Then, a mounting process is performed, and the semiconductor device is then manufactured in the same manner as described above.

[0106] The semiconductor wafer W (substrate) before being diced into semiconductor chips X may be ground to a desired thickness by back-grinding, for example. Specifically, in the back-grinding, the semiconductor wafer W having a back-grinding tape B attached to its circuit surface may be ground to reduce the thickness of the semiconductor wafer W to the thickness of the semiconductor chips X to be fabricated later.

[0107] Processes other than those shown in the above specific examples may also be performed. For example, in processes such as plasma dicing and stealth dicing, the adhesive layer 11 may be superimposed on the circuit surface of the semiconductor wafer W, and after various processing steps are performed, the adhesive layer 11 may be removed. Alternatively, with the adhesive layer 11 disposed between the backgrinding tape B and the semiconductor wafer W as described above, the grinding process may be performed as described above, and then the mounting process may be performed.

[0108] The methods for producing the pressure-sensitive adhesive composition, pressure-sensitive adhesive sheet, and electronic component device according to the embodiments of the present invention are as exemplified above, but the present invention is not limited to the methods for producing the pressure-sensitive adhesive composition, pressure-sensitive adhesive sheet, and electronic component device exemplified above. That is, various forms used in general pressure-sensitive adhesive compositions, pressure-sensitive adhesive sheets, and methods for producing electronic component devices can be employed within the scope that does not impair the effects of the present invention.

[0109] For example, as described above, the semiconductor wafer used in the manufacturing method of the present invention may be a semiconductor wafer having circuit surfaces formed on both sides, or, as described in other embodiments, a semiconductor wafer having a circuit surface formed on only one side. In other words, the semiconductor chip produced by the manufacturing method of the present invention may have circuit components arranged on only one side of the two sides, or may have circuit components arranged on both sides.

[0110] The matters disclosed by this specification include the following. (1) a compound that generates an acid upon at least one of heating and irradiation with active energy rays; a compound to be protected, the compound having in its molecule a hydrophilic group protected by a protecting group, the hydrophilic group being capable of being deprotected by the acid. Such a pressure-sensitive adhesive composition can form, for example, an adhesive layer that covers at least one surface of a substrate in an electronic component to be manufactured, and is then relatively easily removed when brought into contact with a liquid containing water. (2) The pressure-sensitive adhesive composition according to (1) above, wherein the protected compound has, in the molecule, a structural unit of a protected carboxy group-containing (meth)acrylic monomer that contains a carboxy group protected by the protecting group. (3) On the surface of a molded article of the pressure-sensitive adhesive composition described in (1) or (2) above, the contact angle before the heating or the irradiation of the active energy rays is 70° or more and less than 120°, The heating or the irradiation of the active energy rays was performed using a high-pressure mercury lamp at 2500 mJ / cm 2 The pressure-sensitive adhesive composition has a contact angle of 100°C or less after being exposed to at least one of the above irradiations. (4) In the surface of a molded article of the pressure-sensitive adhesive composition according to any one of (1) to (3), relative to the contact angle of water before being subjected to either the heating or the irradiation of the active energy rays, The heating or the irradiation of the active energy rays was performed using a high-pressure mercury lamp at 2500 mJ / cm 2 The pressure-sensitive adhesive composition has a water contact angle that is 3° or more smaller after being exposed to at least one of the above irradiations. (5) A pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition according to any one of (1) to (4) above. (6) The pressure-sensitive adhesive sheet according to (5) above, further comprising a release liner superimposed on at least one surface of the pressure-sensitive adhesive layer. (7) a step of protecting at least one of the surfaces to be protected of the substrate by overlaying an adhesive layer formed from an adhesive composition on the surface to be protected; and removing the adhesive layer that overlaps the surface to be protected, The pressure-sensitive adhesive composition comprises a compound that generates an acid upon at least one of heating and irradiation with active energy rays, and a protected compound that has, in the molecule, a hydrophilic group that is protected by a protecting group and that can be deprotected by the acid, A method for manufacturing an electronic component device, wherein the removing step involves generating the acid from a compound that generates the acid by at least one of heating or irradiation with active energy rays, thereby increasing the hydrophilicity of the adhesive layer, and removing the adhesive layer by contacting it with a liquid containing water. According to this method for manufacturing an electronic component device, the adhesive layer can prevent foreign matter from adhering to the surface to be protected, and the adhesive layer can then be removed relatively easily by bringing a liquid containing water into contact with the adhesive layer. (8) The method for manufacturing an electronic component device according to (7) above, wherein a circuit component is disposed on the surface to be protected of the substrate. [Example]

[0111] The present invention will now be described in more detail with reference to experimental examples, but the present invention is not limited to these examples.

[0112] Each adhesive composition (adhesive layer) of the Examples and Comparative Examples was prepared, and each adhesive sheet having an adhesive layer was manufactured as follows. Details of each adhesive composition (adhesive layer) in each manufacturing method and evaluation results are shown in Tables 1 and 2.

[0113] [Examples 1 to 10, Comparative Examples 1 and 2] (Preparation of Protected Compounds) According to the compositions shown in Tables 1 and 2, (meth)acrylic polymers were prepared as compounds to be protected. Specifically, the monomers shown in Tables 1 and 2, a polymerization initiator (azobisisobutyronitrile AIBN), and a reaction solvent (ethyl acetate) were mixed so that the solid content was 23% by mass. A solution polymerization reaction was carried out at a temperature of 65°C to 69°C to synthesize a polymer. Details of the monomers are as follows: <Protected (meth)acrylic acid type monomer (monomer containing a protected hydrophilic group)> [Protected Monomer 1] t-Butyl acrylate (tBA) Purchased [ka] [Protected Monomer 2] n-Butoxyethyl Acrylate (BEA) Purchased [ka] [Protected Monomer 3] n-Butoxyethyl Methacrylate (BEMA) Purchased [ka] [Protected Monomer 4] Cyclohexoxyethyl acrylate (CHEA) Purchased [ka] [Protected Monomer 5] n-Propoxyethyl Acrylate (PEA) Purchased [ka] <Other monomers> [BA] n-Butyl acrylate (monomer without protective group) purchased [BMA] n-Butyl methacrylate (monomer without protective group) [4HBA] 4-Hydroxybutyl acrylate (non-protecting group monomer) purchased

[0114] (Preparation of adhesive sheet) An acid-generating compound (photoacid generator) was added to and mixed with the polymer solutions containing each polymer prepared as described above in the amounts shown in Tables 1 and 2 relative to the polymer solids. Each polymer solution was applied to release liner a (PET film, 50 μm thick). Each release liner a had a surface that had been treated with a silicone release agent, and the polymer solution was applied to this surface using an applicator. This was then dried at 130°C for 2 minutes to form a 5 μm thick adhesive layer on one side of release liner a. Release liner b (PET film, 25 μm thick) was then superimposed on the exposed surface of each adhesive layer. Each release liner b had a surface that had been treated with a silicone release agent, and this surface was attached to the adhesive layer. In this way, pressure-sensitive adhesive sheets comprising an adhesive layer (adhesive composition) sandwiched between two release liners were prepared.

[0115] Details of the acid generating compound are as follows: All of the following raw materials are 50% by mass propylene carbonate solutions. [Photoacid generator] Sulfonium salt type, product name "CPI-200K" manufactured by San-Apro Co., Ltd. Chemical Name:Diphenyl[4-(phenylsulfanyl)phenyl]sulfonium trifluorotris(pentafluoroethyl)-λ 5 -Phosphanoid [Also known as: Diphenyl[4-(phenylthio)phenyl]sulfonium, trifluorotris(1,1,2,2,2-pentafluoroethyl)phosphate(1-) (1:1)] Sulfonium salt type, product name "CPI-101A" manufactured by San-Apro Co., Ltd. Chemical Name: Diphenyl[p-(phenylthio)phenyl]sulfonium hexafluoroantimonate Sulfonium salt type, product name "CPI-310FG" manufactured by San-Apro Co., Ltd. [Thermal acid generator] Sulfonium salt type, product name "TA-100FG" manufactured by San-Apro Co., Ltd.

[0116] (pseudo protection process) Release liner b was peeled off and removed from the prepared adhesive sheet to expose one side of the adhesive layer. This exposed side was then bonded to a bare silicon wafer (substrate) on dicing tape using a laminator heated to 90°C. The bare silicon wafer was used instead of a semiconductor wafer. The dicing tape used was a commercially available product (product name "V-12SR" manufactured by Nitto Denko Corporation).

[0117] Thereafter, a blade dicing process was carried out by a conventional method.

[0118] (Removal process) 2,500mJ / cm2 from a high-pressure mercury lamp on the adhesive layer 2 The adhesive layer was then subjected to irradiation treatment (light irradiation treatment including ultraviolet light) to enhance its hydrophilicity. To remove the adhesive layer, a cleaning unit (product name DFD6361) manufactured by DISCO was used to carry out the removal process as follows: While rotating the circular stage supporting the dicing tape from below in the circumferential direction, water at 25°C was sprayed onto the small pieces of adhesive layer on the silicon chip. The stage rotation speed was 1000 rpm, and the water spraying time was 90 seconds.

[0119] [Table 1]

[0120] [Table 2]

[0121] <Physical properties: Change in contact angle on the surface of the adhesive layer (Before UV irradiation / heat treatment and after UV irradiation / heat treatment) 2,500 mJ / cm2 applied to the adhesive composition (adhesive layer) attached to the bare wafer 2An irradiation treatment was performed in which light containing ultraviolet light was irradiated so that the integrated light intensity was 100°C. Furthermore, a heat treatment was performed at 100°C for 30 seconds. The amount of water dropped was 0.15 μL, and the contact angle was measured before the above treatment (irradiation treatment and heat treatment) and 30 minutes after the end of the treatment. The contact angle was measured at 25°C 30 seconds after the water was dropped. Only in Example 10 (containing a thermal acid generator), the contact angle was measured in the same manner as above after only the heat treatment at 100° C. for 1 hour. The evaluation was carried out according to the following method. Specifically, when the contact angle before treatment is defined as a degree and the contact angle after irradiation treatment and heat treatment is defined as b degree, ab<3 Bad(×) ab≧3 Good (〇) Of the above "good" grades, ab≧10 was judged as excellent (◎). The results of the change in contact angle are shown in Tables 1 and 2.

[0122] <Evaluation: Adhesive layer removability / swelling peelability (after UV irradiation)> With the adhesive layer attached to the substrate (bare silicon wafer) (undiced), the irradiation process was carried out in the same manner as in the removal process described above. Furthermore, a heat treatment was carried out at 100°C for 30 seconds. Next, a water spraying process was carried out in the same manner as in the removal process described above. Then, an evaluation was made as to whether the adhesive layer formed from the adhesive composition swelled and was peeled and removed from the substrate (bare silicon wafer) according to the following evaluation criteria. (Excellent) ◎ The adhesive layer swelled and peeled off, resulting in complete removal. (Good) ○ The adhesive layer swelled, but some of it remained without peeling. (Poor) × The adhesive layer swelled and did not peel off, with most of it remaining. Before UV irradiation, the adhesiveness to the substrate (bare silicon wafer) was good for all adhesive layers.

[0123] <Evaluation: Ease of removing adhesive layer (after UV irradiation)> The bare wafer substrate with the adhesive layer formed from each adhesive composition attached thereto was diced (cut into small pieces) into 1 cm squares. The small test samples (small adhesive layers and chips) were irradiated with ultraviolet light at the same intensity as above. Thereafter, the test samples were placed in a beaker containing 100 mL of water, and the water was stirred with a stirrer for 3 minutes. After 3 minutes, the test samples were cut into 1 cm squares. 2 It was visually confirmed whether the adhesive layer (adhesive composition) peeled from the chip of each area remained in substantially the same shape. The evaluation criteria for ease of removal of the adhesive layer are as follows: (Good) ○ The adhesive layer peels off and the shape of the peeled adhesive layer can be confirmed (the adhesive layer is removed all at once in a relatively short time) (Bad) × The adhesive layer does not peel off

[0124] As can be seen from the above evaluation results, by manufacturing a semiconductor device using the semiconductor device manufacturing method of the embodiment, the surface to be protected can be protected. Furthermore, in the removal process, the multiple pieces of adhesive layer could be removed relatively easily with water. Therefore, semiconductor devices can be manufactured efficiently.

[0125] By carrying out the method for manufacturing a semiconductor device according to the embodiment as described above, it is possible to efficiently manufacture a semiconductor device in which a plurality of semiconductor chips are stacked together, with almost no foreign matter adhering thereto. [Industrial Applicability]

[0126] The method for manufacturing an electronic component device of the present invention is suitably used for manufacturing a semiconductor device having, for example, a semiconductor integrated circuit. [Explanation of symbols]

[0127] 10: adhesive sheet, 11: adhesive layer, 11': small piece of adhesive layer, 15: release liner, 20: dicing tape, 21: Base material layer, 22: Adhesive fixing layer, 30: Die bond sheet, G: Glass carrier, W: semiconductor wafer, X: semiconductor chip, V: through via, D: electrode portion, B: Back grind tape.

Claims

[Claim 1] a step of protecting at least one of the surfaces to be protected of the substrate by overlaying an adhesive layer formed from an adhesive composition on the surface to be protected; and removing the adhesive layer that overlaps the surface to be protected, The pressure-sensitive adhesive composition comprises a compound that generates an acid upon at least one of heating and irradiation with active energy rays, and a protected compound that has, in the molecule, a hydrophilic group that is protected by a protecting group and that can be deprotected by the acid, A method for manufacturing an electronic component device, wherein the removing step involves generating the acid from a compound that generates the acid by at least one of heating or irradiation with active energy rays, thereby increasing the hydrophilicity of the adhesive layer, and removing the adhesive layer by contacting it with a liquid containing water.

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