Composition for forming coating film for foreign substance removal and semiconductor substrate

Abstract

Disclosed is a composition for forming a coating film for foreign substance removal, which contains a polymer and a solvent and can form a coating film that can be removed by a removal liquid, wherein the polymer contains a structural unit (A) that has a ring structure containing an -O-C(=O)-(O)m- group (in which m represents 0 or 1).　Also disclosed is a composition wherein the structural unit (A) is a structural unit represented by formula (A-1). (In formula (A-1), R1 represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and X1 represents an ester group or an amide group. Y1 represents a single bond or an alkylene group having 1 to 6 carbon atoms. Q represents an optionally substituted ring structure (r) that has 3 to 10 carbon atoms and comprises a lactone ring or a carbonate ring. The ring structure (r) may be a polycyclic ring.)

Description

Coating film-forming composition for removing foreign matter and semiconductor substrate

[0001] The present invention relates to a coating film-forming composition for removing foreign matter, which can prevent foreign matter from remaining on a substrate in a simple manner, a coating film for removing foreign matter, a semiconductor substrate, and a method for producing a processed semiconductor substrate.

[0002] In the manufacture of semiconductor devices, particularly in the so-called post-processing, a process is being considered in which a semiconductor substrate (e.g., a wafer) is attached to a support substrate, then back-grinding (grinding), wiring formation processes, etc. are performed, and then the support substrate is peeled off to obtain a desired semiconductor substrate.

[0003] In such a process, foreign matter may be generated and must be removed. For example, Patent Documents 1 and 2 disclose a composition for forming a substrate processing film and a substrate processing method that can efficiently remove fine particles from the substrate surface and easily remove the formed substrate processing film from the substrate surface in a process of forming a substrate processing film on the surface of a semiconductor substrate and removing foreign matter from the substrate surface.

[0004] International Publication No. WO 2017 / 056746 International Publication No. WO 2020 / 008965

[0005] On the other hand, when attaching a semiconductor substrate to a support substrate, the semiconductor substrate is attached using an adhesive layer (e.g., a liquid composition containing a polymer, backgrinding tape, dicing tape, etc.) that is resistant to subsequent processes (e.g., heating processes, chemical treatment processes, etc.). Alternatively, a support substrate having a pressure-sensitive adhesive layer is used. Then, a process of peeling the semiconductor substrate is performed. At this time, the adhesive layer or the pressure-sensitive adhesive layer of the support substrate may remain on the substrate as foreign matter (residue). This occurs particularly noticeably when an adhesive layer is formed directly on the surface of a semiconductor substrate on which wiring or the like has already been formed, or when a support substrate having a pressure-sensitive adhesive layer is directly attached. This foreign matter may not be completely removed even by cleaning with known organic solvents, liquid chemicals, etc.

[0006] Therefore, there is a demand for a simple method for preventing peeling residues generated from adhesive layers, pressure-sensitive adhesive layers, etc. from remaining on semiconductor substrates. For this purpose, when a film (foreign matter removal coating film) is used, the film is required to be easily removable from the semiconductor substrate after the step of peeling the semiconductor substrate is performed (easy removability).

[0007] An object of the present invention is to provide a coating film-forming composition for removing foreign matter, which can provide a coating film for removing foreign matter that is easily removable, and a method for producing a coating film for removing foreign matter, a semiconductor substrate, and a processed semiconductor substrate using the composition.

[0008] The present inventors have conducted extensive research to solve the above problems, and as a result have found that the above problems can be solved, and have completed the present invention having the following gist. That is, the present invention includes the following: [1] A coating film-forming composition for removing foreign matter, which contains a polymer and a solvent and is capable of forming a coating film that can be removed with a removal liquid, wherein the polymer is —O—C(═O)—(O) ｍ The composition is a polymer containing a structural unit (A) having a ring structure containing a - group (m represents 0 or 1). [2] The composition according to [1], wherein the structural unit (A) is a structural unit represented by the following formula (A-1): [In formula (A-1), R １ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms; X １ represents an ester group or an amide group. １represents a single bond or an alkylene group having 1 to 6 carbon atoms. Q is a cyclic structure (r) having 3 to 10 carbon atoms and containing a lactone ring or a carbonate ring, which may be substituted. The cyclic structure (r) may be polycyclic.] [3] The composition according to [1] or [2], wherein the polymer further contains a structural unit (B) having a hydroxy group, a carboxy group, an imide group, or a compound in which a protecting group has been introduced into a hydroxy group or a carboxy group. [4] The composition according to any of [1] to [3], wherein the removal liquid is an alkaline removal liquid. [5] The composition according to any of [1] to [4], which contains at least one of a crosslinking agent and an additive. [6] A coating film for removing foreign matter formed from the composition according to any of [1] to [5]. [7] A semiconductor substrate having a coating film for removing foreign matter according to [6]. [8] A method for manufacturing a processed semiconductor substrate, comprising: a first step of bonding the semiconductor substrate described in [7] and a support substrate via the foreign matter removal coating film to manufacture a laminate; a second step of processing the laminate; a third step of peeling the support substrate from the laminate; and a fourth step of washing the semiconductor substrate or the support substrate with a remover to remove the foreign matter removal coating film. [9] A method for manufacturing a processed semiconductor substrate described in [8], in which the fourth step removes foreign matter together with the foreign matter removal coating film.

[10] A method for manufacturing a processed semiconductor substrate described in [8] or [9], in which the first step is a step of bonding the semiconductor substrate and the support substrate via the foreign matter removal coating film and adhesive layer to manufacture a laminate.

[11] A method for manufacturing a semiconductor substrate described in

[10] , in which the fourth step removes foreign matter, which is a peeled residue of the adhesive layer, together with the foreign matter removal coating film.

[12] The method for manufacturing a processed semiconductor substrate according to any one of [8] to

[11] , wherein the processing includes connecting the semiconductor substrate and a second semiconductor substrate.

[0009] According to the present invention, it is possible to provide a coating film-forming composition for removing foreign matter, which can provide a coating film for removing foreign matter that is easily removable, as well as a method for producing a coating film for removing foreign matter, a semiconductor substrate, and a processed semiconductor substrate using the composition.

[0010] FIG. 1A is a schematic cross-sectional view (part 1) illustrating an example of a method for manufacturing a processed semiconductor substrate. FIG. 1B is a schematic cross-sectional view (part 2) illustrating an example of a method for manufacturing a processed semiconductor substrate. FIG. 1C is a schematic cross-sectional view (part 3) illustrating an example of a method for manufacturing a processed semiconductor substrate. FIG. 1D is a schematic cross-sectional view (part 4) illustrating an example of a method for manufacturing a processed semiconductor substrate. FIG. 1E is a schematic cross-sectional view (part 5) illustrating an example of a method for manufacturing a processed semiconductor substrate. FIG. 1F is a schematic cross-sectional view (part 6) illustrating an example of a method for manufacturing a processed semiconductor substrate. FIG. 1G is a schematic cross-sectional view (part 7) illustrating an example of a method for manufacturing a processed semiconductor substrate. FIG. 2A is a schematic cross-sectional view (part 1) illustrating another example of a method for manufacturing a processed semiconductor substrate. FIG. 2B is a schematic cross-sectional view (part 2) illustrating another example of a method for manufacturing a processed semiconductor substrate. FIG. 2C is a schematic cross-sectional view (part 3) illustrating another example of a method for manufacturing a processed semiconductor substrate. FIG. 2D is a schematic cross-sectional view (part 4) illustrating another example of a method for manufacturing a processed semiconductor substrate. FIG. 2E is a schematic cross-sectional view (part 5) illustrating another example of a method for manufacturing a processed semiconductor substrate. Figure 2F is a schematic cross-sectional view (No. 6) for explaining another example of a method for manufacturing a processed semiconductor substrate. Figure 2G is a schematic cross-sectional view (No. 7) for explaining another example of a method for manufacturing a processed semiconductor substrate. Figure 2H is a schematic cross-sectional view (No. 8) for explaining another example of a method for manufacturing a processed semiconductor substrate. Figure 2I is a schematic cross-sectional view (No. 9) for explaining another example of a method for manufacturing a processed semiconductor substrate. Figure 2J is a schematic cross-sectional view (No. 10) for explaining another example of a method for manufacturing a processed semiconductor substrate. Figure 2K is a schematic cross-sectional view (No. 11) for explaining another example of a method for manufacturing a processed semiconductor substrate.

[0011] (Coating Film-Forming Composition for Removing Foreign Matter) The coating film-forming composition for removing foreign matter of the present invention contains a polymer and a solvent. The coating film-forming composition for removing foreign matter is preferably capable of forming a coating film that can be removed by a removal liquid.

[0012] <Polymer> The polymer is —O—C(═O)—(O) ｍ The polymer includes a structural unit (A) having a ring structure containing a - group (m represents 0 or 1). Examples of the ring structure include a lactone ring and a carbonate ring.

[0013] A coating film-forming composition for removing foreign matter containing a polymer containing the structural unit (A) can easily produce a coating film for removing foreign matter that is easily removable. This is because the ring structure, when hydrolyzed, becomes a structure that has a carboxyl group and a hydroxyl group and is easily soluble in an alkaline solvent. Furthermore, a coating film-forming composition for removing foreign matter containing a polymer containing the structural unit (A) tends to have good applicability (leveling ability) when forming a coating film.

[0014] The structural unit (A) is a structural unit represented by the following formula (A-1). [In formula (A-1), R １ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms; X １ represents an ester group or an amide group. １ represents a single bond or an alkylene group having 1 to 6 carbon atoms. Q represents an optionally substituted ring structure (r) having 3 to 10 carbon atoms and containing a lactone ring or a carbonate ring. The ring structure (r) may be polycyclic.]

[0015] R １ Examples of the alkyl group having 1 to 3 carbon atoms include a methyl group, an ethyl group, and a propyl group.

[0016] Y １Examples of the alkylene group having 1 to 6 carbon atoms in the formula (I) include a methylene group, an ethylene group, an n-propylene group, an isopropylene group, a cyclopropylene group, an n-butylene group, an isobutylene group, an s-butylene group, a t-butylene group, a cyclobutylene group, a 1-methyl-cyclopropylene group, a 2-methyl-cyclopropylene group, an n-pentylene group, a 1-methyl-n-butylene group, a 2-methyl-n-butylene group, a 3-methyl-n-butylene group, a 1,1-dimethyl-n-propylene group, a 1,2-dimethyl-n-propylene group, a 2,2-dimethyl-n-propylene group, and a 1-ethyl -n-propylene group, cyclopentylene group, 1-methyl-cyclobutylene group, 2-methyl-cyclobutylene group, 3-methyl-cyclobutylene group, 1,2-dimethyl-cyclopropylene group, 2,3-dimethyl-cyclopropylene group, 1-ethyl-cyclopropylene group, 2-ethyl-cyclopropylene group, n-hexylene group, 1-methyl-n-pentylene group, 2-methyl-n-pentylene group, 3-methyl-n-pentylene group, 4-methyl-n-pentylene group, 1,1-dimethyl-n-butylene group, 1,2-dimethyl-n-butylene group, 1,3-dimethyl-n-butylene group ethylene group, 2,2-dimethyl-n-butylene group, 2,3-dimethyl-n-butylene group, 3,3-dimethyl-n-butylene group, 1-ethyl-n-butylene group, 2-ethyl-n-butylene group, 1,1,2-trimethyl-n-propylene group, 1,2,2-trimethyl-n-propylene group, 1-ethyl-1-methyl-n-propylene group, 1-ethyl-2-methyl-n-propylene group, cyclohexylene group, 1-methyl-cyclopentylene group, 2-methyl-cyclopentylene group, 3-methyl-cyclopentylene group, 1-ethyl-cyclobutylene group, 2-ethyl-cyclo butylene group, 3-ethyl-cyclobutylene group, 1,2-dimethyl-cyclobutylene group, 1,3-dimethyl-cyclobutylene group, 2,2-dimethyl-cyclobutylene group, 2,3-dimethyl-cyclobutylene group, 2,4-dimethyl-cyclobutylene group, 3,3-dimethyl-cyclobutylene group, 1-n-propyl-cyclopropylene group, 2-n-propyl-cyclopropylene group, 1-isopropyl-cyclopropylene group, 2-isopropyl-cyclopropylene group, 1,2,2-trimethyl-cyclopropylene group, 1,2,3-trimethyl-cyclopropylene group, 2,Examples of the cyclopropylene group include a 2,3-trimethyl-cyclopropylene group, a 1-ethyl-2-methyl-cyclopropylene group, a 2-ethyl-1-methyl-cyclopropylene group, a 2-ethyl-2-methyl-cyclopropylene group, and a 2-ethyl-3-methyl-cyclopropylene group.

[0017] The ring structure (r) represented by Q may be, for example, a structure represented by the following formula (Q-1). [In formula (Q-1), R ２ represents an optionally substituted hydrocarbon group having 1 to 7 carbon atoms. １ represents a single bond or an oxygen atom, provided that —O—C(═O)—Z １ The monocyclic structure containing the - group is a 3- to 7-membered ring. ２ may form a ring connected to the monocyclic structure. １ represents the bond that bonds to

[0018] R ２ The optionally substituted hydrocarbon group having 1 to 7 carbon atoms in R is, for example, a hydrocarbon group having 1 to 7 carbon atoms. ２ does not form a ring connected to the monocyclic structure ２ The number of carbon atoms in R is, for example, 1 to 4. ２ R when forming a ring connected to a monocyclic structure ２ The number of carbon atoms is, for example, 3 to 7. Examples of the substituent in the optionally substituted hydrocarbon group having 1 to 7 carbon atoms include a hydrogen atom, a hydroxyl group, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, an ester group, a carboxylic acid group, an ether group, a hydroxyl group, a sulfonic acid group, a carbonyl group, and an amino group.

[0019] In formula (Q-1), —O—C(═O)—Z １ The monocyclic structure containing a - group is a 3- to 7-membered ring, and preferably a 5- or 6-membered ring.

[0020] R ２ may form a ring linked to the monocyclic structure (corresponding to the case where the ring structure (r) in formula (A-1) is a polycyclic ring). ２ is represented by, for example, the following formula (M): [In formula (M), *1 represents Y １ (where Y １ When is a single bond, *1 is X １ *2 represents a bond bonded to an oxygen atom. *3 represents a bond bonded to Z １ (where Z １ is a single bond, *3 represents a bond to the carbon atom in —O—C(═O)—.

[0021] Examples of the structural unit represented by formula (A-1) include structural units represented by the following formulae (A-1-1) to (A-1-10). １ , X １ , and Y １ In formulas (A-1-1) to (A-1-3), (A-1-5) to (A-1-7), and (A-1-9) to (A-1-10), Z in formula (A-1) １ In formula (A-1-4) and formula (A-1-8), Z in formula (A-1) is a single bond. １ is an oxygen atom. Formulas (A-1-9) to (A-1-10) are used when the ring structure (r) in formula (A-1) is polycyclic, and when R in formula (Q-1) is ２ is a structural unit in which a ring is formed by linking to a monocyclic structure.

[0022] X in formula (A-1) and formulas (A-1-1) to (A-1-10) １ As R, an ester group is preferred. １ is preferably a hydrogen atom or a methyl group.

[0023] The polymer may further include the following structural unit (B): The structural unit (B) has a hydroxy group, a carboxy group, an imide group, or a compound in which a protecting group has been introduced into a hydroxy group or a carboxy group.

[0024] Examples of the structural unit (B) include those having a structural unit derived from a (meth)acrylic acid ester compound, a (meth)acrylamide compound, or a styrene compound. Note that the structural unit (B) is different from the structural unit (A). In the present invention, the (meth)acrylic acid ester compound means an acrylic acid ester compound or a methacrylic acid ester compound. The same applies to a (meth)acrylamide compound.

[0025] Examples of structural units derived from (meth)acrylic ester compounds include structural units represented by the following formula (2-1): Examples of structural units derived from (meth)acrylamide compounds include structural units represented by the following formula (2-2): Examples of structural units derived from styrene compounds include structural units represented by the following formula (2-3): [In formulas (2-1) to (2-3), R １１ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R １２ represents a monovalent group having 1 to 20 carbon atoms. １３ represents a hydrogen atom or a monovalent group having 1 to 20 carbon atoms. １４ each independently represents a halogen atom, a hydroxy group, a carboxy group, a cyano group, a nitro group, or a monovalent group having 1 to 10 carbon atoms, and m represents an integer of 0 to 5.

[0026] R １２ and R １３ The number of carbon atoms in may be 1 to 20, or may be 1 to 10. １２ and R １３ The monovalent group having 1 to 20 carbon atoms in R may have a heteroatom. Examples of the heteroatom include an oxygen atom and a nitrogen atom. １２ and R １３ The monovalent group having 1 to 20 carbon atoms in R may have an aromatic ring. Examples of the aromatic ring include an aromatic hydrocarbon ring and an aromatic heterocyclic ring. Examples of the aromatic hydrocarbon ring include a benzene ring and a naphthalene ring. １２ and R １３The monovalent group having 1 to 20 carbon atoms in R may have, for example, a halogen atom, a hydroxy group, a carboxy group, a cyano group, a nitro group, an epoxy group, or the like. １２ and R １３ In the above formula, examples of the monovalent group having 1 to 20 carbon atoms include an optionally substituted alkyl group and an optionally substituted aromatic group. Examples of the substituent in the optionally substituted alkyl group include a halogen atom, a hydroxy group, a carboxy group, a cyano group, a nitro group, an epoxy group, and an optionally substituted aromatic group. Examples of the substituent in the optionally substituted aromatic group include a halogen atom, a hydroxy group, a carboxy group, a cyano group, a nitro group, an epoxy group, an alkyl group having 1 to 6 carbon atoms which may be substituted with a halogen atom, and an alkoxy group having 1 to 6 carbon atoms which may be substituted with a halogen atom. Examples of the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group, and a butyl group. Examples of the alkoxy group having 1 to 6 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, and a butoxy group.

[0027] R １４ The monovalent group having 1 to 10 carbon atoms in R may have a heteroatom. Examples of the heteroatom include an oxygen atom and a nitrogen atom. １４ The monovalent group having 1 to 10 carbon atoms in R may have, for example, a halogen atom, a hydroxy group, a carboxy group, a cyano group, a nitro group, an epoxy group, or the like. １４ In the formula (I), examples of the monovalent group having 1 to 10 carbon atoms include an alkyl group having 1 to 6 carbon atoms which may be substituted with a halogen atom, and an alkoxy group having 1 to 6 carbon atoms which may be substituted with a halogen atom. Examples of the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group, and a butyl group. Examples of the alkoxy group having 1 to 6 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, and a butoxy group.

[0028] Specific examples of the acrylic acid ester compound include methyl acrylate, ethyl acrylate, normal hexyl acrylate, i-propyl acrylate, cyclohexyl acrylate, benzyl acrylate, phenyl acrylate, 4-hydroxyphenyl acrylate, anthrylmethyl acrylate, 2,2,2-trifluoroethyl acrylate, 2,2,2-trichloroethyl acrylate, 2-bromoethyl acrylate, 2-methoxyethyl acrylate, tetrahydrofurfuryl acrylate, 2-methyl-2-adamantyl acrylate, 3-acryloxypropyltriethoxysilane, and glycidyl acrylate, but are not limited to these.

[0029] Specific examples of methacrylic acid ester compounds include methyl methacrylate, ethyl methacrylate, normal hexyl methacrylate, i-propyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, phenyl methacrylate, 4-hydroxyphenyl acrylate, anthrylmethyl methacrylate, 2,2,2-trifluoroethyl methacrylate, 2,2,2-trichloroethyl methacrylate, 2-bromoethyl methacrylate, 2-methoxyethyl methacrylate, tetrahydrofurfuryl methacrylate, 2-methyl-2-adamantyl methacrylate, 3-methacryloxypropyltriethoxysilane, glycidyl methacrylate, 2-phenylethyl methacrylate, bromophenyl methacrylate, and the like, but are not limited to these.

[0030] Specific examples of the acrylamide compound include, but are not limited to, acrylamide, N-methylacrylamide, N-ethylacrylamide, N-benzylacrylamide, N-phenylacrylamide, N-(4-hydroxyphenyl)acrylamide, N,N-dimethylacrylamide, and N-anthrylacrylamide.

[0031] Specific examples of methacrylamide compounds include methacrylamide, N-methylmethacrylamide, N-ethylmethacrylamide, N-benzylmethacrylamide, N-phenylmethacrylamide, N-(4-hydroxyphenyl)methacrylamide, N,N-dimethylmethacrylamide, and N-anthrylmethacrylamide, but are not limited to these.

[0032] Specific examples of styrene compounds include, but are not limited to, styrene, chlorostyrene, bromostyrene, methoxystyrene, cyanostyrene, and acetylstyrene.

[0033] The polymer may have structural units other than the structural units (A) and (B). Examples of monomers that derive such structural units include, but are not limited to, acrylic acid, methacrylic acid, vinyl compounds, maleimide compounds, maleic anhydride, and acrylonitrile.

[0034] Specific examples of vinyl compounds include, but are not limited to, vinyl alcohol, 2-hydroxyethyl vinyl ether, methyl vinyl ether, ethyl vinyl ether, benzyl vinyl ether, vinyl acetate, vinyltrimethoxysilane, 2-chloroethyl vinyl ether, 2-methoxyethyl vinyl ether, vinylnaphthalene, and vinylanthracene.

[0035] Examples of maleimide compounds include, but are not limited to, maleimide, N-methylmaleimide, N-phenylmaleimide, N-cyclohexylmaleimide, N-benzylmaleimide, and N-hydroxyethylmaleimide.

[0036] The lower limit of the molar ratio of the structural unit represented by formula (A) to all structural units of the polymer is not particularly limited, but from the viewpoint of preferably obtaining the effects of the present invention, the molar ratio of the structural unit represented by formula (A) is preferably 5 mol% or more, more preferably 10 mol% or more, and particularly preferably 20 mol% or more. The upper limit of the molar ratio of the structural unit represented by formula (A) to all structural units of the polymer is not particularly limited, but from the viewpoint of preferably obtaining the effects of the present invention, the molar ratio of the structural unit represented by formula (A) is preferably 90 mol% or less, more preferably 75 mol% or less, and particularly preferably 50 mol% or less.

[0037] The lower limit of the molar ratio of the structural unit represented by formula (B) to all structural units of the polymer is not particularly limited, but from the viewpoint of preferably obtaining the effects of the present invention, the molar ratio of the structural unit represented by formula (B) is preferably 10 mol% or more, more preferably 25 mol% or more, and particularly preferably 50 mol% or more. The upper limit of the molar ratio of the structural unit represented by formula (B) to all structural units of the polymer is not particularly limited, but from the viewpoint of preferably obtaining the effects of the present invention, the molar ratio of the structural unit represented by formula (B) is preferably 95 mol% or less, more preferably 90 mol% or less, and particularly preferably 80 mol% or less.

[0038] The polymer may be a homopolymer or a copolymer, and if the polymer is a copolymer, it may be a random copolymer or a block copolymer.

[0039] The method for producing the polymer is not particularly limited. The polymer can be produced by polymerizing the monomer by a conventional method, for example, bulk polymerization, solution polymerization, suspension polymerization, or emulsion polymerization. Solution polymerization is particularly preferred, and in this case, for example, the monomer can be polymerized using a polymerization initiator. As the polymerization initiator, an organic peroxide or a diazo compound can be used.

[0040] Examples of organic peroxides include diacyl peroxides, peroxydicarbonates, peroxyesters, and peroxysulfonates. Examples of diacyl peroxides include diacetyl peroxide, diisobutyl peroxide, didecanoyl peroxide, benzoyl peroxide, and succinic acid peroxide. Examples of peroxydicarbonates include diisopropyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, and diallyl peroxydicarbonate. Examples of peroxyesters include tert-butyl peroxyisobutyrate, tert-butyl neodecanoate, and cumene peroxyneodecanate. Examples of peroxysulfonates include acetylcyclohexylsulfonyl peroxide.

[0041] Examples of diazo compounds include 2,2'-azobisisobutyronitrile, 2,2'-azobis(dimethylisobutyrate), 4,4'-azobis(4-cyanovaleric acid), 2,2'-azobis(4-methoxy-2,4-dimethoxyvaleronitrile), and 2,2'-azobis(2-cyclopropylpropionitrile).

[0042] When it is desired to complete the polymerization in a short time, it is preferable to use a polymerization initiator having a decomposition half-life of 10 hours or less at 80° C. As such a polymerization initiator, benzoyl peroxide and 2,2′-azobisisobutyronitrile are preferred, and 2,2′-azobisisobutyronitrile is more preferred.

[0043] The amount of the polymerization initiator used is, for example, 0.0001 to 0.2 equivalents, and preferably 0.0005 to 0.1 equivalents, based on the total amount of the monomers used.

[0044] The solvent used in the polymerization is not particularly limited as long as it is inert to the polymerization reaction and is compatible with the resulting polymer. Examples of the solvent include aromatic hydrocarbons, alicyclic hydrocarbons, aliphatic hydrocarbons, ketones, ethers, esters, amides, sulfoxides, alcohols, and polyhydric alcohol derivatives. Examples of aromatic hydrocarbons include benzene, toluene, and xylene. Examples of alicyclic hydrocarbons include cyclohexane. Examples of aliphatic hydrocarbons include n-hexane and n-octane. Examples of ketones include acetone, methyl ethyl ketone, and cyclohexanone. Examples of ethers include tetrahydrofuran and dioxane. Examples of esters include ethyl acetate and butyl acetate. Examples of amides include N,N-dimethylformamide and N,N-dimethylacetamide. Examples of sulfoxides include dimethyl sulfoxide. Examples of alcohols include methanol and ethanol. Examples of polyhydric alcohol derivatives include ethylene glycol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, etc. These can be used alone or in combination of two or more.

[0045] The polymerization temperature is not particularly limited as long as it is within a temperature range in which side reactions such as transfer reactions and termination reactions do not occur and the monomer is consumed to complete the polymerization, but it is preferably carried out within a temperature range of -100°C or higher and the boiling point of the solvent or lower. The concentration of the monomer relative to the solvent is not particularly limited, but is usually 1 to 40% by mass, preferably 10 to 30% by mass. The polymerization reaction time can be appropriately selected, but is usually within a range of 2 to 50 hours.

[0046] The weight-average molecular weight of the polymer is not particularly limited, but is preferably 5,000 to 75,000, and more preferably 10,000 to 50,000. The weight-average molecular weight is a value obtained by gel permeation chromatography (GPC) using polystyrene as a standard sample.

[0047] The content of the polymer in the coating film-forming composition for removing foreign matter is not particularly limited, but is preferably 0.01% by mass to 60% by mass, more preferably 0.1% by mass to 40% by mass, and particularly preferably 0.5% by mass to 30% by mass, based on the solid content.

[0048] <<Removal Liquid>> The removal liquid is not particularly limited as long as it can remove a coating film formed from the coating film-forming composition for removing foreign matter. The coating film is formed, for example, on a semiconductor substrate. In this case, "removal" refers to removal from the semiconductor substrate. Here, examples of the removal include dissolution removal and peeling removal. Examples of peeling removal include peeling from the adherend by swelling.

[0049] The removal liquid may contain water or an organic solvent, and may contain 50% by mass or more of an organic solvent.

[0050] Examples of organic solvents include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol propyl ether acetate, toluene, xylene, methyl ethyl ketone, cyclopentanone, cyclohexanone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone.

[0051] Examples of the removal liquid include an alkaline removal liquid and an acid removal liquid.

[0052] The alkaline remover contains an alkali. Examples of alkalis include ammonia, inorganic alkaline compounds, quaternary ammonium hydroxides, amines, and hydrazine. The alkaline remover may be a developer or cleaning solution used in semiconductor manufacturing processes and exhibit alkaline properties. For example, an example of a developer is NMD-3 (a 2.38% aqueous solution of tetramethylammonium hydroxide, manufactured by Tokyo Ohka Kogyo Co., Ltd.). Examples of inorganic alkaline compounds include potassium hydroxide, sodium hydroxide, lithium hydroxide, diammonium hydrogen phosphate, dipotassium hydrogen phosphate, disodium hydrogen phosphate, lithium silicate, sodium silicate, potassium silicate, lithium carbonate, sodium carbonate, potassium carbonate, lithium borate, sodium borate, and potassium borate. Examples of quaternary ammonium hydroxides include tetramethylammonium hydroxide, tetraethylammonium hydroxide, trimethylhydroxyethylammonium hydroxide, and choline. Examples of amines include ethanolamine, methylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, n-propylamine, di-n-propylamine, isopropylamine, diisopropylamine, methyldiethylamine, dimethylethanolamine, triethanolamine, and ethylenediamine. Examples of hydrazines include hydrazine monohydrate. The alkaline removal solution may be SC-1 (ammonia-hydrogen peroxide solution).

[0053] The acidic removal solution contains an acid. Examples of the acid include inorganic acids and organic acids. Examples of the inorganic acids include sulfuric acid, nitric acid, hydrochloric acid, phosphoric acid, and hydrofluoric acid. The acidic removal solution is, for example, an aqueous solution containing dilute hydrofluoric acid. The acidic removal solution may also be, for example, an aqueous solution containing sulfuric acid and hydrogen peroxide, or an aqueous solution containing acetic acid or a chelating agent. Examples of the chelating agent include organic acids, salts of organic acids, amino acids, and amino acid derivatives.

[0054] <Solvent> Examples of the solvent contained in the coating film-forming composition for removing foreign matter include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol propyl ether acetate, toluene, xylene, methyl ethyl ketone, cyclopentanone, Examples of solvents that can be used include cyclohexanone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone. These solvents can be used alone or in combination of two or more. Furthermore, high-boiling point solvents such as propylene glycol monobutyl ether and propylene glycol monobutyl ether acetate can be mixed and used.

[0055] The coating film-forming composition for removing foreign matter can be easily prepared, for example, by uniformly mixing the components, and is used in the form of a solution by dissolving in a suitable solvent. The coating film-forming composition for removing foreign matter prepared in this manner is preferably filtered using a filter with a pore size of about 0.2 μm before use. The coating film-forming composition for removing foreign matter prepared in this manner also has excellent long-term storage stability at room temperature.

[0056] The proportion of solids in the coating film-forming composition for removing foreign matter is not particularly limited as long as each component is uniformly dissolved, but is, for example, 0.5 to 50 mass %, or, for example, 1 to 30 mass %. Here, the solids content is the total components of the coating film-forming composition for removing foreign matter excluding the solvent component.

[0057] In the present invention, foreign matter refers to substances other than the intended object that are attached to a substrate. In semiconductor device manufacturing, foreign matter is an unnecessary substance. Examples of foreign matter include particles attached to a wafer, metal impurities, post-etching residues, peeling residues of an adhesive layer, etc.

[0058] The coating film for removing foreign matter is particularly preferably used in a process in which wafers are bonded together with an adhesive and then the adhesive is peeled off, by forming the coating film of the present invention before applying the adhesive, and then removing foreign matter (residue of the adhesive layer) after the wafer bonding and peeling processes.

[0059] The coating film for removing foreign matter can also be used to remove foreign matter that is already present on the semiconductor substrate.

[0060] The dissolution of a foreign matter-removing coating film in a removal liquid means that, when immersed, washed, or the like in the removal liquid, the coating film dissolves in the removal liquid and disappears from the substrate or other adherend. Dissolution in the present invention means that the film formed on the substrate is removed, for example, by at least 90% or more of the initial thickness (i.e., the remaining film thickness is 10% or less of the initial thickness), or by at least 95% or more (i.e., the remaining film thickness is 5% or less of the initial thickness), or by at least 99% or more (i.e., the remaining film thickness is 1% or less of the initial thickness), and most preferably by 100% (i.e., the remaining film thickness is 0% of the initial thickness (no remaining film)).

[0061] The composition preferably contains at least one of a crosslinking agent and an additive.

[0062] <Crosslinking Agent> The crosslinking agent is not particularly limited and has a structure different from that of the polymer.

[0063] Preferred crosslinking agents are aminoplast crosslinking agents and phenoplast crosslinking agents. Aminoplast crosslinking agents are addition condensation products of a compound having an amino group, such as melamine or guanamine, with formaldehyde. Phenoplast crosslinking agents are addition condensation products of a compound having a phenolic hydroxy group with formaldehyde.

[0064] Examples of the crosslinking agent include compounds having two or more of the following structures: (In the structure, R １０１ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an alkoxyalkyl group having 2 to 6 carbon atoms. * represents a bond.) The bond is bonded to, for example, a nitrogen atom or a carbon atom constituting an aromatic hydrocarbon ring.

[0065] R １０１ is preferably a hydrogen atom, a methyl group, an ethyl group or a group represented by the following structure. (In the structure, R １０２ represents a hydrogen atom, a methyl group, or an ethyl group. * represents a bond.

[0066] As the crosslinking agent, a melamine compound, a guanamine compound, a glycoluril compound, a urea compound, or a compound having a phenolic hydroxy group is preferred. These may be used alone or in combination of two or more.

[0067] Examples of the melamine compound include hexamethylol melamine, hexamethoxymethyl melamine, a compound in which 1 to 6 methylol groups of hexamethylol melamine have been methoxymethylated, or a mixture thereof, hexamethoxyethyl melamine, hexaacyloxymethyl melamine, a compound in which 1 to 6 methylol groups of hexamethylol melamine have been acyloxymethylated, or a mixture thereof.

[0068] Examples of the guanamine compound include tetramethylolguanamine, tetramethoxymethylguanamine, a compound in which one to four methylol groups of tetramethylolguanamine are methoxymethylated, or a mixture thereof; tetramethoxyethylguanamine, tetraacyloxyguanamine, a compound in which one to four methylol groups of tetramethylolguanamine are acyloxymethylated, or a mixture thereof; and the like.

[0069] Examples of glycoluril compounds include tetramethylol glycoluril, tetramethoxy glycoluril, tetramethoxymethyl glycoluril, compounds in which one to four methylol groups of tetramethylol glycoluril are methoxymethylated or mixtures thereof, and compounds in which one to four methylol groups of tetramethylol glycoluril are acyloxymethylated or mixtures thereof.

[0070] The glycoluril compound may be, for example, a glycoluril derivative represented by the following formula (1E). (In formula (1E), four R １ each independently represents a methyl group or an ethyl group, R ２ and R ３ each independently represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group.

[0071] Examples of the glycoluril derivative represented by the formula (1E) include compounds represented by the following formulas (1E-1) to (1E-6).

[0072] The glycoluril derivative represented by formula (1E) can be obtained, for example, by reacting a glycoluril derivative represented by the following formula (2E) with at least one compound represented by the following formula (3d).

[0073] (In formula (2E), R ２ and R ３ each independently represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group; R ４ each independently represents an alkyl group having 1 to 4 carbon atoms.

[0074] (In formula (3d), R １ represents a methyl group or an ethyl group.)

[0075] Examples of glycoluril derivatives represented by formula (2E) include compounds represented by formulas (2E-1) to (2E-4) below. Furthermore, examples of compounds represented by formula (3d) include compounds represented by formulas (3d-1) and (3d-2) below.

[0076] Examples of the urea compound include tetramethylol urea, tetramethoxymethyl urea, tetramethylol urea compounds in which one to four methylol groups are methoxymethylated, or mixtures thereof, and tetramethoxyethyl urea.

[0077] Examples of the compound having a phenolic hydroxy group include compounds represented by the following formula (G-1) or (G-2). (In formula (G-1) and formula (G-2), Q １ represents a single bond or a monovalent organic group. １ and R ４ R represents an alkyl group having 2 to 10 carbon atoms, or an alkyl group having 2 to 10 carbon atoms and an alkoxy group having 1 to 10 carbon atoms. ２ and R ５ R represents a hydrogen atom or a methyl group. ３ and R ６ n represents an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 40 carbon atoms. １ is 1≦n １ an integer ≦3, n ２ is 2≦n ２ n is an integer ≦5 ３ is 0≦n ３ an integer ≦3, n ４ is 0≦n ４ an integer ≦3, 3≦(n １ +n ２ +n ３ +n ４ ) represents an integer ≦6. ５ is 1≦n ５ an integer ≦3, n ６ is 1≦n ６ n is an integer ≦4 ７ is 0≦n ７ an integer ≦3, n８ is 0≦n ８ an integer ≦3, 2≦(n ５ +n ６ +n ７ +n ８ ) represents an integer of ≦5. m1 represents an integer of 2 to 10.

[0078] Examples of compounds having a phenolic hydroxy group include compounds represented by the following formula (G-3) or formula (G-4): The compound represented by formula (G-1) or formula (G-2) may be obtained by reacting a compound represented by the following formula (G-3) or formula (G-4) with a hydroxyl group-containing ether compound or an alcohol having 2 to 10 carbon atoms. (In formula (G-3) and formula (G-4), Q ２ represents a single bond or a divalent organic group. ８ , R ９ , R １１ and R １２ R represents a hydrogen atom or a methyl group. ７ and R １０ n represents an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 40 carbon atoms. ９ is 1≦n ９ an integer ≦3, n １０ is 2≦n １０ n is an integer ≦5 １１ is 0≦n １１ an integer ≦3, n １２ is 0≦n １２ an integer ≦3, 3≦(n ９ +n １０ +n １１ +n １２ ) represents an integer ≦6. １３ is 1≦n １３ an integer ≦3, n １４ is 1≦n １４ n is an integer ≦4 １５ is 0≦n １５ an integer ≦3, n １６ is 0≦n １６ an integer ≦3, 2≦(n １３ +n １４ +n １５ +n １６) represents an integer of ≦5. m2 represents an integer of 2 to 10. ２ In the above, the m2-valent organic group includes, for example, an m2-valent organic group having 1 to 4 carbon atoms.

[0079] Examples of the compound represented by formula (G-1) or formula (G-2) include the following compounds:

[0080] Examples of the compound represented by formula (G-3) or formula (G-4) include the following compounds: The above compound is available as a product of Asahi Organic Chemicals Co., Ltd. and Honshu Chemical Industry Co., Ltd. An example of the product is TMOM-BP, a product name of Asahi Organic Chemicals Co., Ltd.

[0081] Among these, glycoluril compounds are preferred, specifically tetramethylol glycoluril, tetramethoxy glycoluril, tetramethoxymethyl glycoluril, tetramethylol glycoluril compounds in which one to four methylol groups have been methoxymethylated or mixtures thereof, and tetramethylol glycoluril compounds in which one to four methylol groups have been acyloxymethylated or mixtures thereof, with tetramethoxymethyl glycoluril being more preferred.

[0082] The molecular weight of the crosslinking agent is not particularly limited, but is preferably 500 or less.

[0083] The content of the crosslinking agent is, for example, 5 to 70 parts by mass, or 5 to 60 parts by mass, and preferably 5 to 45 parts by mass, relative to 100 parts by mass of the polymer. From the viewpoints of the degree of curing of the coating film and preventing intermixing with the adhesive layer, the content of the crosslinking agent is preferably 5 parts by mass or more relative to 100 parts by mass of the polymer, and from the viewpoint of solubility in the removal liquid, the content of the crosslinking agent is preferably 70 parts by mass or less relative to 100 parts by mass of the polymer.

[0084] <Additives> The coating film-forming composition for removing foreign matter may contain, as additives, a curing catalyst, a light-absorbing compound, a surfactant, an adhesion aid, a rheology modifier, and silica particles.

[0085] The curing catalyst may be either a thermal acid generator or a photoacid generator, but it is preferable to use a thermal acid generator. Examples of the thermal acid generator include sulfonic acid compounds and carboxylic acid compounds such as p-toluenesulfonic acid, trifluoromethanesulfonic acid, pyridinium p-toluenesulfonate (pyridinium p-toluenesulfonic acid), pyridinium phenolsulfonic acid, pyridinium p-hydroxybenzenesulfonic acid (pyridinium p-phenolsulfonate salt), pyridinium trifluoromethanesulfonic acid, salicylic acid, camphorsulfonic acid, 5-sulfosalicylic acid, 4-chlorobenzenesulfonic acid, 4-hydroxybenzenesulfonic acid, benzenedisulfonic acid, 1-naphthalenesulfonic acid, citric acid, benzoic acid, hydroxybenzoic acid, N-methylmorpholine p-toluenesulfonic acid, N-methylmorpholine p-hydroxybenzenesulfonic acid, and N-methylmorpholine-5-sulfosalicylic acid.

[0086] Examples of the photoacid generator include an onium salt compound, a sulfonimide compound, and a disulfonyldiazomethane compound.

[0087] Examples of the onium salt compound include iodonium salt compounds such as diphenyliodonium hexafluorophosphate, diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoro-normal butanesulfonate, diphenyliodonium perfluoro-normal octanesulfonate, diphenyliodonium camphorsulfonate, bis(4-tert-butylphenyl)iodonium camphorsulfonate, and bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate; and sulfonium salt compounds such as triphenylsulfonium hexafluoroantimonate, triphenylsulfonium nonafluoro-normal butanesulfonate, triphenylsulfonium camphorsulfonate, and triphenylsulfonium trifluoromethanesulfonate.

[0088] Examples of the sulfonimide compound include N-(trifluoromethanesulfonyloxy)succinimide, N-(nonafluoronormalbutanesulfonyloxy)succinimide, N-(camphorsulfonyloxy)succinimide, and N-(trifluoromethanesulfonyloxy)naphthalimide.

[0089] Examples of the disulfonyldiazomethane compound include bis(trifluoromethylsulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, bis(phenylsulfonyl)diazomethane, bis(p-toluenesulfonyl)diazomethane, bis(2,4-dimethylbenzenesulfonyl)diazomethane, and methylsulfonyl-p-toluenesulfonyldiazomethane.

[0090] The curing catalyst may be used alone or in combination of two or more.

[0091] When a curing catalyst is used, the content of the curing catalyst is, for example, 0.1% by mass to 50% by mass, and preferably 1% by mass to 30% by mass, relative to the crosslinking agent.

[0092] The light-absorbing compound is not particularly limited as long as it has absorption at the exposure wavelength to be used. Compounds having an aromatic ring structure such as an anthracene ring, a naphthalene ring, a benzene ring, a quinoline ring, or a triazine ring are preferably used. Furthermore, from the viewpoint of not inhibiting the solubility of the foreign matter removal coating film in the removal solution, compounds having a phenolic hydroxy group, a carboxyl group, or a sulfonic acid group are preferably used.

[0093] Examples of light-absorbing compounds that have a large absorption for light with a wavelength of 248 nm include 1-naphthalenecarboxylic acid, 2-naphthalenecarboxylic acid, 1-naphthol, 2-naphthol, 1-aminonaphthalene, 1-hydroxy-2-naphthalenecarboxylic acid, 3-hydroxy-2-naphthalenecarboxylic acid, 3,7-dihydroxy-2-naphthalenecarboxylic acid, 6-bromo-2-hydroxynaphthalene, 1,2-naphthalenedicarboxylic acid, 1,3-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, and 1,5-naphthalenedicarboxylic acid. carboxylic acid, 1,6-naphthalenedicarboxylic acid, 1,7-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 1,8-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene Hydroxynaphthalene, 6-hydroxy-1-naphthalenecarboxylic acid, 1-hydroxy-2-naphthalenecarboxylic acid, 3-hydroxy-2-naphthalenecarboxylic acid, 6-hydroxy-2-naphthalenecarboxylic acid, 1-bromo-2-hydroxy-3-naphthalenecarboxylic acid, 1-bromo-4-hydroxy-3-naphthalenecarboxylic acid, 1,6-dibromo-2-hydroxy-3-naphthalenecarboxylic acid, 3-hydroxy-7-methoxy-2-naphthalenecarboxylic acid, 1-amino-2-naphthol, 1,5-dimercaptonaphthalene ethylene, 1,4,5,8-naphthalenetetracarboxylic acid, 3,5-dihydroxy-2-naphthalenecarboxylic acid, 1,4-dihydroxy-2-naphthalenecarboxylic acid, 2-ethoxy-1-naphthalenecarboxylic acid, 2,6-dichloro-1-naphthol, 2-hydroxy-3-naphthalenecarboxylic acid methyl ester, 6-hydroxy-2-naphthalenecarboxylic acid methyl ester, 3-hydroxy-7-methoxy-2-naphthalenecarboxylic acid methyl ester, 3,7-dihydroxy-2-naphthalenecarboxylic acid methyl ester, 2,Examples of such an anthracene include 4-dibromo-1-naphthol, 1-bromo-2-naphthol, 2-naphthalenethiol, 4-methoxy-1-naphthol, 6-acetoxy-2-naphthalenecarboxylic acid, 1,6-dibromo-1-naphthol, 2,6-dibromo-1,5-dihydroxynaphthalene, 1-acetyl-2-naphthol, 9-anthracenecarboxylic acid, 1,4,9,10-tetrahydroxyanthracene, and 1,8,9-trihydroxyanthracene.

[0094] Examples of light-absorbing compounds that have a large absorption for light with a wavelength of 193 nm include benzoic acid, 4-methylbenzoic acid, o-phthalic acid, m-phthalic acid, p-phthalic acid, 2-methoxybenzoic acid, isophthalic acid, terephthalic acid, 2-hydroxybenzoic acid, 3-hydroxybenzoic acid, 4-hydroxybenzoic acid, 2-acetoxybenzoic acid, 2-aminobenzoic acid, 3-aminobenzoic acid, 4-aminobenzoic acid, trimesic acid, 1,4-benzenedicarboxylic acid, 2,3-dimethoxybenzoic acid, 2,4-dimethoxybenzoic acid, 2,5-dimethoxybenzoic acid, 2,4-dihydroxybenzoic acid, 2,6-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, 4-acetylbenzoic acid, pyrrole, and the like. Examples of light-absorbing compounds include lithic acid, trimesic anhydride, 2-s[bis-(4-hydroxyphenyl)-methyl]benzoic acid, 3,4,5-trihydroxybenzoic acid, 2-benzophenonecarboxylic acid, m-phenylbenzoic acid, 3-(4'-hydroxyphenoxy)benzoic acid, 3-phenoxybenzoic acid, phenol, 1,4-dihydroxybenzene, 1,3-dihydroxybenzene, 1,2-dihydroxybenzene, 2-methylphenol, 3-methylphenol, 4-methylphenol, 1,3,5-trihydroxybenzene, 2,2-bis-4-hydroxyphenylpropane, 2-hydroxybiphenyl, 2-aminophenol, 3-aminophenol, 4-aminophenol, and 4-benzyloxyphenol. These light-absorbing compounds can be used by reacting them with a polymer or a compound having one or more reactive groups to suppress sublimation during baking to form a coating film for removing foreign matter.

[0095] For example, in the case of a light-absorbing compound having a carboxyl group or a phenolic hydroxy group, compounds obtained by reacting with a polyfunctional epoxy compound such as tris(2,3-epoxypropyl)isocyanurate, 1,4-butanediol diglycidyl ether, 1,2-epoxy-4-(epoxyethyl)cyclohexane, glycerol triglycidyl ether, diethylene glycol diglycidyl ether, 2,6-diglycidylphenyl glycidyl ether, 1,1,3-tris(p-(2,3-epoxypropoxy)phenyl)propane, 1,2-cyclohexanedicarboxylic acid diglycidyl ester, 4,4'-methylenebis(N,N-diglycidylaniline), 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, trimethylolethane triglycidyl ether, bisphenol-A-diglycidyl ether, and pentaerythritol polyglycidyl ether, or a polymer containing a structure having an epoxy group such as glycidyl methacrylate, can be used.

[0096] The above light-absorbing compounds can be used alone or in combination of two or more. When a light-absorbing compound is used, the content thereof is, for example, 1 to 300 parts by mass, or 1 to 200 parts by mass, or, for example, 1 to 100 parts by mass, or 5 to 100 parts by mass, relative to 100 parts by mass of the polymer. When the content of the light-absorbing compound is 300 parts by mass or less relative to 100 parts by mass of the polymer, the solubility of the foreign matter removal coating film in the removal liquid is excellent, and intermixing of the foreign matter removal coating film with the adhesive layer is less likely to occur.

[0097] A polyhydric phenol compound or a carboxyl group-containing compound can be added to the coating film-forming composition for removing foreign matter in order to accelerate the dissolution rate in the removal solution. Such compounds are not particularly limited, but examples thereof include tris-hydroxyphenylethane, bisphenol-A, bisphenol-S, 4,4'-isopropylidene-di-o-cresol, 5-tert-butylpyrogallol, hexafluorobisphenol-A, 3,3,3',3'-tetramethyl-1,1'-spirobisindane-5,5',6,6'-tetrol, 4,4'-(9-fluorenylidene)diphenol, bisphenol polyhydric phenols such as benzophenone-1, benzoyl-4-hydroxybenzoates ... Examples of suitable polycarboxylic acids include hydroxyphthalic acid, 3,4-dihydroxyphthalic acid, 4,5-dihydroxyphthalic acid, 3,3'-, 4,4'-biphenyltetracarboxylic acid, 3,3'-, 4,4'-benzophenonetetracarboxylic acid, 3,3'-, 4,4'-diphenylethertetracarboxylic acid, 3,3'-, 4,4'-diphenylsulfonetetracarboxylic acid, 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid, 1,2,3,4-cyclohexanetetracarboxylic acid, and 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic acid; polyacrylic acid, polymethacrylic acid, polyamic acid, and carboxylic acid or carboxylic acid anhydride-containing polymers such as polymaleic anhydride. The amount of the compound to be added is, for example, 20% by mass or less, preferably 10% by mass or less, based on the solid content of the coating film-forming composition for removing foreign matter, as needed.

[0098] In order to adjust the dissolution rate in the removal solution, a compound having a carboxyl group or a phenolic hydroxy group protected with a group that is easily decomposed in the presence of an acid, such as a tert-butyl group, a tetrahydropyranyl group, a 1-ethoxyethyl group, or a trimethylsilyl group, can also be added to the coating film-forming composition for removing foreign matter.

[0099] Examples of such compounds include di-tert-butyl malonate, tert-butyl acetate, tert-butyl propionate, tert-butyl acetoacetate, tert-amyl acetate, benzoic acid-tert-butyl ester, and tert-butyl pivalate.

[0100] These compounds readily generate carboxyl groups or phenolic hydroxy groups in the presence of acid, thereby providing compounds with increased solubility in alkaline removal solutions. Therefore, these compounds are preferably added to the coating film-forming composition for removing foreign matter together with a photoacid generator. That is, in a foreign matter removal coating film formed from the coating film-forming composition for removing foreign matter, which contains the above-mentioned compound having a carboxyl group or a phenolic hydroxy group protected by a group that is readily decomposed in the presence of acid and a photoacid generator, the acid generated from the photoacid generator upon exposure regenerates the carboxyl group or phenolic hydroxy group of the compound having the carboxyl group or phenolic hydroxy group protected by a group that is readily decomposed in the presence of acid in the exposed portion of the coating film, thereby increasing the solubility of the foreign matter removal coating film in the alkaline removal solution in the exposed portion.

[0101] When the compound having a carboxyl group or a phenolic hydroxy group protected by a group that is easily decomposed in the presence of an acid is used, the content thereof is, for example, 50 to 1 part by mass, or 30 to 5 parts by mass, or for example, 20 to 10 parts by mass, relative to 100 parts by mass of the polymer. When a photoacid generator is used together with a compound having a carboxyl group or a phenolic hydroxy group protected by a group that is easily decomposed in the presence of an acid, the content thereof is, for example, 0.1 to 30 parts by mass, or 0.5 to 20 parts by mass, or for example, 1 to 10 parts by mass, relative to 100 parts by mass of the compound having a carboxyl group or a phenolic hydroxy group protected by a group that is easily decomposed in the presence of an acid.

[0102] The coating film-forming composition for removing foreign matter can contain a surfactant. Examples of the surfactant include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, and polyoxyethylene oleyl ether, polyoxyethylene alkylaryl ethers such as polyoxyethylene octylphenol ether and polyoxyethylene nonylphenol ether, polyoxyethylene-polyoxypropylene block copolymers, sorbitan fatty acid esters such as sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, and sorbitan tristearate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, and the like. nonionic surfactants such as polyoxyethylene sorbitan fatty acid esters, such as polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, and polyoxyethylene sorbitan tristearate; fluorosurfactants such as EFTOP EF301, EF303, and EF352 (trade names, manufactured by Tochem Products Co., Ltd.), Megafac F171 and F173 (trade names, manufactured by DIC Corporation), Fluorad FC430 and FC431 (trade names, manufactured by Sumitomo 3M Limited), Asahiguard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, and SC106 (trade names, manufactured by AGC Inc.); and organosiloxane polymer KP341 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.). The amount of these surfactants to be added is usually 0.2% by mass or less, and preferably 0.1% by mass or less, of the total components of the coating film-forming composition for removing foreign matter. These surfactants may be added alone or in combination of two or more.

[0103] The coating film-forming composition for removing foreign matter may contain silica particles. Examples of the silica particles include silicone powder having a predetermined average particle size and silica sol containing silica having a predetermined average particle size.

[0104] Specific examples of silicone powders include silicone powders KMP series KMP-600, KMP-601, KMP-602, KMP-605, and X-52-7030 manufactured by Shin-Etsu Chemical Co., Ltd., but are not limited to these.

[0105] Specific examples of colloidal silica (silica sol) include MA-ST-S (methanol-dispersed silica sol), MT-ST (methanol-dispersed silica sol), MA-ST-UP (methanol-dispersed silica sol), trade names MA-ST-M (methanol-dispersed silica sol), MA-ST-L (methanol-dispersed silica sol), IPA-ST-S (isopropanol-dispersed silica sol), IPA-ST (isopropanol-dispersed silica sol), IPA-ST-UP (isopropanol-dispersed silica sol), IPA-ST-L (isopropanol-dispersed silica sol), IPA-ST-ZL (isopropanol-dispersed silica sol), NPC-ST-30 (n-propyl cellosolve-dispersed silica sol), and PGM-ST, all manufactured by Nissan Chemical Industries, Ltd. Examples of silica sols include, but are not limited to, silica sols dispersed in 1-methoxy-2-propanol, DMAC-ST (silica sol dispersed in dimethylacetamide), XBA-ST (silica sol dispersed in a xylene / n-butanol mixed solvent), trade name EAC-ST (silica sol dispersed in ethyl acetate), PMA-ST (silica sol dispersed in propylene glycol monomethyl ether acetate), MEK-ST (silica sol dispersed in methyl ethyl ketone), MEK-ST-UP (silica sol dispersed in methyl ethyl ketone), MEK-ST-L (silica sol dispersed in methyl ethyl ketone), and MIBK-ST (silica sol dispersed in methyl isobutyl ketone).

[0106] (Coating Film for Removing Foreign Matter) The coating film for removing foreign matter of the present invention is formed from the coating film-forming composition for removing foreign matter of the present invention.

[0107] The coating film for removing foreign matter of the present invention can be formed, for example, as follows. The coating film-forming composition for removing foreign matter of the present invention is applied to a semiconductor substrate by an appropriate application method such as a spinner, coater, or immersion, and then baked to form a coating film for removing foreign matter. Baking conditions are appropriately selected from a baking temperature of 80°C to 300°C and a baking time of 0.3 to 60 minutes.

[0108] The thickness of the coating film for removing foreign matter is usually 5 nm to 1 μm, preferably 10 nm to 500 nm, and most preferably 15 nm to 300 nm.

[0109] The dissolution rate of the formed coating film for removing foreign matter in the removal solution, in terms of the rate of film thickness reduction, is, for example, 0.1 to 50 nm per second, preferably 0.2 to 40 nm per second, and more preferably 0.3 to 20 nm per second. If the dissolution rate is lower than this range, the time required to remove the coating film for removing foreign matter will be longer, resulting in a decrease in productivity.

[0110] The dissolution rate of the coating film for removing foreign matter formed from the coating film-forming composition for removing foreign matter of the present invention in a removal solution can be controlled by changing the baking conditions during formation. For a given baking time, the higher the baking temperature, the lower the dissolution rate of the coating film for removing foreign matter in a removal solution that can be formed.

[0111] The foreign matter removal coating film may be exposed to light after the film is formed. The exposure may be performed by exposing the entire wafer or through a mask having a predetermined pattern. For the exposure, a KrF excimer laser (wavelength 248 nm), an ArF excimer laser (wavelength 193 nm), an F2 excimer laser (wavelength 157 nm), or the like may be used. After the exposure, post-exposure baking (PEB) may also be performed as necessary.

[0112] (Semiconductor Substrate) The semiconductor substrate of the present invention has thereon the coating film for removing foreign matter of the present invention.

[0113] The main material constituting the entire semiconductor substrate is not particularly limited as long as it is suitable for this type of application, and examples thereof include silicon, silicon carbide, and compound semiconductors. The shape of the semiconductor substrate is not particularly limited, and may be, for example, a disk. Note that the surface of a disk-shaped semiconductor substrate does not need to be perfectly circular; for example, the outer periphery of the semiconductor substrate may have a straight portion called an orientation flat or a notch. The thickness of the disk-shaped semiconductor substrate may be determined appropriately depending on the intended use of the semiconductor substrate, and is not particularly limited, and is, for example, 500 to 1,000 μm. The diameter of the disk-shaped semiconductor substrate may be determined appropriately depending on the intended use of the semiconductor substrate, and is not particularly limited, and is, for example, 100 to 1,000 mm.

[0114] The semiconductor substrate may have bumps. Bumps are protruding terminals. When a semiconductor substrate has bumps, the bumps are located on the supporting substrate side. In a semiconductor substrate, the bumps are typically formed on the surface on which a circuit is formed. The circuit may be single-layered or multi-layered. The shape of the circuit is not particularly limited. In a semiconductor substrate, the surface opposite to the surface having the bumps (the back surface) is the surface used for processing. The material, size, shape, structure, and density of the bumps on the semiconductor substrate are not particularly limited. Examples of bumps include ball bumps, printed bumps, stud bumps, and plated bumps. The height, radius, and pitch of the bumps are typically determined appropriately based on the following conditions: a bump height of approximately 1 to 200 μm, a bump radius of 1 to 200 μm, and a bump pitch of 1 to 500 μm. Examples of bump materials include low-melting-point solder, high-melting-point solder, tin, indium, gold, silver, and copper. The bump may be composed of only a single component or multiple components. More specifically, examples include alloy platings mainly containing Sn, such as SnAg bumps, SnBi bumps, Sn bumps, and AuSn bumps. The bump may also have a laminate structure including a metal layer composed of at least one of these components.

[0115] An example of a semiconductor substrate is a silicon wafer with a diameter of about 300 mm and a thickness of about 770 μm.

[0116] (Method for manufacturing a processed semiconductor substrate) The method for manufacturing a processed semiconductor substrate of the present invention includes a first step, a second step, a third step, and a fourth step. The first step is a step of manufacturing a laminate by bonding the semiconductor substrate of the present invention (a semiconductor substrate having a foreign matter removal coating film of the present invention) and a supporting substrate via the foreign matter removal coating film. The second step is a step of processing the laminate. The third step is a step of peeling the supporting substrate from the laminate. The fourth step is a step of washing the semiconductor substrate or supporting material with a removing liquid to remove the foreign matter removal coating film. In the first embodiment, the heat-resistant foreign matter removal coating film of the present invention is used as the foreign matter removal coating film.

[0117] <First Step> The first step is a step of manufacturing a laminate by bonding the semiconductor substrate of the present invention (semiconductor substrate having the coating film for removing foreign matter of the present invention) and a supporting substrate via the coating film for removing foreign matter.

[0118] The supporting substrate is not particularly limited as long as it is a member that can support a semiconductor substrate when the laminate (e.g., semiconductor substrate) is processed, and examples thereof include a flexible supporting substrate and a glass supporting substrate.

[0119] The shape of the support substrate is not particularly limited, but may be, for example, a disk shape. The thickness of the disk-shaped support substrate may be determined appropriately depending on the size of the semiconductor substrate, etc., but is not particularly limited, and is, for example, 500 to 1,000 μm. The diameter of the disk-shaped support substrate may be determined appropriately depending on the size of the semiconductor substrate, etc., but is not particularly limited, and is, for example, 100 to 1,000 mm.

[0120] An example of the support substrate is a glass wafer having a diameter of about 300 mm and a thickness of about 700 μm.

[0121] The first step is preferably a step of manufacturing a laminate by bonding a semiconductor substrate and a supporting base material together via a coating film for removing foreign matter and an adhesive layer.

[0122] The adhesive layer is not particularly limited as long as it allows the supporting substrate to be peeled off from the laminate in step 3. The adhesive layer can be formed using a known adhesive and method. Examples of adhesives that can be used include coating-type wafer temporary adhesives described in International Publication No. 2015 / 190438, Thin Materials' temporary bonding material (Nissan Chemical Industries, Ltd.), semiconductor wafer temporary bonding materials manufactured by Toray Industries, Inc., WaferBOND (registered trademark) CR-200, HT-10.10 (manufactured by Brewer Science), and tape-like adhesives (for example, backgrinding tape (for example, 3MTM temporary fixing adhesive tape ATT-4025 (manufactured by 3M Japan Ltd.), E series, P series, S series (manufactured by Lintec Corporation, trade names), ICROS Tape (manufactured by Mitsui Chemicals Tocello Co., Ltd.)), dicing tape (for example, solvent-resistant dicing tape (manufactured by Nitto Denko Corporation, trade name), temperature-sensitive adhesive sheet Intelimer (registered trademark) tape (manufactured by Nitta Corporation), Intelimer (registered trademark) tape (manufactured by Anchor Techno Co., Ltd.), etc.). Specific wafer handling systems (for example, Zero It may also be a wafer adhesive applied to Newton (registered trademark) (manufactured by Tokyo Ohka Kogyo Co., Ltd.). In addition, as the adhesive layer, what is called a pressure-sensitive adhesive layer, pressure-sensitive adhesive tape, or temporary fixing material may be used. Examples of such materials include the pressure-sensitive adhesive layer described in WO 2021 / 225163, the adhesive layer described in WO 2022 / 065376, and the photocurable adhesive layer described in WO 2022 / 065388.

[0123] For example, backgrinding tape is composed of a base film, an adhesive layer, and a release film. While soft thermoplastic films such as ethylene-vinyl acetate copolymer (EVA) have traditionally been used as base films, attempts have also been made to use rigid stretched films such as polyethylene terephthalate (PET) to improve wafer support. Further improvements have since been made, and laminate designs of two types of films with different elastic moduli, such as a laminate design of PET and an ethylene-based copolymer, or a laminate design of polypropylene (PP) and an ethylene-based copolymer, have been reported.

[0124] Acrylic adhesives are commonly used. Acrylic adhesives are known to be designed by crosslinking an acrylic copolymer, primarily made from a monomer with a low glass transition temperature, such as butyl acrylate, with a curing agent. Backgrinding tape is applied to the circuit surface of a wafer, raising concerns about contamination from the adhesive after tape removal. Some designs have been reported that use emulsion-based adhesives, with the expectation that any remaining adhesive can be removed by washing with water, but complete removal is difficult. Therefore, by forming an adhesive layer after forming the coating film for foreign matter removal of the present application on the circuit surface, foreign matter (residue from the adhesive layer) can be completely removed by washing with a remover during the subsequent peeling process, without causing damage to the wiring of the circuit or other components.

[0125] The thickness of the adhesive layer is not particularly limited, but is, for example, 5 μm to 500 μm, preferably 10 μm to 300 μm, more preferably 20 μm to 200 μm, and particularly preferably 30 μm to 150 μm.

[0126] Before carrying out the first step, the adhesive layer may be formed on a coating film for removing foreign matter, on a supporting substrate, or on a semiconductor substrate.

[0127] When no adhesive layer is used, the support substrate preferably has a pressure-sensitive adhesive layer. The support substrate has, for example, a flexible support and a pressure-sensitive adhesive layer. Examples of the flexible support include a polyimide film. The pressure-sensitive adhesive layer is not particularly limited, and examples thereof include a layer formed from the above-mentioned pressure-sensitive adhesive.

[0128] The lamination is carried out, for example, under heating and pressure. The heating temperature is not particularly limited as long as it is at least room temperature (25°C), but is usually at least 50°C. From the viewpoint of avoiding excessive heating, it is usually at most 220°C, and in one embodiment, at most 170°C. The load is not particularly limited as long as it allows the substrates and layers to be bonded together and does not damage the substrates or layers, but is, for example, 0.5 to 50 kN. The pressure during lamination is, for example, 0.1 to 20 N / mm ２ The pressure is measured by the unit area (mm ２ The degree of reduced pressure is not particularly limited as long as it allows the substrate and layer to be bonded together and does not damage the substrate or layer, but is, for example, 10 to 10,000 Pa.

[0129] When an adhesive layer is used, the layer structure of the laminate produced in the first step may be semiconductor substrate / foreign-matter removal coating film / adhesive layer / supporting substrate, with the aim of removing foreign matter, which is the peeling residue of the adhesive layer, together with the foreign-matter removal coating film in the fourth step, and ensuring that no foreign matter is present on the semiconductor substrate. Furthermore, when an adhesive layer is used, the layer structure of the laminate produced in the first step may be semiconductor substrate / adhesive layer / foreign-matter removal coating film / supporting substrate, with the aim of removing foreign matter, which is the peeling residue of the adhesive layer, together with the foreign-matter removal coating film in the fourth step, and ensuring that no foreign matter is present on the supporting substrate. In this case, the supporting substrate can be easily reused. Furthermore, the layer structure of the laminate produced in the first step may be semiconductor substrate / foreign-matter removal coating film / adhesive layer / foreign-matter removal coating film / supporting substrate, with the aim of ensuring that no foreign matter is present on the semiconductor substrate and supporting substrate.

[0130] The laminate produced in the first step may have a laser peeling layer between the semiconductor substrate and the support substrate. If the laminate has a laser peeling layer, in the third step, the support substrate may be peeled off from the laminate, for example, by irradiating the laser peeling layer with a laser. The laser is irradiated, for example, onto the laser peeling layer from the side of the support substrate that is transparent to laser light. If the laminate has a laser peeling layer, in the fourth step, foreign matter, which is peel residue of the laser peeling layer and adhesive layer, is removed together with the foreign matter removal coating film, so that the semiconductor substrate is free of foreign matter. The layer structure of the laminate produced in the first step may be, for example, semiconductor substrate / foreign matter removal coating film / laser peeling layer / adhesive layer / support substrate. If the laminate has a laser peeling layer, in the fourth step, foreign matter, which is peel residue of the laser peeling layer and adhesive layer, is removed together with the foreign matter removal coating film, so that the support substrate is free of foreign matter. The layer structure of the laminate produced in the first step may be, for example, semiconductor substrate / adhesive layer / laser peeling layer / foreign matter removal coating film / support substrate. In this case, the support substrate can be easily reused. Furthermore, if a peeling residue of the laser peeling layer remains on the adhesive layer after peeling the support substrate from the laminate by irradiating the laser peeling layer with a laser, foreign matter originating from the laser peeling layer may re-adhere to the semiconductor substrate or the support substrate, which may increase the time required to clean the adhesive layer. In order to prevent this, the layer structure of the laminate produced in the first step for the purpose of removing the residue of the laser peeling layer on the adhesive layer may be semiconductor substrate / adhesive layer / coating film for removing foreign matter / laser peeling layer / support substrate, or semiconductor substrate / laser peeling layer / coating film for removing foreign matter / adhesive layer / support substrate.

[0131] <Second Step> The second step is a step of processing the laminate. The processing in the second step is not particularly limited, but examples thereof include polishing of the semiconductor substrate, forming a through electrode in the semiconductor substrate, and connecting the semiconductor substrate and a second semiconductor substrate. The processing in the second step may include one of these processes or two or more of them.

[0132] <<Polishing Treatment>> The polishing treatment of a semiconductor substrate is not particularly limited as long as it is a treatment for polishing the surface of the semiconductor substrate opposite to the surface on which the foreign matter removal coating film is formed and thinning the semiconductor substrate, and examples thereof include physical polishing using an abrasive or a grindstone. The polishing treatment can be performed using a general polishing device used for polishing semiconductor substrates (e.g., silicon wafers). The polishing treatment reduces the thickness of the semiconductor substrate, resulting in a semiconductor substrate that has been thinned to a desired thickness. The thickness of the thinned semiconductor substrate is not particularly limited, and may be, for example, 30 to 300 μm or 30 to 100 μm.

[0133] <<Through Electrode Formation Process>> For example, a through electrode may be formed in a polished semiconductor substrate to provide electrical continuity between thinned semiconductor substrates when multiple thinned semiconductor substrates are stacked. Therefore, a through electrode formation process in which a through electrode is formed in the polished semiconductor substrate may be performed after the polishing process and before the peeling process. Methods for forming through electrodes in a semiconductor substrate are not particularly limited, but examples include forming through holes and filling the formed through holes with a conductive material. The through holes are formed, for example, by photolithography. The conductive material is filled into the through holes by plating, for example. Note that the through electrode formation process may be performed in the second step without performing the polishing process.

[0134] <<Connection Processing>> The connection processing is, for example, processing for connecting a semiconductor substrate and a second semiconductor substrate. The second semiconductor substrate is not particularly limited, and examples thereof include those listed in the above description of the semiconductor substrate. The connection processing is, for example, performed under heating. Furthermore, the connection processing is, for example, performed under pressure. The heating temperature is not particularly limited, and examples thereof include 100°C to 350°C.

[0135] In the connection process, for example, the wiring on the semiconductor substrate and the wiring on the second semiconductor substrate are electrically connected. Such connection is performed, for example, by connecting the ends of the wiring. The material, shape, and structure of the wiring on the semiconductor substrate are not particularly limited. The material, shape, and structure of the wiring on the second semiconductor substrate are not particularly limited.

[0136] <Step 3> Step 3 is a step of peeling the support substrate from the laminate. Step 3 can be said to be a step in which the semiconductor substrate and the support substrate are separated. Peeling methods include, but are not limited to, solvent peeling, peeling by light irradiation (laser light, non-laser light), mechanical peeling using equipment with sharp parts (so-called debonders), and manual peeling between the semiconductor substrate and the support substrate. In particular, when the laminate includes an adhesive layer, and the adhesive layer is formed using an organic resin that absorbs light and undergoes the necessary alteration to improve peelability, the adhesive layer can be peeled, for example, by irradiating it with a laser from the support substrate side. Laser light irradiation is performed using, for example, ultraviolet light with a wavelength of 190 nm to 400 nm or 190 nm to 600 nm (e.g., 308 nm, 355 nm, 532 nm). Peeling is performed using a pulse laser with a processing energy density of 50 to 500 mJ / cm. ２ When the laminate contains an adhesive layer, peeling usually occurs within the adhesive layer or at the interface between the adhesive layer and an adjacent substrate or layer (e.g., a coating film for removing foreign matter). Peeling occurring within the adhesive layer means that the adhesive layer is cleaved.

[0137] <Fourth Step> The fourth step is a step of cleaning the semiconductor substrate or the support substrate with a remover to remove the foreign matter removal coating film. For example, the foreign matter removal coating film remains on the semiconductor substrate that has been peeled off from the support substrate. Therefore, the foreign matter removal coating film is removed with a remover. In the fourth step, for example, the foreign matter is removed together with the foreign matter removal coating film. In the fourth step, for example, the foreign matter, which is a peeled residue of the adhesive layer, is removed together with the foreign matter removal coating film.

[0138] Examples of the removal liquid include the removal liquids mentioned in the description of the coating film-forming composition for removing foreign matter of the present invention. The cleaning method is not particularly limited, but examples include a method of immersing the semiconductor substrate on which the coating film for removing foreign matter remains in the removal liquid, and a method of spraying the removal liquid onto the semiconductor substrate on which the coating film for removing foreign matter remains. The cleaning conditions are not particularly limited, but for example, the temperature of the cleaning liquid is 5°C to 50°C. The cleaning time is appropriately selected from 2 to 500 seconds, or 3 to 400 seconds.

[0139] For example, it is preferable that the foreign matter removal coating film can be easily peeled off at room temperature (for example, 25° C.) using a commonly used 2.38% by mass aqueous solution of tetramethylammonium hydroxide.

[0140] An example of a method for manufacturing a processed semiconductor substrate is described below with reference to the drawings. First, a semiconductor substrate 11 is prepared ( FIG. 1A ). Next, a foreign matter removal coating film 12 is formed on the semiconductor substrate 11 ( FIG. 1B ). Next, the semiconductor substrate 11 with the foreign matter removal coating film 12 shown in FIG. 1B is bonded to a support substrate 14 having a flexible support 14A and an adhesive layer 14B, with the foreign matter removal coating film 12 and the adhesive layer 14B facing each other ( FIG. 1C ). Next, the surface of the semiconductor substrate 11 opposite the surface with the foreign matter removal coating film 12 is polished to thin the semiconductor substrate 11 ( FIG. 1D ). Next, the support substrate 14 is separated from the semiconductor substrate 11 ( FIGS. 1E and 1F ). After separation, a peeled residue 14C of the adhesive layer 14B remains on the foreign matter removal coating film 12 ( FIG. 1F ). Therefore, the foreign matter removal coating film 12 is removed using a remover ( FIG. 1G ). By doing so, it is possible to prevent the peeling residue 14C, which is a foreign substance, from remaining on the semiconductor substrate 11.

[0141] Another example of a method for manufacturing a processed semiconductor substrate is described below with reference to the drawings. First, a semiconductor substrate 1 having wiring 1A is prepared ( FIG. 2A ). Next, a foreign matter removal coating film 2 is formed on the semiconductor substrate 1 ( FIG. 2B ). Separately, a glass substrate 4 having an adhesive layer 3 formed on its surface is prepared ( FIG. 2C ). The semiconductor substrate 1 having the foreign matter removal coating film 2 shown in FIG. 2B and the glass substrate 4 having the adhesive layer 3 shown in FIG. 2C are then bonded together, with the foreign matter removal coating film 2 and the adhesive layer 3 facing each other ( FIGS. 2D and 2E ). Next, the surface of the semiconductor substrate 1 opposite the surface with the foreign matter removal coating film 2 is polished to thin the semiconductor substrate 1 ( FIG. 2F ). Finally, the wiring 1A is exposed. Next, the laminate shown in FIG. 2F and a second semiconductor substrate 5 having wiring 5A are bonded together, with the surface of the semiconductor substrate 1 opposite the surface of the foreign matter removal coating film 2 facing the surface of the second semiconductor substrate 5 on which the wiring 5A is exposed (FIGS. 2G and 2H). Next, the adhesive layer 3 and glass substrate 4 are separated from the semiconductor substrate 1 (FIG. 2I). Separation can be easily achieved, for example, by irradiating the adhesive layer 3 with a laser to reduce the adhesive strength of the adhesive layer 3. After separation, peeling residue 3A of the adhesive layer 3 remains on the foreign matter removal coating film 2 (FIGS. 2I and 2J). Therefore, the foreign matter removal coating film 2 is removed with a remover (FIG. 2K). This prevents the peeling residue 3A from remaining on the semiconductor substrate 1.

[0142] The method for manufacturing a processed semiconductor substrate of the present invention can be suitably used for hybrid bonding, which connects semiconductor substrates together.

[0143] <Other embodiments> One embodiment of the present invention may be a method for removing foreign matter already present on a semiconductor manufacturing substrate.For example, as described in International Publication No. 2017 / 056746 and International Publication No. 2020 / 008965, in the process of forming a substrate processing film on the surface of a semiconductor substrate and removing foreign matter from the substrate surface, a substrate processing film-forming composition and a substrate processing method are disclosed that can efficiently remove fine particles from the substrate surface and easily remove the formed substrate processing film from the substrate surface.The coating film-forming composition for removing foreign matter of the present invention can also be used in the same methods and applications as above.

[0144] The above example will be specifically described below. In this application example, the coating film-forming composition for removing foreign matter of the present invention is used as a composition for forming a coating film on a semiconductor substrate. First, a coating film-forming step is performed. That is, the coating film-forming composition for removing foreign matter is applied to a semiconductor substrate to form a coating film. The semiconductor substrate may be in an unprocessed state or in a state where various films are formed, i.e., a solid substrate (flat), or may be processed to have a shape such as wiring for semiconductor device manufacturing. Examples of coating methods include spin coating, casting coating, and roll coating. Next, the coating film is heated (baked) and / or reduced pressure to efficiently remove part or all of the solvent contained in the coating film, thereby promoting solidification and / or hardening of the solid content contained in the coating film. Here, "solidification" refers to solidification, and "hardening" refers to the process in which molecules bond to each other and increase the molecular weight (e.g., crosslinking, polymerization, etc.). In this manner, a coating film is formed. During this process, for example, particles adhering to the circuitry of the semiconductor substrate are captured by the coating film and efficiently detached from the circuitry. Next, a coating film removal step is performed. That is, a remover that dissolves the coating film is supplied onto the coating film to remove the entire coating film from the semiconductor substrate. As a result, the particles are removed from the semiconductor substrate together with the coating film.

[0145] Next, the present invention will be explained in detail with reference to synthesis examples and examples, but the present invention is not limited to these.

[0146] <Measurement of Molecular Weight> The weight average molecular weights of the polymers shown in Synthesis Examples 1 to 8 below were measured by gel permeation chromatography (hereinafter abbreviated as GPC). A GPC device manufactured by Tosoh Corporation was used for the measurement, and the measurement conditions were as follows: GPC column: Shodex GF-710, Shodex GF-510HQ, Shodex GF-310HQ (registered trademark) (Showa Denko K.K.) Column temperature: 40°C Flow rate: 0.6 ml / min Eluent: N,N-dimethylformamide (DMF) Standard sample: polystyrene (Tosoh Corporation)

[0147] Synthesis Example 1 A solution of 4.00 g of 2-hydroxypropyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.), 1.57 g of 2-oxotetrahydrofuran-3-yl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.11 g of dimethyl 2,2'-azobis(isobutyrate) (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), and 18.19 g of propylene glycol monomethyl ether was added to a dropping funnel, and the mixture was added dropwise at 80°C under a nitrogen atmosphere to a reaction flask containing 4.55 g of propylene glycol monomethyl ether, followed by heating and stirring for 16 hours. Thereafter, the solution of the reaction product was added dropwise to a heptane solution, and the resulting precipitate was separated by filtration and dried at 40°C under vacuum. The resulting reaction product corresponded to formula (X-1), and the weight average molecular weight Mw measured in terms of polystyrene by GPC was 57,400. The numerical values ​​in formula (X-1) represent molar proportions (%).

[0148] Synthesis Example 2 A solution of 3.50 g of 2-hydroxyethyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.), 1.53 g of 2-oxotetrahydrofuran-3-yl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.10 g of dimethyl 2,2'-azobis(isobutyrate) (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), and 16.40 g of propylene glycol monomethyl ether was added to a dropping funnel, and the mixture was added dropwise at 80°C under a nitrogen atmosphere to a reaction flask containing 4.10 g of propylene glycol monomethyl ether, followed by heating and stirring for 14 hours. Thereafter, the solution of the reaction product was added dropwise to a heptane solution, and the resulting precipitate was separated by filtration and dried at 40°C under vacuum. The resulting reaction product corresponded to formula (X-2), and the weight average molecular weight Mw measured in terms of polystyrene by GPC was 69,800. The numerical values ​​in formula (X-2) represent molar proportions (%).

[0149] Synthesis Example 3 A solution of 3.50 g of 1-butoxyethyl methacrylate, 1.07 g of 2-oxotetrahydrofuran-3-yl methacrylate (Tokyo Chemical Industry Co., Ltd.), 0.09 g of dimethyl 2,2'-azobis(isobutyrate) (Fujifilm Wako Pure Chemical Industries, Ltd.), and 14.90 g of propylene glycol monomethyl ether was added to a dropping funnel, and the mixture was added dropwise at 80°C under a nitrogen atmosphere to a reaction flask containing 3.73 g of propylene glycol monomethyl ether, followed by heating and stirring for 17 hours. Thereafter, the solution of the reaction product was added dropwise to a heptane solution, and the resulting precipitate was separated by filtration and dried at 40°C under vacuum. The resulting reaction product corresponded to formula (X-3), and the weight average molecular weight Mw measured in terms of polystyrene by GPC was 7,400. The numerical values ​​in formula (X-3) represent molar proportions (%).

[0150] Synthesis Example 4 A solution of 2.80 g of methacrylic acid, 1.84 g of 2-oxotetrahydrofuran-3-yl methacrylate (Tokyo Chemical Industry Co., Ltd.), 0.09 g of dimethyl 2,2'-azobis(isobutyrate) (Fujifilm Wako Pure Chemical Industries, Ltd.), and 15.16 g of propylene glycol monomethyl ether was added to a dropping funnel, and the mixture was added dropwise at 100°C under a nitrogen atmosphere to a reaction flask containing 3.79 g of propylene glycol monomethyl ether, followed by heating and stirring for 16 hours. Thereafter, the solution of the reaction product was added dropwise to a heptane solution, and the resulting precipitate was separated by filtration and dried in vacuo at 40°C. The resulting reaction product corresponded to formula (X-4). The numerical values ​​in formula (X-4) represent molar proportions (%).

[0151] Synthesis Example 5 A solution of 3.80 g of 4-hydroxyphenyl methacrylate (manufactured by Resonac Corporation), 1.21 g of 2-oxotetrahydrofuran-3-yl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.10 g of dimethyl 2,2'-azobis(isobutyrate) (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), and 16.35 g of methyl ethyl ketone was added to a dropping funnel, and the mixture was added dropwise at 80°C under a nitrogen atmosphere to a reaction flask containing 4.09 g of methyl ethyl ketone, followed by heating and stirring for 16 hours. Thereafter, the solution of the reaction product was added dropwise to a hexane solution, and the resulting precipitate was separated by filtration and dried at 40°C under vacuum. The resulting reaction product corresponded to formula (X-5), and had a weight average molecular weight Mw of 36,000 as measured by GPC in terms of polystyrene. The numerical values ​​in formula (X-5) represent molar proportions (%).

[0152] Synthesis Example 6 A solution of 3.50 g of 4-vinylbenzoic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), 1.34 g of 2-oxotetrahydrofuran-3-yl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.10 g of dimethyl 2,2'-azobis(isobutyrate) (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), and 15.80 g of propylene glycol monomethyl ether was added to a dropping funnel, and the mixture was added dropwise at 100°C under a nitrogen atmosphere to a reaction flask containing 3.95 g of propylene glycol monomethyl ether, followed by heating and stirring for 16 hours. Thereafter, the solution of the reaction product was added dropwise to a heptane solution, and the resulting precipitate was separated by filtration and dried in vacuo at 40°C. The resulting reaction product corresponded to formula (X-6). The numerical values ​​in formula (X-6) represent molar proportions (%).

[0153] Synthesis Example 7 A solution of 1.50 g of 1-butoxyethyl methacrylate, 1.37 g of 2-oxotetrahydrofuran-3-yl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.), 2.10 g of hydroxyethyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.10 g of 2,2'-azobis(isobutyrate)dimethyl (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), and 16.21 g of propylene glycol monomethyl ether was added to a dropping funnel, and the mixture was added dropwise at 100°C under a nitrogen atmosphere to a reaction flask containing 4.05 g of propylene glycol monomethyl ether, followed by heating and stirring for 16 hours. Thereafter, the solution of the reaction product was added dropwise to a methanol solution, and the resulting precipitate was separated by filtration and dried in vacuo at 40°C. The resulting reaction product corresponded to formula (X-7), and had a weight average molecular weight Mw of 24,000 as measured by GPC in terms of polystyrene. The numerical values ​​in formula (X-7) represent molar proportions (%).

[0154] Synthesis Example 8 A solution of 3.30 g of 2-hydroxyethyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.), 1.57 g of (2-oxo-1,3-dioxolan-4-yl)methyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.10 g of dimethyl 2,2'-azobis(isobutyrate) (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), and 15.91 g of propylene glycol monomethyl ether was added to a dropping funnel, and the mixture was added dropwise at 100°C under a nitrogen atmosphere to a reaction flask containing 3.98 g of propylene glycol monomethyl ether, followed by heating and stirring for 16 hours. Thereafter, the solution of the reaction product was added dropwise to a heptane solution, and the resulting precipitate was separated by filtration and dried at 40°C under vacuum. The resulting reaction product corresponded to formula (X-8), and had a weight average molecular weight Mw of 25,000 as measured by GPC in terms of polystyrene. The numerical values ​​in formula (X-8) represent molar proportions (%).

[0155] Example 1 To 1.45 g of the propylene glycol monomethyl ether solution (solid content: 20% by mass) of the reaction product obtained in Synthesis Example 1 was added 18.55 g of propylene glycol monomethyl ether, and the mixture was then filtered using a PTFE syringe filter having a pore size of 0.20 μm to prepare a coating film-forming composition for removing foreign matter.

[0156] Example 2 To 1.45 g of the propylene glycol monomethyl ether solution (solid content: 20% by mass) of the reaction product obtained in Synthesis Example 2 was added 18.55 g of propylene glycol monomethyl ether, and the mixture was filtered using a PTFE syringe filter having a pore size of 0.20 μm to prepare a coating film-forming composition for removing foreign matter.

[0157] Example 3 To 1.45 g of the propylene glycol monomethyl ether solution (solid content: 20% by mass) of the reaction product obtained in Synthesis Example 3 was added 18.55 g of propylene glycol monomethyl ether, and the mixture was then filtered using a PTFE syringe filter having a pore size of 0.20 μm to prepare a coating film-forming composition for removing foreign matter.

[0158] Example 4 To 1.45 g of the propylene glycol monomethyl ether solution (solid content: 20% by mass) of the reaction product obtained in Synthesis Example 4 was added 18.55 g of propylene glycol monomethyl ether, and the mixture was filtered using a PTFE syringe filter having a pore size of 0.20 μm to prepare a coating film-forming composition for removing foreign matter.

[0159] Example 5 To 1.45 g of the propylene glycol monomethyl ether solution (solid content: 20% by mass) of the reaction product obtained in Synthesis Example 5 was added 18.55 g of propylene glycol monomethyl ether, and the mixture was then filtered using a PTFE syringe filter having a pore size of 0.20 μm to prepare a coating film-forming composition for removing foreign matter.

[0160] Example 6 To 1.45 g of the propylene glycol monomethyl ether solution (solid content: 20% by mass) of the reaction product obtained in Synthesis Example 6 was added 18.55 g of propylene glycol monomethyl ether, and the mixture was filtered using a PTFE syringe filter having a pore size of 0.20 μm to prepare a coating film-forming composition for removing foreign matter.

[0161] Example 7 To 1.45 g of the propylene glycol monomethyl ether solution (solid content: 20% by mass) of the reaction product obtained in Synthesis Example 7 was added 18.55 g of propylene glycol monomethyl ether, and the mixture was filtered using a PTFE syringe filter having a pore size of 0.20 μm to prepare a coating film-forming composition for removing foreign matter.

[0162] Example 8 To 1.45 g of the propylene glycol monomethyl ether solution (solid content: 20% by mass) of the reaction product obtained in Synthesis Example 8 was added 18.55 g of propylene glycol monomethyl ether, and the mixture was filtered using a PTFE syringe filter having a pore size of 0.20 μm to prepare a coating film-forming composition for removing foreign matter.

[0163] [Alkali Dissolution Test] Each of the coating film-forming compositions for removing foreign matter prepared in Examples 1 to 8 was applied (spin coated) onto a silicon wafer using a spin coater. The coated silicon wafer was heated on a hot plate at 140°C for 1 minute to form a 40 nm thick coating film. Next, to confirm the alkali solubility of the coating film, the silicon wafer on which the coating film had been formed was immersed in a 2.38% aqueous solution of tetramethylammonium hydroxide (NMD-3, manufactured by Tokyo Ohka Kogyo Co., Ltd.) for 30 seconds. The thickness of the coating film before and after immersion in the solvent was measured using an optical interference film thickness meter (product name: Lambda Ace VM-3210, manufactured by SCREEN Holdings Co., Ltd.). The alkali solubility was evaluated by calculating and evaluating the film thickness reduction rate (%) of the coating film removed by solvent immersion using the following formula: Film Thickness Reduction Rate (%) = ((A - B) ÷ A) × 100 A: Film thickness before solvent immersion B: Film thickness after solvent immersion The results are shown in Table 1. If the absolute value of the film thickness reduction rate is about 99% or more, it can be said that the film has sufficient alkali solubility.

[0164]

[0165] From the above results, it was confirmed that the coating film-forming compositions for removing foreign matter of Examples 1 to 8 were soluble in alkaline solvents.

[0166] REFERENCE SIGNS LIST 1 Semiconductor substrate 1A Wiring 2 Foreign matter removal coating film 3 Adhesive layer 4 Glass substrate 5 Second semiconductor substrate 5A Wiring 11 Semiconductor substrate 12 Foreign matter removal coating film 14 Support base 14A Flexible support 14B Pressure-sensitive adhesive layer 14C Peeling residue

Claims

1. A coating film-forming composition for removing foreign matter, which comprises a polymer and a solvent and can form a coating film that can be removed by a removal solution, wherein the polymer is —O—C(═O)—(O) ｍ The composition is a polymer comprising a structural unit (A) having a ring structure containing a - group (m represents 0 or 1).

2. The composition according to claim 1, wherein the structural unit (A) is a structural unit represented by the following formula (A-1): [In formula (A-1), R １ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms; X １ represents an ester group or an amide group. １ represents a single bond or an alkylene group having 1 to 6 carbon atoms. Q represents a ring structure (r) having 3 to 10 carbon atoms and containing a lactone ring or a carbonate ring, which may be substituted. The ring structure (r) may be polycyclic.

3. The composition according to claim 1, wherein the polymer further comprises a structural unit (B) having a hydroxy group, a carboxy group, an imide group, or a compound having a protecting group introduced into a hydroxy group or a carboxy group.

4. The composition of claim 1, wherein the removal solution is an alkaline removal solution.

5. The composition of claim 1, further comprising at least one of a crosslinking agent and an additive.

6. A coating film for removing foreign matter formed from the composition according to any one of claims 1 to 5.

7. A semiconductor substrate having the coating film for removing foreign matter according to claim 6.

8. A method for manufacturing a processed semiconductor substrate, comprising: a first step of manufacturing a laminate by bonding the semiconductor substrate according to claim 7 and a supporting substrate with the foreign matter removal coating film interposed therebetween; a second step of processing the laminate; a third step of peeling the supporting substrate from the laminate; and a fourth step of washing the semiconductor substrate or the supporting substrate with a removing liquid to remove the foreign matter removal coating film.

9. The method for producing a processed semiconductor substrate according to claim 8, wherein the fourth step removes foreign matter together with the foreign matter removal coating film.

10. A method for producing a processed semiconductor substrate as described in claim 8, wherein the first step is a step of producing a laminate by bonding the semiconductor substrate and the support base material together via the foreign matter removal coating film and adhesive layer.

11. The method for manufacturing a semiconductor substrate according to claim 10, wherein in the fourth step, foreign matter, which is a peeled residue of the adhesive layer, is removed together with the foreign matter removal coating film.

12. The method of claim 8, wherein said processing includes connecting said semiconductor substrate with a second semiconductor substrate.

Images