Composition for forming protective film

Abstract

A composition for forming a protective film resistant to a wet etching solution for semiconductors, comprising: component (A): a film-forming component; component (B): at least one of a triazole compound (B-1), a tetrazole compound (B-2), a compound (B-3) having two or more phenolic hydroxyl groups, and a compound (B-4) having two or more non-phenolic hydroxyl groups; and component (C): a solvent.

Description

Technical Field

[0001] The present invention relates to a composition for forming a protective film having excellent resistance to a wet etching solution for semiconductors, particularly in a lithography process in semiconductor manufacturing. Further, the present invention relates to a protective film formed from the composition, a method for manufacturing a substrate with a resist pattern to which the protective film is applied, and a method for manufacturing a semiconductor device. Background Art

[0002] In semiconductor manufacturing, a lithography process in which a resist underlayer film is provided between a substrate and a resist film formed thereon to form a resist pattern in a desired shape is well known. After the resist pattern is formed, the substrate is processed. As this process, dry etching is mainly used, but wet etching is sometimes used depending on the type of substrate. In Patent Document 1, a resist underlayer film material having resistance to alkaline hydrogen peroxide water is disclosed.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2018-173520 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] When a protective film of a semiconductor substrate is formed using a composition for forming a protective film and the protective film is used as an etching mask for processing a base substrate by wet etching, the protective film is required to have a good masking function for a wet etching solution for semiconductors (that is, the masked portion can protect the substrate).

[0008] Furthermore, it is expected that the protective film for the above purpose has a function as a resist underlayer film for solving problems (such as poor shape) during resist pattern formation.

[0009] The present invention has been made in view of the above circumstances, and an object thereof is to provide a composition for forming a protective film that can form a protective film having excellent resistance to a wet etching solution for semiconductors and can also be effectively used as a composition for forming a resist underlayer film.

[0010] Means for Solving the Problems

[0011] The present inventors conducted intensive studies to solve the above problems, and as a result, found that by making a composition for forming a protective film contain a specific component (A) and a specific component (B), the above problems can be solved, and thus the present invention was completed.

[0012] That is, the present invention includes the following aspects.

[0013] [1] A composition for forming a protective film resistant to wet etching liquid for semiconductors, which comprises:

[0014] Component (A): A film-forming component,

[0015] Component (B): At least any one of a triazole compound (B-1), a tetrazole compound (B-2), a compound having two or more phenolic hydroxyl groups (B-3), and a compound having two or more non-phenolic hydroxyl groups (B-4), and

[0016] Component (C): A solvent.

[0017] [2] The composition for forming a protective film according to [1], wherein the component (A) comprises a compound having a theoretical molecular weight of 999 or less.

[0018] [3] The composition for forming a protective film according to [1], wherein the compound having a theoretical molecular weight of 999 or less is a compound having a theoretical molecular weight of 999 or less represented by the following formula (1).

[0019]

[0020] (In formula (1), Z1 represents a p-valent group containing a nitrogen-containing heterocycle.

[0021] p represents an integer of 2 to 4.

[0022] Each U independently represents a monovalent organic group represented by the following formula (2).)

[0023]

[0024] (In formula (2), R1 represents an alkylene group having 1 to 4 carbon atoms.

[0025] T represents a single bond or an (s + 1)-valent hydrocarbon group having 1 to 8 carbon atoms.

[0026] A1 to A3 each independently represent a hydrogen atom, a methyl group, or an ethyl group.

[0027] X represents -COO-, -OCO-, -O-, -S-, or -NR a -, R a represents a hydrogen atom or a methyl group.

[0028] Y represents a single bond or an alkylene group having 1 to 4 carbon atoms which may be substituted.

[0029] R2, R3, and R4 each independently represent a hydrogen atom, or an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 40 carbon atoms which may be substituted.

[0030] R5 represents a hydrogen atom or a hydroxyl group.

[0031] m1, m2, and q each independently represent an integer 0 or 1.

[0032] s represents an integer 1 or 2.

[0033] * represents the bonding moiety with Z1 in formula (1).

[0034] Wherein, when T is a single bond, m1 and q are not both 1.

[0035] [4] The composition for forming a protective film according to [3], wherein Z1 is represented by the following formula (3-1) or formula (3-2).

[0036]

[0037] (In formula (3-1), Q3 represents the following formula (4), formula (5), formula (6), or formula (7).

[0038] * each represents the bonding moiety with U in formula (1).

[0039]

[0040] (In formula (4), formula (5), formula (6), and formula (7),

[0041] R 11 ~R 15 each independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom, an alkenyl group having 2 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom, an alkynyl group having 2 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom, a benzyl group, or a phenyl group, and the phenyl group may be substituted by at least one monovalent functional group selected from an alkyl group having 1 to 6 carbon atoms, a halogen atom, an alkoxy group having 1 to 10 carbon atoms, a nitro group, a cyano group, and an alkylthio group having 1 to 6 carbon atoms.

[0042] * represents a bonding bond. *1 represents a bonding bond with the nitrogen atom in formula (3-1). *2 represents a bonding bond with the carbon atom in formula (3-1). *3 represents the bonding moiety with U in formula (1).

[0043] [5] The composition for forming a protective film according to any one of [1] to [4], wherein the triazole compound (B-1) is at least any one of the compounds represented by the following formula (B-1-1), the compound represented by the following formula (B-1-2), the compound represented by the following formula (B-1-3), and the compound represented by the following formula (B-1-4).

[0044]

[0045] (In formulas (B-1-1) to (B-1-4), R 11 ~R 20 each independently represents a group formed of one or more atoms selected from a hydrogen atom, a carbon atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, a silicon atom, and a halogen atom.

[0046] R 14 and R 15 may together form a ring structure.

[0047] m and n each independently represent an integer from 0 to 4.

[0048] When m is 2 or more, two or more R 18 may be the same or different.

[0049] When n is 2 or more, two or more R 20 may be the same or different.)

[0050] [6] The composition for forming a protective film according to any one of [1] to [5], wherein the tetrazole compound (B-2) is a compound represented by the following formula (B-2-1).

[0051]

[0052] (In formula (B-2-1), R 21 and R 22 each independently represent a group formed of one or more atoms selected from a hydrogen atom, a carbon atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, a silicon atom, and a halogen atom.

[0053] R 21 and R 22 may together form a ring structure.)

[0054] [7] The composition for forming a protective film according to any one of [1] to [6], wherein the compound (B-3) is at least any one of a compound (B-3-1) represented by the following formula (11a), a compound (B-3-2) represented by the following formula (11b), and a compound having a group represented by the following formula (12) and having a molecular weight of 300 or more and less than 800 or a compound having a weight average molecular weight of 300 or more and less than 800 (B-3-3).

[0055]

[0056] (In formulas (11a), (11b), and (12), R 31 represents a single bond, an alkylene group having 1 to 4 carbon atoms, or an alkenylene group having 2 to 4 carbon atoms.

[0057] k represents an integer 0 or 1.

[0058] m represents an integer from 1 to 3.

[0059] n represents an integer from 2 to 4.

[0060] * represents a combination key. )

[0061] [8] The composition for forming a protective film according to any one of [1] to [7], wherein the compound (B-4) having two or more non-phenolic hydroxyl groups is a compound represented by the following formula (B-4-1).

[0062]

[0063] (In the formula (B-4-1), X represents -O- or -NR- (R represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms which may have a hydroxyl group, an aryl group having 6 to 12 carbon atoms which may have a substituent, or an aralkyl group having 7 to 13 carbon atoms which may have a substituent). ).

[0064] n represents an integer from 1 to 3. When n is 2 or 3, X may be the same or different. )

[0065] [9] A protective film resistant to a wet etching solution for semiconductors, which is a fired product of a coating film formed from the composition for forming a protective film according to any one of [1] to [8].

[0066]

[10] A method for manufacturing a substrate with a protective film used in the manufacture of a semiconductor, which includes the following steps:

[0067] A step of coating the composition for forming a protective film according to any one of [1] to [8] on a semiconductor substrate having a height difference and firing to form a protective film.

[0068]

[11] A method for manufacturing a substrate with a resist pattern used in the manufacture of a semiconductor, which includes the following steps:

[0069] A step of coating the composition for forming a protective film according to any one of [1] to [8] on a semiconductor substrate and firing to form a protective film as an underlayer film for a resist, and

[0070] A step of forming a resist film directly or via another layer on the protective film, and then performing exposure and development to form a resist pattern.

[0071]

[12] A method for manufacturing a semiconductor device, which includes the following steps:

[0072] On a semiconductor substrate having an inorganic film formed on its surface, a protective film is formed using the composition for forming a protective film described in any one of [1] to [8]. An antireflective pattern is formed directly on the protective film or via another layer. The surface of the inorganic film is exposed by dry-etching the protective film using the antireflective pattern as a mask. The inorganic film is wet-etched using a semiconductor wet etching solution with the protective film after dry-etching as a mask.

[0073] Effects of the Invention

[0074] According to the present invention, there can be provided a composition which is a composition for forming a protective film capable of forming a protective film having excellent resistance to a semiconductor wet etching solution, and can also be effectively used as a composition for forming an antireflective underlayer film. Detailed Description of the Invention

[0075] (Composition for Forming a Protective Film)

[0076] The composition for forming a protective film of the present invention is a composition for forming a protective film.

[0077] The protective film is preferably a protective film that protects the inorganic film on the semiconductor substrate having an inorganic film formed on its surface from wet etching.

[0078] The composition for forming a protective film contains component (A), component (B), and component (C) a solvent.

[0079] Component (A) is a film-forming component.

[0080] Component (B) is at least any one of a triazole compound (B-1), a tetrazole compound (B-2), a compound (B-3) having two or more phenolic hydroxyl groups, and a compound (B-4) having two or more non-phenolic hydroxyl groups.

[0081] Component (C) is a solvent.

[0082] <Component (A)>

[0083] Component (A) is a film-forming component.

[0084] As the film-forming component, for example, as long as it is a compound that forms a film by coating on a substrate and heating, there is no particular limitation, but a compound having a theoretical molecular weight of 999 or less is preferred.

[0085] More preferably, the film-forming component is a compound represented by the following formula (1) and having a theoretical molecular weight of 999 or less.

[0086]

[0087] (In formula (1), Z1 represents a p-valent group containing a nitrogen-containing heterocycle.

[0088] p represents an integer from 2 to 4.

[0089] Each U independently represents a monovalent organic group represented by the following formula (2).

[0090]

[0091] (In formula (2), R1 represents an alkylene group having 1 to 4 carbon atoms.

[0092] T represents a single bond or an (s + 1)-valent hydrocarbon group having 1 to 8 carbon atoms.

[0093] A1 to A3 each independently represent a hydrogen atom, a methyl group or an ethyl group.

[0094] X represents -COO-, -OCO-, -O-, -S- or -NR a -, R a represents a hydrogen atom or a methyl group.

[0095] Y represents a single bond or an alkylene group having 1 to 4 carbon atoms which may be substituted.

[0096] R2, R3 and R4 each independently represent a hydrogen atom, or an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 40 carbon atoms which may be substituted.

[0097] R5 represents a hydrogen atom or a hydroxyl group.

[0098] m1, m2 and q each independently represent an integer 0 or 1.

[0099] s represents an integer 1 or 2.

[0100] * represents the bonding portion with Z1 in formula (1).

[0101] Wherein, when T is a single bond, m1 and q are not both 1.

[0102] The above-mentioned theoretical molecular weight refers to the molecular weight calculated based on the chemical structure of the compound represented by formula (1).

[0103] From the viewpoint of improving the dry etching rate, the compound represented by formula (1) preferably contains 2 or more, 3 or more, 4 or more nitrogen atoms, and 6 or more, 8 or more, 9 or more, 10 or more, 15 or more oxygen atoms in the molecule. It is preferred that the molecule further contains 2 or more, 3 or more, 4 or more, 5 or more, 6 or more sulfur atoms.

[0104] It is preferred that m2 in formula (2) is 1.

[0105] When s in formula (2) is 2, it is preferred that q is 1.

[0106] X in formula (2) is preferably -S-.

[0107] For example, when s is 1, m1 is 0 or 1, m2 is 1, T is a single bond or an alkylene group having 1 to 8 carbon atoms, and q is 0 or 1. Among them, when T is a single bond, m1 and q are not both 1.

[0108] For example, when s is 2, m1 is 1, m2 is 1, T is a trivalent hydrocarbon group having 1 to 8 carbon atoms, and q is 1.

[0109] In this specification, examples of the alkylene group include methylene, ethylene, 1,3 - propylene, 1 - methylethylene, 1,4 - butylene, 1 - ethylethylene, 1 - methylpropylene, 2 - methylpropylene, 1,5 - pentylene, 1 - methylbutylene, 2 - methylbutylene, 1,1 - dimethylpropylene, 1,2 - dimethylpropylene, 1 - ethylpropylene, 2 - ethylpropylene, 1,6 - hexylene, 1,4 - cyclohexylene, 1,8 - octylene, 2 - ethyloctylene, 1,9 - nonylene, 1,10 - decylene, and the like.

[0110] "May be substituted" in Y in formula (2) means that some or all of the hydrogen atoms in the substituted functional group can be substituted by, for example, a hydroxyl group, a halogen atom, a carboxyl group, a nitro group, a cyano group, a methylenedioxy group, an acetoxy group, a methylthio group, an amino group, or an alkoxy group having 1 to 9 carbon atoms.

[0111] In this specification, examples of the aryl group include phenyl, o - methylphenyl, m - methylphenyl, p - methylphenyl, o - chlorophenyl, m - chlorophenyl, p - chlorophenyl, o - fluorophenyl, p - fluorophenyl, o - methoxyphenyl, p - methoxyphenyl, p - nitrophenyl, p - cyanophenyl, α - naphthyl, β - naphthyl, o - biphenyl, m - biphenyl, p - biphenyl, 1 - anthryl, 2 - anthryl, 9 - anthryl, 1 - phenanthryl, 2 - phenanthryl, 3 - phenanthryl, 4 - phenanthryl, 9 - phenanthryl, and the like.

[0112] In formula (1), Z1 is preferably represented by the following formula (3 - 1) or formula (3 - 2).

[0113]

[0114] (In formula (3 - 1), Q3 represents the following formula (4), formula (5), formula (6), or formula (7).

[0115] * Each represents the bonding part with U in formula (1).)

[0116]

[0117] (In formula (4), formula (5), formula (6), and formula (7),

[0118] R 11 ~R 15 Each independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom, an alkenyl group having 2 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom, an alkynyl group having 2 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom, a benzyl group or a phenyl group, and the phenyl group may be substituted with at least one monovalent functional group selected from an alkyl group having 1 to 6 carbon atoms, a halogen atom, an alkoxy group having 1 to 10 carbon atoms, a nitro group, a cyano group, and an alkylthio group having 1 to 6 carbon atoms.

[0119] * represents a bonding site, *1 represents a bonding site bonded to the nitrogen atom in formula (3-1), *2 represents a bonding site bonded to the carbon atom in formula (3-1), and *3 represents a bonding moiety to U in formula (1).)

[0120] In the present specification, examples of the alkyl group include methyl, ethyl, n-propyl, isopropyl, cyclopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, cyclobutyl, 1-methyl-cyclopropyl, 2-methyl-cyclopropyl, n-pentyl, 1-methyl-n-butyl, 2-methyl-n-butyl, 3-methyl-n-butyl, 1,1-dimethyl-n-propyl, 1,2-dimethyl-n-propyl, 2,2-dimethyl-n-propyl, 1-ethyl-n-propyl, cyclopentyl, 1-methyl-cyclobutyl, 2-methyl-cyclobutyl, 3-methyl-cyclobutyl, 1,2-dimethyl-cyclopropyl, 2,3-dimethyl-cyclopropyl, 1-ethyl-cyclopropyl, 2-ethyl-cyclopropyl, n-hexyl, 1-methyl-n-pentyl, 2-methyl-n-pentyl, 3-methyl-n-pentyl, 4-methyl-n-pentyl, 1,1-dimethyl-n-butyl, 1,2-dimethyl-n-butyl, 1,3-dimethyl-n-butyl, 2,2-dimethyl-n-butyl, 2,3-dimethyl-n-butyl, 3,3-dimethyl-n-butyl, 1-ethyl-n-butyl, 2-ethyl-n-butyl, 1,1,2-trimethyl-n-propyl, 1,2,2-trimethyl-n-propyl, 1-ethyl-1-methyl-n-propyl, 1-ethyl-2-methyl-n-propyl, cyclohexyl, 1-methyl-cyclopentyl, 2-methyl-cyclopentyl, 3-methyl-cyclopentyl, 1-ethyl-cyclobutyl, 2-ethyl-cyclobutyl, 3-ethyl-cyclobutyl, 1,2-dimethyl-cyclobutyl, 1,3-dimethyl-cyclobutyl, 2,2-dimethyl-cyclobutyl, 2,3-dimethyl-cyclobutyl, 2,4-dimethyl-cyclobutyl, 3,3-dimethyl-cyclobutyl, 1-n-propyl-cyclopropyl, 2-n-propyl-cyclopropyl, 1-isopropyl-cyclopropyl, 2-isopropyl-cyclopropyl, 1,2,2-trimethyl-cyclopropyl, 1,2,3-trimethyl-cyclopropyl, 2,2,3-trimethyl-cyclopropyl, 1-ethyl-2-methyl-cyclopropyl, 2-ethyl-1-methyl-cyclopropyl, 2-ethyl-2-methyl-cyclopropyl, 2-ethyl-3-methyl-cyclopropyl, decyl, and the like.

[0121] In this specification, examples of the alkenyl group include 1-propenyl, 2-propenyl, 1-methyl-1-ethenyl, 1-butenyl, 2-butenyl, 3-butenyl, 2-methyl-1-propenyl, 2-methyl-2-propenyl, 1-ethyl-ethenyl, 1-methyl-1-propenyl, 1-methyl-2-propenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 1-n-propyl-ethenyl, 1-methyl-1-butenyl, 1-methyl-2-butenyl, 1-methyl-3-butenyl, 2-ethyl-2-propenyl, 2-methyl-1-butenyl, 2-methyl-2-butenyl, 2-methyl-3-butenyl, 3-methyl-1-butenyl, 3-methyl-2-butenyl, 3-methyl-3-butenyl, 1,1-dimethyl-2-propenyl, 1-isopropyl-ethenyl, 1,2-dimethyl-1-propenyl, 1,2-dimethyl-2-propenyl, 1-cyclopentenyl, 2-cyclopentenyl, 3-cyclopentenyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl, 5-hexenyl, 1-methyl-1-pentenyl, 1-methyl-2-pentenyl, 1-methyl-3-pentenyl, 1-methyl-4-pentenyl, 1-n-butyl-ethenyl, 2-methyl-1-pentenyl, 2-methyl-2-pentenyl, 2-methyl-3-pentenyl, 2-methyl-4-pentenyl, 2-n-propyl-2-propenyl, 3-methyl-1-pentenyl, 3-methyl-2-pentenyl, 3-methyl-3-pentenyl, 3-methyl-4-pentenyl, 3-ethyl-3-butenyl, 4-methyl-1-pentenyl, 4-methyl-2-pentenyl, 4-methyl-3-pentenyl, 4-methyl-4-pentenyl, 1,1-dimethyl-2-butenyl, 1,1-dimethyl-3-butenyl, 1,2-dimethyl-1-butenyl, 1,2-dimethyl-2-butenyl, 1,2-dimethyl-3-butenyl, 1-methyl-2-ethyl-2-propenyl, 1-sec-butyl-ethenyl, 1,3-dimethyl-1-butenyl, 1,3-dimethyl-2-butenyl, 1,3-dimethyl-3-butenyl, 1-isobutyl-ethenyl, 2,2-dimethyl-3-butenyl, 2,3-dimethyl-1-butenyl, 2,3-dimethyl-2-butenyl, 2,3-dimethyl-3-butenyl, 2-isopropyl-2-propenyl, 3,3-dimethyl-1-butenyl, 1-ethyl-1-butenyl, 1-ethyl-2-butenyl, 1-ethyl-3-butenyl, 1-n-propyl-1-propenyl, 1-n-propyl-2-propenyl, 2-ethyl-1-butenyl, 2-ethyl-2-butenyl, 2-ethyl-3-butenyl, 1,1,2-trimethyl-2-propenyl, 1-tert-butylvinyl, 1-methyl-1-ethyl-2-propenyl, 1-ethyl-2-methyl-1-propenyl, 1-ethyl-2-methyl-2-propenyl, 1-isopropyl-1-propenyl, 1-isopropyl-2-propenyl, 1-methyl-2-cyclopentenyl, 1-methyl-3-cyclopentenyl, 2-methyl-1-cyclopentenyl, 2-methyl-2-cyclopentenyl, 2-methyl-3-cyclopentenyl, 2-methyl-4-cyclopentenyl, 2-methyl-5-cyclopentenyl, 2-methylene-cyclopentyl, 3-methyl-1-cyclopentenyl, 3-methyl-2-cyclopentenyl, 3-methyl-3-cyclopentenyl, 3-methyl-4-cyclopentenyl, 3-methyl-5-cyclopentenyl, 3-methylene-cyclopentyl, 1-cyclohexenyl, 2-cyclohexenyl, 3-cyclohexenyl, etc.,

[0122] In the present specification, examples of the alkynyl group include ethynyl, 1-propynyl, 2-propynyl, 1-butynyl, 2-butynyl, 3-butynyl, etc.,

[0123] In the present specification, examples of the halogen atom include fluorine atom, chlorine atom, bromine atom, and iodine atom.,

[0124] In the present specification, examples of the alkoxy group include methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, n-pentyloxy, 1-methyl-n-butoxy, 2-methyl-n-butoxy, 3-methyl-n-butoxy, 1,1-dimethyl-n-propoxy, 1,2-dimethyl-n-propoxy, 2,2-dimethyl-n-propoxy, 1-ethyl-n-propoxy, n-hexyloxy, 1-methyl-n-pentyloxy, 2-methyl-n-pentyloxy, 3-methyl-n-pentyloxy, 4-methyl-n-pentyloxy, 1,1-dimethyl-n-butoxy, 1,2-dimethyl-n-butoxy, 1,3-dimethyl-n-butoxy, 2,2-dimethyl-n-butoxy, 2,3-dimethyl-n-butoxy, 3,3-dimethyl-n-butoxy, 1-ethyl-n-butoxy, 2-ethyl-n-butoxy, 1,1,2-trimethyl-n-propoxy, 1,2,2-trimethyl-n-propoxy, 1-ethyl-1-methyl-n-propoxy, 1-ethyl-2-methyl-n-propoxy, n-heptyloxy, n-octyloxy, n-nonyloxy, etc.,

[0125] In the present specification, examples of the alkylthio group include methylthio, ethylthio, butylthio, etc.,

[0126] In formula (3-1), when Q3 represents formula (4), R in formula (4) 11 and R 12 are each preferably independently an alkyl group having 1 to 10 carbon atoms.,

[0127] In formula (3-1), when Q3 represents formula (5), R in formula (5) 13 and R 14 are each preferably independently an alkyl group having 1 to 10 carbon atoms.

[0128] As Z1 in formula (1), formula (3-1) is preferred.

[0129] Q3 in formula (3-1) is preferably formula (6) or formula (7).

[0130] R in formula (6) 15 is preferably an alkyl group having 1 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom, or an alkenyl group having 2 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom, more preferably an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms.

[0131] The compound represented by formula (1) can be obtained, for example, by reacting the epoxy group or allyl group of the compounds represented by the following formulas (A) to (ak) with 1-thioglycerol (3-mercapto-1,2-propanediol, CAS No. 96-27-5) by a known method, but is not limited thereto. Further, a diol structure obtained by hydrolysis of the epoxy group of the above compound may be included. A diol structure derived from the reaction of the above epoxy group or allyl group with 1-thioglycerol is preferred, and a diol structure derived from the reaction of the above epoxy group with 1-thioglycerol is more preferred.

[0132]

[0133]

[0134] If several specific examples of the compound represented by formula (1) are given, they are as follows. The synthesis method is described in detail in the Examples section.

[0135] · Theoretical molecular weight of the compound represented by formula (X-1): 799

[0136] · Theoretical molecular weight of the compound represented by formula (X-2): 621

[0137] · Theoretical molecular weight of the compound represented by formula (X-3): 471

[0138] · Theoretical molecular weight of the compound represented by formula (X-4): 499

[0139] · Theoretical molecular weight of the compound represented by formula (X-5): 456

[0140] · Theoretical molecular weight of the compound represented by formula (X-6): 573

[0141] ·Theoretical molecular weight of the compound represented by formula (X-7): 795

[0142]

[0143]

[0144] The theoretical molecular weight of the compound represented by formula (1) is 400 to 999, preferably 450 to 800.

[0145] <Component (B)>

[0146] Component (B) is at least any one of a triazole compound (B-1), a tetrazole compound (B-2), a compound (B-3) having two or more phenolic hydroxyl groups, and a compound (B-4) having two or more non-phenolic hydroxyl groups.

[0147] <<Triazole compound (B-1)>>

[0148] As the triazole compound (B-1), there is no particular limitation as long as it is a compound having a triazine ring.

[0149] As for the number of triazine rings in the triazole compound (B-1), there is no particular limitation, and it may be 1, 2, 3, or 4 or more.

[0150] As for the molecular weight of the triazole compound (B-1), there is no particular limitation. For example, it may be 69 to 1,000, 69 to 800, or 69 to 600.

[0151] It should be noted that the molecular weight of triazine (C2H3N3) is 69.

[0152] The triazole compound (B-1) may be a salt or may not be a salt.

[0153] As the triazole compound (B-1), from the viewpoint of appropriately obtaining the effects of the present invention, it is preferably at least any one of the compounds represented by the following formula (B-1-1), the compounds represented by the following formula (B-1-2), the compounds represented by the following formula (B-1-3), and the compounds represented by the following formula (B-1-4).

[0154]

[0155] (In formulas (B-1-1) to (B-1-4), R 11 ~R 20 each independently represents a group formed by one or more atoms selected from a hydrogen atom, a carbon atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, a silicon atom, and a halogen atom.

[0156] R 14 and R 15 can together form a ring structure.

[0157] m and n each independently represent an integer from 0 to 4.

[0158] When m is 2 or more, two or more Rs 18 can be the same or different.

[0159] When n is 2 or more, two or more Rs 20 can be the same or different.)

[0160] As R 11 to R 20 the molecular weight has no particular limitation, for example, it can be 1 to 500, or it can be 1 to 300.

[0161] As the ring structure formed by R 14 and R 15 for example, a 5-membered ring, a 6-membered ring, etc. can be cited.

[0162] As the ring structure formed by R 14 and R 15 for example, a ring structure having a heteroatom can be cited. As the ring structure having a heteroatom, for example, the following ring structures can be cited.

[0163]

[0164] As R 11 to R 20 for example, a hydrogen atom, a halogen atom, a hydroxyl group, a mercapto group, a carboxyl group, an amino group, an amide group, -NO2, -SO3H, a hydrocarbon group which may have a substituent, etc. can be cited.

[0165] As the triazole compound (B-1), for example, the following compounds can be cited.

[0166]

[0167]

[0168] <<tetrazole compound (B-2)>>

[0169] As the tetrazole compound (B-2), as long as it is a compound having a tetrazine ring, there is no particular limitation.

[0170] As the number of tetrazine rings possessed by the tetrazole compound (B-2), there is no particular limitation, and it can be 1, it can be 2, it can be 3, or it can be 4 or more.

[0171] The molecular weight of the tetrazole compound (B-2) is not particularly limited. For example, it can be 70 to 1,000, it can be 69 to 800, it can be 69 to 600, or it can be 69 to 400.

[0172] It should be noted that the molecular weight of tetrazine (CH2N4) is 70.

[0173] The tetrazole compound (B-2) can be a salt or not a salt.

[0174] As the tetrazole compound (B-2), from the viewpoint of appropriately obtaining the effects of the present invention, the compound represented by the following formula (B-2-1) is preferred.

[0175]

[0176] (In formula (B-2-1), R 21 and R 22 each independently represent a group formed by one or more atoms selected from a hydrogen atom, a carbon atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, a silicon atom, and a halogen atom.

[0177] R 21 and R 22 can together form a ring structure.)

[0178] As the molecular weight of R 21 and R 22 is not particularly limited. For example, it can be 1 to 500, or it can be 1 to 300.

[0179] As the ring structure formed by R 21 and R 22 together, for example, a 5-membered ring, a 6-membered ring, a 7-membered ring, etc. can be mentioned.

[0180] As the ring structure formed by R 21 and R 22 together, for example, a ring structure having a heteroatom can be mentioned. As the ring structure having a heteroatom, for example, the following 7-membered ring structure can be mentioned.

[0181]

[0182] It should be noted that the N in the formula is the N constituting the tetrazine ring.

[0183] As R 21 and R 22 , for example, a hydrogen atom, a halogen atom, a hydroxyl group, a mercapto group, a carboxyl group, an amino group, an amide group, -NO2, -SO3H, a hydrocarbon group which may have a substituent, etc. can be mentioned.

[0184] As the tetrazole compound (B-2), for example, the following compounds can be mentioned.

[0185]

[0186]

[0187] <<Compound (B-3) having two or more phenolic hydroxyl groups>>

[0188] As the compound (B-3) having two or more phenolic hydroxyl groups (hereinafter sometimes referred to as compound (B-3)), there is no particular limitation.

[0189] As the molecular weight of the compound (B-3), there is no particular limitation. For example, it can be 110 to 1,500, it can be 110 to 1,000, it can be 110 to 800, or it can be 110 to 400.

[0190] It should be noted that the molecular weight of dihydroxybenzene is 110.

[0191] As the compound (B-3), from the viewpoint of appropriately obtaining the effects of the present invention, it is preferably at least any one of the compound (B-3-1) represented by the following formula (11a), the compound (B-3-2) represented by the following formula (11b), and the compound having a group represented by the following formula (12) and having a molecular weight of 300 or more and less than 800 or a compound (B-3-3) having a weight average molecular weight of 300 or more and less than 800.

[0192]

[0193] (In formulas (11a), (11b) and (12), R 31 represents a single bond, an alkylene group having 1 to 4 carbon atoms, or an alkenylene group having 2 to 4 carbon atoms.

[0194] k represents an integer 0 or 1.

[0195] m represents an integer 1 to 3.

[0196] n represents an integer 2 to 4.

[0197] * represents a bonding site.)

[0198] As the compound (B-3-1) represented by the formula (11a), for example, the compounds represented by the following formula (11a-1) to the compounds represented by the formula (11a-19) can be mentioned.

[0199]

[0200] As the compound (B-3-2) represented by the formula (11b), examples thereof include compounds represented by the following formula (11b-1) to compounds represented by the formula (11b-31).

[0201]

[0202]

[0203] A compound having a group represented by the formula (12) and having a molecular weight of 300 or more and less than 800, or a compound (B-3-3) having a weight-average molecular weight of 300 or more and less than 800 (hereinafter sometimes referred to as compound (B-3-3)) can be any one of a monomer, a dimer, a trimer, and an oligomer.

[0204] Examples of the group represented by the formula (12) include groups represented by the following formula (21-1) to groups represented by the formula (21-14).

[0205]

[0206] (In the formula, * represents a bonding bond.)

[0207] Examples of the compound (B-3-3) include compounds represented by the following formula (21a-1) to compounds represented by the formula (21a-3).

[0208]

[0209] <<Compound (B-4) having two or more non-phenolic hydroxyl groups>>

[0210] The compound (B-4) having two or more non-phenolic hydroxyl groups (hereinafter sometimes referred to as compound (B-4)) is not particularly limited.

[0211] The molecular weight of the compound (B-4) is not particularly limited. For example, it can be 106 to 500, it can be 106 to 400, or it can be 106 to 300.

[0212] From the viewpoint of appropriately obtaining the effects of the present invention, the compound (B-4) is preferably a compound represented by the following formula (B-4-1).

[0213]

[0214] (In the formula (B-4-1), X represents -O- or -NR- (R represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms which may have a hydroxyl group, an aryl group having 6 to 12 carbon atoms which may have a substituent, or an aralkyl group having 7 to 13 carbon atoms which may have a substituent).)

[0215] n represents an integer from 1 to 3. When n is 2 or 3, X may be the same or different. )

[0216] As the aromatic ring in the aryl group having 6 to 12 carbon atoms which may have a substituent, for example, a benzene ring, a naphthalene ring, etc. can be cited.

[0217] As the aromatic ring in the aralkyl group having 7 to 13 carbon atoms which may have a substituent, for example, a benzene ring, a naphthalene ring, etc. can be cited.

[0218] As the substituents in the aryl group having 6 to 12 carbon atoms which may have a substituent and the aralkyl group having 7 to 13 carbon atoms which may have a substituent, for example, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, etc. can be cited.

[0219] As R in -NR- of formula (B-4-1), an alkyl group having 1 to 6 carbon atoms which may have a hydroxyl group and an aryl group having 6 to 12 carbon atoms which may have a substituent are preferred. As the alkyl group having 1 to 6 carbon atoms which may have a hydroxyl group, a hydroxyalkyl group is preferred, and 2-hydroxyethyl is more preferred.

[0220] In formula (B-4-1), when X is -O-, n is preferably 2.

[0221] In formula (B-4-1), when X is -NR-, n is preferably 1.

[0222] As the compound (B-4), for example, the following compounds, etc. can be cited.

[0223]

[0224] The content of the component (B) in the protective film-forming composition is not particularly limited, but from the viewpoint of appropriately obtaining the effects of the present invention, it is preferably 0.01 part by mass to 50 parts by mass, more preferably 0.1 part by mass to 10 parts by mass, and particularly preferably 0.5 part by mass to 5 parts by mass with respect to 100 parts by mass of the component (A).

[0225] <Curing catalyst>

[0226] As the curing catalyst contained as an optional component in the protective film-forming composition, either a thermal acid generator or a photoacid generator can be used, but a thermal acid generator is preferably used.

[0227] 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 phenolsulfonate, pyridinium p-hydroxybenzenesulfonate (pyridinium p-phenolsulfonate), pyridinium trifluoromethanesulfonate, salicylic acid, camphorsulfonic acid, 5-sulfosalicylic acid, 4-chlorobenzenesulfonic acid, 4-hydroxybenzenesulfonic acid, benzenedisulfonic acid, 1-naphthalenesulfonic acid, citric acid, benzoic acid, and hydroxybenzoic acid.

[0228] Examples of the photoacid generator include onium salt compounds, sulfonimide compounds, and disulfonyldiazomethane compounds.

[0229] Examples of the onium salt compounds include iodonium salt compounds such as diphenyliodonium hexafluorophosphate, diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluorobutanesulfonate, diphenyliodonium perfluorooctanesulfonate, diphenyliodonium camphorsulfonate, bis(4-tert-butylphenyl)iodonium camphorsulfonate, and bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate; and sulfonium salt compounds such as triphenylsulfonium hexafluoroantimonate, triphenylsulfonium nonafluorobutanesulfonate, triphenylsulfonium camphorsulfonate, and triphenylsulfonium trifluoromethanesulfonate.

[0230] Examples of the sulfonimide compounds include N-(trifluoromethanesulfonyloxy)succinimide, N-(nonafluorobutanesulfonyloxy)succinimide, N-(camphorsulfonyloxy)succinimide, and N-(trifluoromethanesulfonyloxy)naphthalimide.

[0231] Examples of the disulfonyldiazomethane compounds include bis(trifluoromethylsulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, bis(phenylsulfonyl)diazomethane, bis(p-toluenesulfonyl)diazomethane, bis(2,4-dimethylphenylsulfonyl)diazomethane, and methylsulfonyl-p-toluenesulfonyldiazomethane.

[0232] The curing catalyst may be used alone or in combination of two or more.

[0233] When using the curing catalyst, the content ratio of the curing catalyst is, for example, 0.1% by mass to 50% by mass, preferably 1% by mass to 30% by mass, relative to the component (A).

[0234] <(C) Solvent>

[0235] The composition for forming a protective film of the present invention can be prepared by dissolving the above components in a solvent, preferably an organic solvent, and used in a homogeneous solution state.

[0236] As the organic solvent of the composition for forming a protective film according to the present invention, any organic solvent that can dissolve solid components such as component (A), component (B), and other optional solid components can be used without particular limitation. In particular, since the composition for forming a protective film according to the present invention is used in a uniform solution state, if its coating performance is considered, it is recommended to use in combination an organic solvent commonly used in the lithography process.

[0237] Examples of the organic solvent 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 monoethyl ether, propylene glycol monomethyl ether acetate, propylene glycol propyl ether acetate, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, cycloheptanone, 4-methyl-2-pentanol, ethyl ethoxyacetate, 2-hydroxyethyl acetate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, 2-heptanone, methoxycyclopentane, anisole, γ-butyrolactone, N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide. These solvents can be used alone or in combination of two or more.

[0238] Among these solvents, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, cyclohexanone, etc. are preferred. Propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate are particularly preferred.

[0239] The solid content of the composition for forming a protective film according to the present invention is usually 0.1 to 70% by mass, preferably 0.1 to 60% by mass. The solid content is the content ratio of all components obtained by removing the solvent from the composition for forming a protective film. The proportion of component (A) in the solid content is preferably 1 to 99.9% by mass, more preferably 50 to 99.9% by mass, still more preferably 50 to 95% by mass, and particularly preferably 50 to 90% by mass.

[0240] (Method for manufacturing a protective film, a substrate with a protective film, a substrate with a resist pattern, and a semiconductor device)

[0241] The protective film of the present invention is a fired product of a coating film formed from the composition for forming a protective film.

[0242] The method for manufacturing a substrate with a protective film according to the present invention includes a step of coating the composition for forming a protective film of the present invention on a semiconductor substrate having a height difference and firing to form a protective film.

[0243] The method for manufacturing a substrate with a resist pattern according to the present invention includes the following steps (1) to (2).

[0244] Step (1): A step of coating the composition for forming a protective film of the present invention on a semiconductor substrate and firing it to form a protective film as an underlayer film for a resist

[0245] Step (2): A step of forming a resist film directly on the protective film or via another layer, and then performing exposure and development to form a resist pattern

[0246] The method for manufacturing a semiconductor device of the present invention includes the following treatments (A) to (D).

[0247] Treatment (A): A treatment of forming a protective film on a semiconductor substrate having an inorganic film formed on its surface using the composition for forming a protective film of the present invention

[0248] Treatment (B): A treatment of forming a resist pattern directly on the protective film or via another layer

[0249] Treatment (C): A treatment of dry-etching the protective film using the resist pattern as a mask to expose the surface of the inorganic film

[0250] Treatment (D): A treatment of wet-etching the inorganic film using a wet etching solution for semiconductors with the protective film after dry-etching as a mask

[0251] Examples of the semiconductor substrate for coating the composition for forming a protective film of the present invention (composition for forming an underlayer film for a resist) include silicon wafers, germanium wafers, and compound semiconductor wafers such as gallium arsenide, indium phosphide, gallium nitride, indium nitride, and aluminum nitride.

[0252] In the case of using a semiconductor substrate having an inorganic film formed on its surface, the inorganic film is formed, for example, by an ALD (Atomic Layer Deposition) method, a CVD (Chemical Vapor Deposition) method, a reactive sputtering method, an ion plating method, a vacuum evaporation method, or a spin coating method (spin-on glass: SOG). Examples of the above inorganic film include a polysilicon film, a silicon oxide film, a silicon nitride film, a silicon oxynitride film, a boron phosphosilicate glass (BPSG) film, a titanium nitride film, a titanium oxynitride film, a tungsten nitride film, a gallium nitride film, and a gallium arsenide film.

[0253] The above semiconductor substrate can be a substrate with height differences formed with so-called vias (holes), trenches (grooves), etc. For example, in the case of a via, when viewed from above, it has a substantially circular shape, and the diameter of the approximate circle is, for example, 2 nm to 20 nm, and the depth is 50 nm to 500 nm. The composition for forming a protective film (composition for forming an underlayer film for a resist) of the present invention can be buried in the substrate with height differences as described above without defects such as voids (gaps) because the weight average molecular weight and average particle size of the compounds contained in the composition are small. For subsequent processes in semiconductor manufacturing (wet etching / dry etching of a semiconductor substrate, formation of a resist pattern), the absence of defects such as voids is an important characteristic.

[0254] On such a semiconductor substrate, the composition for forming a protective film of the present invention is coated by an appropriate coating method such as a spinner or a coater. Then, baking is performed using a heating means such as a hot plate to form a protective film. As the baking conditions, appropriate selection is made from a baking temperature of 100°C to 400°C and a baking time of 0.3 minutes to 60 minutes. Preferably, the baking temperature is 120°C to 350°C and the baking time is 0.5 minutes to 30 minutes, and more preferably, the baking temperature is 150°C to 300°C and the baking time is 0.8 minutes to 10 minutes. As the film thickness of the formed protective film, for example, it is 0.001 μm to 10 μm, preferably 0.002 μm to 1 μm, and more preferably 0.005 μm to 0.5 μm. When the temperature during baking is lower than the above range, crosslinking may sometimes be insufficient, and it is difficult to obtain the resistance of the formed protective film to a resist solvent or an alkaline hydrogen peroxide aqueous solution. On the other hand, when the temperature during baking is higher than the above range, the protective film may sometimes decompose due to heat.

[0255] On the protective film formed as described above, a resist film is formed directly or via another layer, and then exposure and development are performed to form a resist pattern.

[0256] Exposure is performed through a mask (reticle) for forming a prescribed pattern, using, for example, i-ray, KrF excimer laser, ArF excimer laser, EUV (extreme ultraviolet), or EB (electron beam). Development is carried out using an alkaline developer, and appropriate selection is made from a development temperature of 5°C to 50°C and a development time of 10 seconds to 300 seconds. As the alkaline developer, for example, inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and ammonia water, primary amines such as ethylamine and n-propylamine, secondary amines such as diethylamine and di-n-butylamine, tertiary amines such as triethylamine and methyldiethylamine, alkanolamines such as dimethylethanolamine and triethanolamine, quaternary ammonium salts such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, and choline, and cyclic amines such as pyrrole and piperidine can be used. Further, an appropriate amount of alcohols such as isopropyl alcohol and surfactants such as nonionic surfactants can be added to the aqueous solution of the above-mentioned alkalis for use. Among them, the preferred developer is a quaternary ammonium salt, and more preferably tetramethylammonium hydroxide and choline. Further, a surfactant or the like can be added to these developers. Instead of the alkaline developer, development can also be carried out using an organic solvent such as butyl acetate, and a method of developing the portion where the base dissolution rate of the photoresist is not increased can be used.

[0257] Next, the formed resist pattern is used as a mask to perform dry etching on the protective film. At this time, when the inorganic film is formed on the surface of the semiconductor substrate used, the surface of the inorganic film is exposed, and when the inorganic film is not formed on the surface of the semiconductor substrate used, the surface of the semiconductor substrate is exposed.

[0258] Further, the protective film after dry etching (when the resist pattern remains on the protective film, the resist pattern as well) is used as a mask, and wet etching is performed using a semiconductor wet etching solution to form a desired pattern.

[0259] As the semiconductor wet etching solution, general chemical solutions for etching semiconductor wafers can be used, for example, substances showing acidity and substances showing alkalinity can both be used.

[0260] Examples of substances showing acidity include hydrogen peroxide, hydrofluoric acid, ammonium fluoride, acidic ammonium fluoride, ammonium bifluoride, buffered hydrofluoric acid, hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, or a mixture thereof.

[0261] As a substance showing alkalinity, alkaline hydrogen peroxide water obtained by mixing ammonia, sodium hydroxide, potassium hydroxide, sodium cyanide, potassium cyanide, an organic amine such as triethanolamine with hydrogen peroxide water to make the pH alkaline can be mentioned. As a specific example, SC-1 (ammonia-hydrogen peroxide solution) can be mentioned. In addition, a substance that can make the pH alkaline, for example, a substance obtained by mixing urea with hydrogen peroxide water and causing thermal decomposition of urea by heating to generate ammonia and finally making the pH alkaline can also be used as a wet etching liquid.

[0262] Among them, acidic hydrogen peroxide water or alkaline hydrogen peroxide water is preferred.

[0263] These liquid medicines can contain additives such as surfactants.

[0264] The use temperature of the wet etching liquid for semiconductors is desirably 25°C to 90°C, and more desirably 40°C to 80°C. As the wet etching time, it is desirably 0.5 minute to 30 minutes, and more desirably 1 minute to 20 minutes.

[0265] Examples

[0266] Next, examples are given to specifically illustrate the content of the present invention, but the present invention is not limited thereto.

[0267] The weight average molecular weight of the reaction products shown in Synthesis Examples 1 to 3 below in this specification is the measurement result obtained by gel permeation chromatography (hereinafter, simply referred to as GPC). The measurement uses a GPC device manufactured by Tosoh Corporation, and the measurement conditions are as follows.

[0268] · Column temperature: 40°C

[0269] · Solvent: Tetrahydrofuran (THF)

[0270] · Flow rate: 1.0 ml / minute

[0271] · Standard sample: Polystyrene (manufactured by Tosoh Corporation)

[0272] <Synthesis Example 1>

[0273] A reaction flask containing 30.0 g of diglycidyl methyl isocyanurate (product name: MeDGIC, manufactured by Shikoku Kasei Kogyo Co., Ltd., 29.9 wt% propylene glycol monomethyl ether solution), 7.9 g of 1-thioglycerol (manufactured by Asahi Chemical Industry Co., Ltd.), and 0.9 g of tetrabutylphosphonium bromide (manufactured by Kitakyo Chemical Co., Ltd.) with 50.2 g of propylene glycol monomethyl ether added was heated and stirred at 100°C for 16 hours under a nitrogen atmosphere. The obtained reaction product corresponds to formula (X-1), and the weight average molecular weight Mw measured in terms of polystyrene obtained by GPC is 460.

[0274] Formula (X-1)

[0275]

[0276] <Synthesis Example 2>

[0277] A reaction flask containing 9.0 g of monoallyl diglycidyl isocyanurate (manufactured by Shikoku Chemicals Corporation, product name MA-DGIC), 7.1 g of 1-thioglycerol (manufactured by Asahi Chemical Industry Co., Ltd.), and 0.82 g of tetrabutylphosphonium bromide (manufactured by Kitakyo Chemical Co., Ltd.) was added with 67.7 g of propylene glycol monomethyl ether and heated with stirring at 100 °C for 16 hours under a nitrogen atmosphere. The resulting reaction product corresponded to formula (X-2), and the weight-average molecular weight Mw measured in terms of polystyrene by GPC was 491.

[0278] Formula (X-2)

[0279]

[0280] <Synthesis Example 3>

[0281] A reaction flask containing 13.0 g of triglycidyl isocyanurate (product name TEPIC, manufactured by Nissan Chemical Industries, Ltd.), 14.3 g of 1-thioglycerol (manufactured by Asahi Chemical Industry Co., Ltd.), and 1.7 g of tetrabutylphosphonium bromide (manufactured by Kitakyo Chemical Co., Ltd.) was added with 115.9 g of propylene glycol monomethyl ether and heated with stirring at 100 °C for 16 hours under a nitrogen atmosphere. The resulting reaction product corresponded to formula (X-3), and the weight-average molecular weight Mw measured in terms of polystyrene by GPC was 587.

[0282] Formula (X-3)

[0283]

[0284] <Example 1>

[0285] To 5.1 g of the solution containing the reaction product obtained in Synthesis Example 1, 0.029 g of pyridinium trifluoromethanesulfonate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0076 g of gallic acid hydrate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0008 g of a surfactant (product name: Megafac R-40, manufactured by DIC Corporation), 1.9 g of propylene glycol monomethyl ether acetate, and 13.0 g of propylene glycol monomethyl ether were added to prepare a solution. The solution was filtered through a polyethylene microfilter with a pore size of 0.02 μm to prepare a composition for forming a protective film.

[0286] <Example 2>

[0287] To 5.1 g of the solution containing the reaction product obtained in Synthesis Example 1, 0.029 g of pyridinium trifluoromethanesulfonate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0076 g of 1,2,3-benzotriazole (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0008 g of a surfactant (product name: Megafac R-40, manufactured by DIC Corporation), 1.9 g of propylene glycol monomethyl ether acetate, and 13.0 g of propylene glycol monomethyl ether were added to prepare a solution. The solution was filtered through a polyethylene microfilter with a pore size of 0.02 μm to prepare a composition for forming a protective film.

[0288] <Example 3>

[0289] To 5.1 g of the solution containing the reaction product obtained in Synthesis Example 1, 0.029 g of pyridinium trifluoromethanesulfonate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0076 g of 5-benzyl-1H-tetrazole (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0008 g of a surfactant (product name: Megafac R-40, manufactured by DIC Corporation), 1.9 g of propylene glycol monomethyl ether acetate, and 13.0 g of propylene glycol monomethyl ether were added to prepare a solution. The solution was filtered through a polyethylene microfilter with a pore size of 0.02 μm to prepare a composition for forming a protective film.

[0290] <Example 4>

[0291] To 5.1 g of the solution containing the reaction product obtained in Synthesis Example 1, 0.029 g of pyridinium trifluoromethanesulfonate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0076 g of triethanolamine (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0008 g of a surfactant (product name: Megafac R-40, manufactured by DIC Corporation), 1.9 g of propylene glycol monomethyl ether acetate, and 13.0 g of propylene glycol monomethyl ether were added to prepare a solution. The solution was filtered through a polyethylene microfilter with a pore size of 0.02 μm to prepare a composition for forming a protective film.

[0292] <Example 5>

[0293] To 5.1 g of the solution containing the reaction product obtained in Synthesis Example 1, 0.029 g of pyridinium trifluoromethanesulfonate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0076 g of N-phenyldiethanolamine (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0008 g of a surfactant (product name: Megafac R-40, manufactured by DIC Corporation), 1.9 g of propylene glycol monomethyl ether acetate, and 13.0 g of propylene glycol monomethyl ether were added to prepare a solution. The solution was filtered through a polyethylene microfilter with a pore size of 0.02 μm to prepare a composition for forming a protective film.

[0294] <Example 6>

[0295] To 4.9 g of the solution containing the reaction product obtained in Synthesis Example 2, 0.029 g of pyridinium trifluoromethanesulfonate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0076 g of gallic acid hydrate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0008 g of a surfactant (product name: Megafac R-40, manufactured by DIC Corporation), 1.9 g of propylene glycol monomethyl ether acetate, and 13.1 g of propylene glycol monomethyl ether were added to prepare a solution. The protective film-forming composition was prepared by filtering this solution through a polyethylene microfilter with a pore size of 0.02 μm.

[0296] <Example 7>

[0297] To 4.9 g of the solution containing the reaction product obtained in Synthesis Example 2, 0.029 g of pyridinium trifluoromethanesulfonate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0076 g of 3-mercapto-1,2,4-triazole (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0008 g of a surfactant (product name: Megafac R-40, manufactured by DIC Corporation), 1.9 g of propylene glycol monomethyl ether acetate, and 13.1 g of propylene glycol monomethyl ether were added to prepare a solution. The protective film-forming composition was prepared by filtering this solution through a polyethylene microfilter with a pore size of 0.02 μm.

[0298] <Example 8>

[0299] To 4.9 g of the solution containing the reaction product obtained in Synthesis Example 2, 0.029 g of pyridinium trifluoromethanesulfonate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0076 g of 3-mercapto-4-methyl-4H-1,2,4-triazole (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0008 g of a surfactant (product name: Megafac R-40, manufactured by DIC Corporation), 1.9 g of propylene glycol monomethyl ether acetate, and 13.1 g of propylene glycol monomethyl ether were added to prepare a solution. The protective film-forming composition was prepared by filtering this solution through a polyethylene microfilter with a pore size of 0.02 μm.

[0300] <Example 9>

[0301] To 4.9 g of the solution containing the reaction product obtained in Synthesis Example 2, 0.029 g of pyridinium trifluoromethanesulfonate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0076 g of triethanolamine (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0008 g of a surfactant (product name: Megafac R-40, manufactured by DIC Corporation), 1.9 g of propylene glycol monomethyl ether acetate, and 13.1 g of propylene glycol monomethyl ether were added to prepare a solution. The solution was filtered through a polyethylene microfilter with a pore size of 0.02 μm to prepare a composition for forming a protective film.

[0302] <Example 10>

[0303] To 4.7 g of the solution containing the reaction product obtained in Synthesis Example 3, 0.029 g of pyridinium trifluoromethanesulfonate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0076 g of 5-benzyl-1H-tetrazole (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0008 g of a surfactant (product name: Megafac R-40, manufactured by DIC Corporation), 1.9 g of propylene glycol monomethyl ether acetate, and 13.4 g of propylene glycol monomethyl ether were added to prepare a solution. The solution was filtered through a polyethylene microfilter with a pore size of 0.02 μm to prepare a composition for forming a protective film.

[0304] <Example 11>

[0305] To 4.7 g of the solution containing the reaction product obtained in Synthesis Example 3, 0.029 g of pyridinium trifluoromethanesulfonate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0076 g of N-phenyldiethanolamine (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0008 g of a surfactant (product name: Megafac R-40, manufactured by DIC Corporation), 1.9 g of propylene glycol monomethyl ether acetate, and 13.4 g of propylene glycol monomethyl ether were added to prepare a solution. The solution was filtered through a polyethylene microfilter with a pore size of 0.02 μm to prepare a composition for forming a protective film.

[0306] <Comparative Example 1>

[0307] To 5.1 g of the solution containing the reaction product obtained in Synthesis Example 1, 0.029 g of pyridinium trifluoromethanesulfonate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0008 g of a surfactant (product name: Megafac R-40, manufactured by DIC Corporation), 1.9 g of propylene glycol monomethyl ether acetate, and 12.9 g of propylene glycol monomethyl ether were added to prepare a solution. The solution was filtered through a polyethylene microfilter with a pore size of 0.02 μm to prepare a composition for forming a protective film.

[0308] <Comparative Example 2>

[0309] To 5.0 g of the solution containing the reaction product obtained in Synthesis Example 2, 0.029 g of pyridinium trifluoromethanesulfonate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0008 g of a surfactant (product name: Megafac R-40, manufactured by DIC Corporation), 1.9 g of propylene glycol monomethyl ether acetate, and 13.0 g of propylene glycol monomethyl ether were added to prepare a solution. The solution was filtered through a polyethylene microfilter with a pore size of 0.02 μm to prepare a composition for forming a protective film.

[0310] <Comparative Example 3>

[0311] To 4.7 g of the solution containing the reaction product obtained in Synthesis Example 3, 0.029 g of pyridinium trifluoromethanesulfonate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.0008 g of a surfactant (product name: Megafac R-40, manufactured by DIC Corporation), 1.9 g of propylene glycol monomethyl ether acetate, and 13.3 g of propylene glycol monomethyl ether were added to prepare a solution. The solution was filtered through a polyethylene microfilter with a pore size of 0.02 μm to prepare a composition for forming a protective film.

[0312] <Comparative Example 4>

[0313] To 8.25 g of a solution of the reaction product (corresponding to the following formula (1n), a copolymer having a weight-average molecular weight of 4500 measured in terms of polystyrene obtained by GPC) obtained by the method described in Synthesis Example 12 of WO2020 / 026834 (solid content: 16.4% by mass), 0.05 g of pyridinium trifluoromethanesulfonate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.01 g of a surfactant (product name: Megafac R-40, manufactured by DIC Corporation), 18.05 g of propylene glycol monomethyl ether, and 2.84 g of propylene glycol monomethyl ether acetate were added to prepare a solution. The solution was filtered through a polyethylene microfilter with a pore size of 0.02 μm to prepare a composition for forming a protective film.

[0314]

[0315] The names, abbreviations, and structures of the additives used in Examples 1 to 11 are as follows.

[0316] · Gallic acid (GA)

[0317]

[0318] · 1,2,3-Benzotriazole (BTZ)

[0319]

[0320] · 5-Benzyl-1H-tetrazole (5-BTEZ)

[0321]

[0322] · Triethanolamine (TEA)

[0323]

[0324] · N-Phenyldiethanolamine (PDEA)

[0325]

[0326] · 3-Mercapto-1,2,4-triazole (3-MTZ)

[0327]

[0328] · 3-Mercapto-4-methyl-4H-1,2,4-triazole (3-MMTZ)

[0329]

[0330] The types of reaction products, the types of additives, and the compounding amounts of the additives in Examples 1 to 11 and Comparative Examples 1 to 3 are shown in Table 1. It should be noted that the compounding amounts of the additives in Table 1 are the compounding amounts (parts by mass) relative to 100 parts by mass of the reaction product.

[0331] [Table 1]

[0332]

[0333] (Formation of the coating film)

[0334] [Resistance test to hydrogen peroxide solution]

[0335] As an evaluation of the resistance to hydrogen peroxide solution, the coating compositions for forming a protective film prepared in Examples 1 to 11 and Comparative Examples 1 to 4 were each coated on a titanium nitride (TiN) vapor deposition substrate with a film thickness of 50 nm and heated at 220 °C for 1 minute to form a protective film with a film thickness of 100 nm. Next, 20 mass% hydrogen peroxide solution was prepared. The TiN vapor deposition substrate coated with the above coating composition for forming a protective film was immersed in 20 mass% hydrogen peroxide solution heated to 70 °C, and the time from just after immersion until the coating film (protective film) peeled off was measured. The results of the resistance test to hydrogen peroxide solution are shown in Tables 2-1 to 2-2. "○" in Tables 2-1 to 2-2 indicates that no peeling of the coating film was observed after immersion, and "×" indicates that peeling was observed in part or all of the coating film after immersion.

[0336] [Table 2-1]

[0337]

[0338]

Table 2-2

[0339] Reaction product Results of 15-minute tolerance test Example 10 Synthesis Example 3 ○ Example 11 Synthesis Example 3 ○ Comparative Example 3 Synthesis Example 3 × Comparative Example 4 Formula (1n) × (peeled off in 2 minutes)

[0340] The results in the above Tables 2-1 to 2-2 show that the coatings made using the composition for forming a protective film prepared in Examples 1 to 11 have sufficient resistance to hydrogen peroxide water. That is, it is understood that these coatings can serve as a protective film against hydrogen peroxide water.

[0341] (Test of optical parameters)

[0342] The composition for forming a protective film prepared in Examples 1 to 11 and Comparative Examples 1 to 4 was spin-coated on a silicon wafer, respectively. On a hot plate, it was baked at 220 °C for 1 minute to form a protective film (film thickness: 50 nm). Further, the n value (refractive index) and k value (attenuation coefficient or extinction coefficient) at wavelengths of 193 nm and 248 nm were measured for these films using a spectroscopic ellipsometer (J.A. Woollam, VUV-VASE VU-302). The results are shown in Table 3.

[0343]

Table 3

[0344] n / k @ 193 nm n / k @ 248 nm Example 1 1.93 / 0.27 1.70 / 0 Example 2 1.94 / 0.28 1.71 / 0 Example 3 1.94 / 0.28 1.71 / 0 Example 4 1.94 / 0.27 1.70 / 0 Example 5 1.94 / 0.27 1.70 / 0 Example 6 1.96 / 029 1.71 / 0 Example 7 1.96 / 0.29 1.71 / 0 Example 8 1.96 / 0.29 1.71 / 0 Example 9 1.96 / 028 1.71 / 0 Example 10 1.90 / 0.24 1.71 / 0 Example 11 1.91 / 0.24 1.72 / 0 Comparative Example 1 1.94 / 0.27 1.71 / 0 Comparative Example 2 1.96 / 0.29 1.71 / 0 Comparative Example 3 1.91 / 0.24 1.72 / 0 Comparative Example 4 1.84 / 0.24 1.74 / 0.14

[0345] [Evaluation of etching selectivity]

[0346] As an evaluation of the etching selectivity, the resist underlayer film-forming composition (composition for forming a protective film) prepared in the above Examples 1 to 11 and Comparative Examples 1 to 4 was each coated on a silicon wafer and heated at 220 °C for 1 minute to form a protective film with a film thickness of 100 nm. Next, the formed protective film was dry-etched using a dry etching apparatus (product name: Lam2300, Lam ReseaRch) with a mixed gas of nitrogen and hydrogen, and the ratio of the dry etching rates (etching selectivity of the dry etching rate) of the protective film was measured. The measurement results of the etching selectivity are shown in Table 4. It should be noted that the larger the etching selectivity, the faster the dry etching rate. It should be noted that the results shown in Table 4 are the etching rates when the etching rate of the protective film in Comparative Example 4 is set to 1.0.

[0347]

Table 4

[0348]

[0349] Based on the above results, the dry etching selectivity of Examples 1 to 11 is higher than that of Comparative Example 4, so it can be said that the dry etching speed is fast. That is, since Examples 1 to 11 can shorten the dry etching time required to remove the protective film, damage to the substrate can be reduced, and thus they are useful.

[0350] Industrial applicability

[0351] The composition for forming a protective film according to the present invention has excellent resistance when a wet etching solution is applied to substrate processing and has a high dry etching speed, and thus provides a protective film that is easy to process for the substrate.

Claims

1. A composition for forming a protective film resistant to a wet etching solution for semiconductors, which comprises: Component (A): A film-forming component, Component (B): At least any one of a triazole compound (B-1), a tetrazole compound (B-2), a compound (B-3) having two or more phenolic hydroxyl groups, and a compound (B-4) having two or more non-phenolic hydroxyl groups, and Component (C): A solvent.

2. The composition for forming a protective film according to claim 1, wherein the component (A) comprises a compound having a theoretical molecular weight of 999 or less.

3. The composition for forming a protective film according to claim 2, wherein the compound having a theoretical molecular weight of 999 or less is a compound represented by the following formula (1) and having a theoretical molecular weight of 999 or less. In formula (1), Z1 represents a p-valent group containing a nitrogen-containing heterocycle, p represents an integer of 2 to 4, Each U independently represents a monovalent organic group represented by the following formula (2), In formula (2), R1 represents an alkylene group having 1 to 4 carbon atoms, T represents a single bond or an (s + 1)-valent hydrocarbon group having 1 to 8 carbon atoms, A1 to A3 each independently represent a hydrogen atom, a methyl group or an ethyl group, X represents -COO-, -OCO-, -O-, -S- or -NR a -, R a represents a hydrogen atom or a methyl group, Y represents a single bond or an alkylene group having 1 to 4 carbon atoms which may be substituted, R2, R3 and R4 each independently represent a hydrogen atom, or an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 40 carbon atoms which may be substituted, R5 represents a hydrogen atom or a hydroxyl group, m1, m2 and q each independently represent an integer of 0 or 1, s represents an integer of 1 or 2, * represents the bonding portion with Z1 in formula (1), Among them, When T is a single bond, m1 and q are not both 1.

4. The composition for forming a protective film according to claim 3, wherein Z1 is represented by the following formula (3-1) or formula (3-2). In formula (3-1), Q3 represents the following formula (4), formula (5), formula (6) or formula (7), Each * represents the bonding portion with U in formula (1), In formula (4), formula (5), formula (6) and formula (7), R 11 ~R 15 Each independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom, an alkenyl group having 2 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom, an alkynyl group having 2 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom, a benzyl group or a phenyl group, and the phenyl group may be substituted by at least one monovalent functional group selected from an alkyl group having 1 to 6 carbon atoms, a halogen atom, an alkoxy group having 1 to 10 carbon atoms, a nitro group, a cyano group, and an alkylthio group having 1 to 6 carbon atoms. * represents a bonding bond, *1 represents the bonding bond with the nitrogen atom in formula (3-1), *2 represents the bonding bond with the carbon atom in formula (3-1), and *3 represents the bonding portion with U in formula (1).

5. The composition for forming a protective film according to claim 1, wherein the triazole compound (B-1) is at least any one of a compound represented by the following formula (B-1-1), a compound represented by the following formula (B-1-2), a compound represented by the following formula (B-1-3), and a compound represented by the following formula (B-1-4). In formulas (B-1-1) to (B-1-4), R 11 ~R 20 each independently represents a group formed of one or more atoms selected from a hydrogen atom, a carbon atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, a silicon atom, and a halogen atom, R 14 and R 15 can together form a ring structure m and n each independently represent an integer of 0 to 4. When m is 2 or more, two or more Rs 18 may be the same or different, When n is 2 or more, two or more Rs 20 may be the same or different.

6. The composition for forming a protective film according to claim 1, wherein the tetrazole compound (B-2) is a compound represented by the following formula (B-2-1). In formula (B-2-1), R 21 and R 22 each independently represents a group formed of one or more atoms selected from a hydrogen atom, a carbon atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, a silicon atom, and a halogen atom, R 21 and R 22 can together form a ring structure.

7. The composition for forming a protective film according to claim 1, wherein the compound (B-3) is at least any one of a compound (B-3-1) represented by the following formula (11a), a compound (B-3-2) represented by the following formula (11b), and a compound having a group represented by the following formula (12) and having a molecular weight of 300 or more and less than 800 or a compound (B-3-3) having a weight average molecular weight of 300 or more and less than 800, In formulas (11a), (11b) and (12), R 31 represents a single bond, an alkylene group having 1 to 4 carbon atoms, or an alkenylene group having 2 to 4 carbon atoms, k represents an integer of 0 or 1, m represents an integer of 1 to 3, n represents an integer of 2 to 4, * represents a bonding site.

8. The composition for forming a protective film according to claim 1, wherein the compound (B-4) having two or more non-phenolic hydroxyl groups is a compound represented by the following formula (B-4-1), In the formula (B-4-1), X represents -O- or -NR-, and in -NR-, R represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms which may have a hydroxyl group, an aryl group having 6 to 12 carbon atoms which may have a substituent, or an aralkyl group having 7 to 13 carbon atoms which may have a substituent, n represents an integer of 1 to 3, and when n is 2 or 3, X may be the same or different.

9. A protective film resistant to a wet etching solution for semiconductors, which is a fired product of a coating film formed from the composition for forming a protective film according to any one of claims 1 to 8.

10. A method for manufacturing a substrate with a protective film used in the manufacture of a semiconductor, which includes the following steps: A step of coating the composition for forming a protective film according to any one of claims 1 to 8 on a semiconductor substrate having a height difference and firing to form a protective film.

11. A method for manufacturing a substrate with a resist pattern used in the manufacture of a semiconductor, which includes the following steps: A step of coating the composition for forming a protective film according to any one of claims 1 to 8 on a semiconductor substrate and firing to form a protective film as an underlayer film for a resist, and A step of forming a resist film directly on or via another layer on the protective film, and then performing exposure and development to form a resist pattern.

12. A method for manufacturing a semiconductor device, which includes the following steps: On a semiconductor substrate having an inorganic film formed on its surface, a protective film is formed using the composition for forming a protective film according to any one of claims 1 to 8. A resist pattern is formed directly on or via another layer on the protective film. The inorganic film surface is exposed by dry-etching the protective film using the resist pattern as a mask. The inorganic film is wet-etched using a wet etching solution for semiconductors with the dry-etched protective film as a mask.

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