Composition for forming resist underlayer film

Abstract

Provided is a composition for forming a resist underlayer film that can form a protective film having excellent resistance to semiconductor wet etching solutions, and that satisfies all of good coating properties, rapid film-curing properties, and good storage stability.　The composition for forming a resist underlayer film includes: (A) a compound or a polymer having a reactive group of a cyclic ether structure represented by formula (I); (B) a compound or polymer having a reactive group that is reactive with the reactive group in (A); (C) an ionic curing catalyst represented by formula (II-1), formula (II-2), or the formula (II-3); and (D) a solvent.

Description

Composition for forming a resist underlayer film

[0001] The present invention relates to a resist underlayer film formation composition for forming a protective film with particularly excellent resistance to semiconductor wet etching solutions in a lithography process in semiconductor manufacturing. The invention also relates to a method for manufacturing a resist-patterned substrate and a semiconductor device using the resist underlayer film formation composition.

[0002] In semiconductor manufacturing, the lithography process, which involves forming a resist underlayer film between a substrate and a resist film formed on it to create a resist pattern of a desired shape, is widely known. After forming the resist pattern, the substrate is processed, and dry etching is mainly used for this process, although wet etching may be used depending on the type of substrate. Patent Document 1 discloses a resist underlayer film material that has resistance to alkaline hydrogen peroxide solution.

[0003] The resist underlayer film used for circuit formation in semiconductor devices is generally used as a cured film after a coating process on various substrates, including silicon, and a firing process to cure the composition. In this process, only a limited number of compositions can produce a chemical reaction that satisfies the requirements of good coatability, rapid film curing, and storage stability.

[0004] Compositions containing epoxy groups are promising because they harden quickly during the firing process and are resistant to semiconductor wet etching solutions. However, compositions in which epoxy groups, reactive groups that react with them, and basic curing agents are diluted with various solvents commonly used in the semiconductor industry are susceptible to deterioration in storage stability due to the reactivity of the basic curing agent.

[0005] Japanese Patent Publication No. 2018-173520

[0006] Liquid compositions used in semiconductor circuit formation, which require coating and firing processes, are required by industrial demands to have excellent coating properties after spin coating in semiconductor processes, film hardening properties, high resistance to wet etching solutions, and storage stability (unchanged molecular weight distribution during long-term storage).

[0007] Therefore, the present invention aims to provide a resist underlayer film formation composition used for circuit formation in semiconductor devices, etc., that satisfies all of the following requirements: good coatability, good resistance to semiconductor wet etching solutions, good storage stability, and film curing in a short time.

[0008] As a result of diligent research to solve the above problems, the present inventors have found that by using a specific ionic curing catalyst with a polymer having a highly reactive cyclic ether structure of a three-membered or four-membered ring and a crosslinking agent having a functional group that reacts with the polymer, a composition can be formed that satisfies the requirements of the semiconductor manufacturing industry, including high storage stability and resistance to semiconductor wet etching solutions, thus completing the present invention.

[0009] In other words, the present invention encompasses the following aspects: [1] A composition for forming a resist underlayer film, comprising: (A) a compound or polymer having a reactive group represented by a cyclic ether structure shown by the following formula (I); (B) a compound or polymer having a reactive group that is reactive with respect to the reactive group in (A); (C) an ionic curing catalyst represented by the following formula (II-1), the following formula (II-2), or the following formula (II-3); and (D) a solvent. (In formula (I), * indicates a bonding site. n represents 1 or 2. When n=1, X represents an ether bond, ester bond, or amide bond; when n=2, X represents a nitrogen atom or an amide bond.) (In formulas (II-1) to (II-3), X － is an anion that does not have a sulfonic acid structure or a sulfonylimide structure. t is 0 or 1. When t is 0, Y ＋ The Y inside is a sulfur atom, and when t is 1, Y ＋ The Y in the middle is either a nitrogen atom or a phosphorus atom. １ ~R ７represents, independently of each other, a hydrogen atom, an alkoxy group having 1 to 10 carbon atoms, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 40 carbon atoms, an organic group containing an ether bond, an organic group containing a ketone bond, an organic group containing an ester bond, or a group combining them. Further, R １ and R ２ and R ３ and R ４ any two of them may be bonded to each other to form a ring together with a sulfur, nitrogen or phosphorus atom in the formula, provided that the case where only R ７ is hydrogen is excluded. In addition, when t is 0, all of R １ to R ３ will not all be hydrogen, and when t is 1, all of R １ to R ４ will not all be hydrogen. R ８ is independently a non-hydrogen substituted body, and n is 1 to 5. ) [2] The resist lower layer film forming composition according to [1], wherein the polymer of (A) is a polymer having a unit structure represented by the following formula (1-1). (In formula (1-1), Ar represents a benzene ring, a naphthalene ring or an anthracene ring, and R １ represents a hydroxy group, a mercapto group optionally protected by a methyl group, an amino group optionally protected by a methyl group, a halogeno group, or an alkyl group having 1 to 10 carbon atoms optionally substituted or interrupted by a hetero atom and optionally substituted by a hydroxy group, n1 represents an integer of 0 to 3, L １ represents a single bond or an alkylene group having 1 to 10 carbon atoms, n2 represents 1 or 2, E represents a group having an epoxy group, or a group having an oxetanyl group, T １ represents an alkylene group having 1 to 10 carbon atoms optionally interrupted by an ether bond, an ester bond or an amide bond when n2 = 1, and T １ represents a trivalent hydrocarbon group having 1 to 10 carbon atoms optionally interrupted by a nitrogen atom or an amide bond when n² = 2. ) [3] The resist lower layer film forming composition according to [1], wherein the polymer of (A) is a polymer having a unit structure represented by the following formula (1-3). (In formula (1-3), R１００ represents a hydrogen atom or a methyl group, n2 represents 1 or 2, E represents a group having an epoxy group or a group having an oxetanyl group, T ２ When n² = 1, it represents an alkylene group having 1 to 10 carbon atoms, which may be interrupted by an ether bond, an ester bond, or an amide bond. ２ When n² = 2, it represents a trivalent hydrocarbon group having 1 to 10 carbon atoms, which may be interrupted by a nitrogen atom or an amide bond.) [4] The resist underlayer film forming composition according to any one of [1] to [3], wherein the polymer of (B) is a polymer having a unit structure represented by the following formula (3-1). (In formula (3-1), T ４ R represents an alkyl group having 1 to 10 carbon atoms, which may be substituted with a hydrogen atom or a halogen group. ４) represents a halogen group, a carboxyl group, a nitro group, a cyano group, a methylenedioxy group, an acetoxy group, a methylthio group, an alkoxy group having 1 to 9 carbon atoms, an amino group which may be substituted with an alkyl group having 1 to 3 carbon atoms, or an alkyl group having 1 to 10 carbon atoms which may be substituted with a hydroxyl group or a halogen group. r4 represents an integer from 0 to 3. n7 represents an integer from 0 to 2. a represents an integer from 1 to 6.) [5] The resist underlayer film forming composition according to any one of [1] to [3], wherein the compound of (B) is a compound containing a thiol structure. [6] The resist underlayer film forming composition according to [1], wherein the compound of (C) is an ionic curing catalyst represented by formula (II-1) or formula (II-2). [7] The resist underlayer film forming composition according to any one of [1] to [6], wherein the solvent of (D) comprises at least one solvent selected from the group consisting of propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, isopropyl alcohol, ethyl acetate, butyl acetate, and cyclohexanone. [8] A resist underlayer film characterized by being a fired product of a coating film made from the resist underlayer film forming composition according to any one of [1] to [7]. [9] A method for manufacturing a resist patterned substrate for use in semiconductor manufacturing, comprising the steps of: applying the resist underlayer film forming composition according to any one of [1] to [7] onto a semiconductor substrate and firing it to form a resist underlayer film; and forming a resist film directly on the resist underlayer film or via another layer, and then exposing and developing it to form a resist pattern.

[10] A method for manufacturing a semiconductor device, comprising the steps of forming a resist underlayer film on a semiconductor substrate on which an inorganic film may be formed on the surface using a resist underlayer film forming composition according to any one of [1] to [7], forming a resist pattern directly or via another layer on the resist underlayer film, dry etching the resist underlayer film using the resist pattern as a mask to expose the surface of the inorganic film or the semiconductor substrate, and wet etching or cleaning the inorganic film or the semiconductor substrate using a semiconductor wet etching solution using the resist underlayer film after dry etching as a mask.

[0010] The present invention provides a resist underlayer film forming composition that can form a protective film with excellent resistance to semiconductor wet etching solutions, and that satisfies all of the following requirements: good applicability, rapid film curing, and good storage stability.

[0011] The present invention will be described in detail below. The following description of the constituent elements is illustrative for illustrating the present invention, and the present invention is not limited to these elements.

[0012] (Composition for forming a resist underlayer film) The resist underlayer film composition of the present invention comprises: (A) a compound or polymer having a reactive group represented by a cyclic ether structure shown by the following formula (I); (B) a compound or polymer having a reactive group that is reactive with the reactive group in (A); (C) an ionic curing catalyst represented by the following formula (II-1), the following formula (II-2), or the following formula (II-3); and (D) a solvent.

[0013] (In formula (I), * indicates a bonding site. n represents 1 or 2. When n=1, X represents an ether bond, ester bond, or amide bond; when n=2, X represents a nitrogen atom or an amide bond.)

[0014] (In formulas (II-1) to (II-3), X － is an anion that does not have a sulfonic acid structure or a sulfonylimide structure. t is 0 or 1. When t is 0, Y ＋ The Y inside is a sulfur atom, and when t is 1, Y ＋ The Y in the middle is either a nitrogen atom or a phosphorus atom. １ ~R ７ Each of these independently represents a hydrogen atom, an alkoxy group having 1 to 10 carbon atoms, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 40 carbon atoms, an organic group containing an ether bond, an organic group containing a ketone bond, an organic group containing an ester bond, or a group combining these. Also, R １ , R ２ , R ３ and R ４Any two of these may bond with each other to form a ring together with the sulfur, nitrogen, or phosphorus atom in the formula, however R ７ Except when only hydrogen is present. Furthermore, if t is 0, R １ ~R ３ Not all of them become hydrogen, and when t is 1, R １ ~R ４ Not all of it will become hydrogen. ８ (These are independently non-hydrogen-substituted compounds, and n is between 1 and 5.)

[0015] The present inventors have found that a resist underlayer film forming composition comprising (A) a compound or polymer having a cyclic ether structure represented by formula (I) above, (B) a compound or polymer having a reactive group that is reactive to the reactive group in (A), (C) an ionic curing catalyst represented by formula (II-1), formula (II-2), or formula (II-3) above, and (D) a solvent satisfies all of the following requirements: good coatability, good resistance to semiconductor wet etching solutions, good storage stability, and rapid film curing. This resist underlayer film forming composition can be suitably used to form a protective film with excellent resistance to semiconductor wet etching solutions, or to form a resist underlayer film in a lithography process (particularly a resist underlayer film with anti-reflective properties).

[0016] <(A) Compound or Polymer> The (A) compound or polymer used in the present invention has a reactive group represented by a cyclic ether structure (epoxy structure or oxetane structure) represented by the above formula (I). More preferred embodiments of the (A) compound or polymer include the polymer shown in the first embodiment below, or the compound shown in the second embodiment.

[0017] <<First Embodiment>> Examples of polymers used in the present invention include the following polymers. Examples of such polymers (hereinafter also referred to as the polymer in the first embodiment) include polymers having a novolac structure with a unit structure represented by the following formula (1-1), and acrylic polymers having a unit structure represented by the following formula (1-3).

[0018] As a polymer in the first embodiment, for example, a polymer having a novolac structure is represented by the following formula (1-1): (In formula (1-1), Ar represents a benzene ring, a naphthalene ring, or an anthracene ring, R １ n1 represents a hydroxyl group, a mercapto group which may be protected by a methyl group, an amino group which may be protected by a methyl group, a halogeno group, or an alkyl group having 1 to 10 carbon atoms which may be substituted or interrupted by a heteroatom or substituted by a hydroxyl group, n1 represents an integer from 0 to 3, L １ represents a single bond or an alkylene group having 1 to 10 carbon atoms, n2 represents 1 or 2, E represents a group having an epoxy group or an oxetanyl group, T １ When n² = 1, it represents an alkylene group having 1 to 10 carbon atoms, which may be interrupted by an ether bond, an ester bond, or an amide bond. １ (When n² = 2, it represents a trivalent hydrocarbon group having 1 to 10 carbon atoms, which may be interrupted by a nitrogen atom or an amide bond.)

[0019] Examples of alkyl groups having 1 to 10 carbon atoms include methyl group, ethyl group, n-propyl group, i-propyl group, cyclopropyl group, n-butyl group, i-butyl group, s-butyl group, t-butyl group, cyclobutyl group, 1-methyl-cyclopropyl group, 2-methyl-cyclopropyl group, n-pentyl group, 1-methyl-n-butyl group, 2-methyl-n-butyl group, 3-methyl-n-butyl group, 1,1-dimethyl-n-propyl group, 1,2-dimethyl-n-propyl group, 2,2-dimethyl-n-propyl group, 1-ethyl-n-propyl group, Cyclopentyl group, 1-methyl-cyclobutyl group, 2-methyl-cyclobutyl group, 3-methyl-cyclobutyl group, 1,2-dimethyl-cyclopropyl group, 2,3-dimethyl-cyclopropyl group, 1-ethyl-cyclopropyl group, 2-ethyl-cyclopropyl group, n-hexyl group, 1-methyl-n-pentyl group, 2-methyl-n-pentyl group, 3-methyl-n-pentyl group, 4-methyl-n-pentyl group, 1,1-dimethyl-n-butyl group, 1,2-dimethyl-n-butyl group, 1,3-dimethyl-n-butyl group, 2,2- Dimethyl-n-butyl group, 2,3-dimethyl-n-butyl group, 3,3-dimethyl-n-butyl group, 1-ethyl-n-butyl group, 2-ethyl-n-butyl group, 1,1,2-trimethyl-n-propyl group, 1,2,2-trimethyl-n-propyl group, 1-ethyl-1-methyl-n-propyl group, 1-ethyl-2-methyl-n-propyl group, cyclohexyl group, 1-methyl-cyclopentyl group, 2-methyl-cyclopentyl group, 3-methyl-cyclopentyl group, 1-ethyl-cyclobutyl group, 2-ethyl-cyclobutyl group, 3 -Ethyl-cyclobutyl group, 1,2-dimethyl-cyclobutyl group, 1,3-dimethyl-cyclobutyl group, 2,2-dimethyl-cyclobutyl group, 2,3-dimethyl-cyclobutyl group, 2,4-dimethyl-cyclobutyl group, 3,3-dimethyl-cyclobutyl group, 1-n-propyl-cyclopropyl group, 2-n-propyl-cyclopropyl group, 1-i-propyl-cyclopropyl group, 2-i-propyl-cyclopropyl group, 1,2,2-trimethyl-cyclopropyl group, 1,2,3-trimethyl-cyclopropyl group, 2,2,Examples include 3-trimethylcyclopropyl group, 1-ethyl-2-methylcyclopropyl group, 2-ethyl-1-methylcyclopropyl group, 2-ethyl-2-methylcyclopropyl group, 2-ethyl-3-methylcyclopropyl group, decyl group, methoxy group, ethoxy group, methoxymethyl group, ethoxymethyl group, methoxyethyl group, ethoxyethyl group, hydroxymethyl group, 1-hydroxyethyl group, 2-hydroxyethyl group, methylamino group, dimethylamino group, diethylamino group, aminomethyl group, 1-aminoethyl group, 2-aminoethyl group, methylthio group, ethylthio group, mercaptomethyl group, 1-mercaptoethyl group, 2-mercaptoethyl group, etc.

[0020] Alkylene groups having 1 to 10 carbon atoms include methylene, ethylene, n-propylene, isopropylene, cyclopropylene, n-butylene, isobutylene, s-butylene, t-butylene, cyclobutylene, 1-methylcyclopropylene, 2-methylcyclopropylene, n-pentylene, 1-methyl-n-butylene, 2-methyl-n-butylene, 3-methyl-n-butylene, 1,1-dimethyl-n-propylene, 1,2-dimethyl-n-propylene, 2,2-dimethyl-n-propylene, and 1-ethyl-n-propylene. Len 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, 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-cyclobutylene 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, 2,2,Examples include 3-trimethylcyclopropylene group, 1-ethyl-2-methylcyclopropylene group, 2-ethyl-1-methylcyclopropylene group, 2-ethyl-2-methylcyclopropylene group, 2-ethyl-3-methylcyclopropylene group, n-heptylene group, n-octylene group, n-nonylene group, or n-decanylene group.

[0021] R １ An example of an alkyl group having 1 to 10 carbon atoms that is substituted or interrupted by a heteroatom is an alkoxy group having 1 to 10 carbon atoms.

[0022] Examples of alkoxy groups having 1 to 10 carbon atoms include methoxy, ethoxy, n-propoxy, i-propoxy, n-butoxy, i-butoxy, s-butoxy, t-butoxy, n-pentoxy, 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, and 4-methyl-n-pentyloxy. Examples include ethyl-n-pentyloxy group, 1,1-dimethyl-n-butoxy group, 1,2-dimethyl-n-butoxy group, 1,3-dimethyl-n-butoxy group, 2,2-dimethyl-n-butoxy group, 2,3-dimethyl-n-butoxy group, 3,3-dimethyl-n-butoxy group, 1-ethyl-n-butoxy group, 2-ethyl-n-butoxy group, 1,1,2-trimethyl-n-propoxy group, 1,2,2-trimethyl-n-propoxy group, 1-ethyl-1-methyl-n-propoxy group, 1-ethyl-2-methyl-n-propoxy group, n-heptyloxy group, n-octyloxy group, and n-nonyloxy group.

[0023] The unit structure represented by formula (1-1) may be one type or a combination of two or more types. For example, it may be a copolymer having multiple unit structures in which Ar is of the same type, and copolymers having multiple unit structures in which Ar is of different types, such as having a unit structure containing a benzene ring and a unit structure containing a naphthalene ring, are not excluded from the scope of the present invention.

[0024] The phrase "may be interrupted" above means that, in the case of alkylene groups having 2 to 10 carbon atoms, any carbon-carbon bond in the alkylene group is interrupted by a heteroatom (i.e., an ether bond in the case of oxygen, a sulfide bond in the case of sulfur), an ester bond, or an amide bond; and in the case of a methylene group having 1 carbon atom, it means that one of the carbon atoms of the methylene group has a heteroatom (i.e., an ether bond in the case of oxygen, a sulfide bond in the case of sulfur), an ester bond, or an amide bond.

[0025] T １ This represents a hydrocarbon group having 1 to 10 carbon atoms (including alkylene groups and trivalent hydrocarbon groups) which may be interrupted by an ether bond, ester bond, nitrogen atom, or amide bond, but the combination of an ether bond and a methylene group (i.e., "-T" in formula (1-1)) １ When "-(E)n2" is a glycidyl ether group, it is preferable that it is a combination of an ester bond and a methylene group, or a combination of an amide bond and a methylene group.

[0026] A C1-C10 alkyl group that may be substituted with a heteroatom means that one or more hydrogen atoms of the C1-C10 alkyl group are substituted with a heteroatom (preferably a halogen group).

[0027] L １ The symbol represents a single bond or an alkylene group having 1 to 10 carbon atoms, as shown in formula (1-2): (In formula (1-2), R ２ , R ３ These independently represent a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an i-propyl group, a cyclopropyl group, an n-butyl group, an i-butyl group, an s-butyl group, a t-butyl group, and a cyclobutyl group, R２ , R ３ It is preferable that these be represented as R (which may be bonded to each other to form a ring with 3 to 6 carbon atoms). ２ , R ３ Both are hydrogen atoms (i.e., -(CR ２ R ３ It is preferable that the group is a methylene group.

[0028] A halogen group refers to a halogen-X (F, Cl, Br, I) that has been substituted with hydrogen.

[0029] In formula (1-1), E is more preferably a group having an epoxy group.

[0030] The polymer having a novolac structure in the first embodiment is not particularly limited, for example, as long as it satisfies the unit structure of formula (1-1). It may be manufactured by a method known to the present day. Commercial products may also be used. Examples of commercial products include the heat-resistant epoxy novolac resin EOCN® series (manufactured by Nippon Kayaku Co., Ltd.) and the epoxy novolac resin D.E.N® series (manufactured by Dow Chemical Japan Ltd.).

[0031] The weight-average molecular weight of the polymer having a novolac structure in the first embodiment is 100 or more, 500 to 200,000, 600 to 50,000, or 700 to 10,000.

[0032] Examples of polymers having a novolac structure in the first embodiment include those having the following unit structures. Me represents a methyl group, and Et represents an ethyl group.

[0033] As a polymer in the first embodiment, for example, an acrylic polymer is represented by the following formula (1-3): (In formula (1-3), R １００ represents a hydrogen atom or a methyl group, n2 represents 1 or 2, E represents a group having an epoxy group or a group having an oxetanyl group, T ２ When n² = 1, it represents an alkylene group having 1 to 10 carbon atoms, which may be interrupted by an ether bond, an ester bond, or an amide bond. ２(When n² = 2, it represents a trivalent hydrocarbon group having 1 to 10 carbon atoms, which may be interrupted by a nitrogen atom or an amide bond.)

[0034] The weight-average molecular weight of the acrylic polymer in the first embodiment is 100 to 20,000, 300 to 10,000, or 500 to 5,000.

[0035] Examples of acrylic polymers in the first embodiment include those having the following unit structure.

[0036] <<Second Embodiment>> Examples of compounds (A) used in the present invention include the following compounds. The compound (hereinafter also referred to as the compound in the second embodiment) is a compound that does not have repeating structural units, and comprises a terminal group (A1), a polyvalent group (A2), and a linking group (A3), wherein the terminal group (A1) is bonded only to the linking group (A3), the polyvalent group (A2) is bonded only to the linking group (A3), the linking group (A3) is bonded to the terminal group (A1) on one side and to the polyvalent group (A2) on the other side, and may optionally be bonded to another linking group (A3), and the terminal group (A1) has any of the structures of the following formula (I), (In formula (I), * indicates the bonding site with the linking group (A3). n represents 1 or 2. When n=1, X represents an ether bond, an ester bond, or an amide bond, and when n=2, X represents a nitrogen atom or an amide bond.) The polyvalent group (A2) is a 2- to 4-valent group selected from the group consisting of -O-, an aliphatic hydrocarbon group, a combination of an aromatic hydrocarbon group having less than 10 carbon atoms and an aliphatic hydrocarbon group, and a combination of an aromatic hydrocarbon group having 10 or more carbon atoms and -O-, and the linking group (A3) represents an aromatic hydrocarbon group, and the compound is such that

[0037] "Having no repeating structural units" means excluding so-called polymers that have repeating structural units, such as polyolefins, polyesters, polyamides, and poly(meth)acrylates. Preferably, the weight-average molecular weight of compound (A) is 300 or more and 1,500 or less.

[0038] The "bonds" between the terminal group (A1), the polyvalent group (A2), and the linking group (A3) refer to chemical bonds, and usually mean covalent bonds, but this does not prevent them from being ionic bonds.

[0039] A polyvalent group (A2) is a group with 2 to 4 valents.

[0040] Therefore, in the definition of a polyvalent group (A2), an aliphatic hydrocarbon group is a divalent to tetravalent aliphatic hydrocarbon group. As a non-restrictive example, divalent aliphatic hydrocarbon groups include methylene group, ethylene group, n-propylene group, isopropylene group, cyclopropylene group, n-butylene group, isobutylene group, s-butylene group, t-butylene group, cyclobutylene group, 1-methyl-cyclopropylene group, 2-methyl-cyclopropylene group, n-pentylene group, 1-methyl-n-butylene group, 2-methyl-n-butylene group, 3-methyl-n-butylene group, 1,1-dimethyl-n-propylene group, and 1,2-dimethyl-n-butylene group. Methyl-n-propylene group, 2,2-dimethyl-n-propylene, 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, 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-cyclobutylene 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,Examples of alkylene groups include 3-dimethylcyclobutylene group, 1-n-propylcyclopropylene group, 2-n-propylcyclopropylene group, 1-isopropylcyclopropylene group, 2-isopropylcyclopropylene group, 1,2,2-trimethylcyclopropylene group, 1,2,3-trimethylcyclopropylene group, 2,2,3-trimethylcyclopropylene group, 1-ethyl-2-methylcyclopropylene group, 2-ethyl-1-methylcyclopropylene group, 2-ethyl-2-methylcyclopropylene group, 2-ethyl-3-methylcyclopropylene group, n-heptylene group, n-octylene group, n-nonylene group, or n-decanylene group.

[0041] By removing hydrogen atoms from any site on these groups and converting them into bonding sites, trivalent and tetravalent groups are derived.

[0042] Examples of aromatic hydrocarbon groups with fewer than 10 carbon atoms in the definition of a polyvalent group (A2) include benzene, toluene, xylene, mesitylene, cumene, styrene, and indene.

[0043] Aliphatic hydrocarbon groups that can be combined with aromatic hydrocarbon groups having fewer than 10 carbon atoms include, in addition to the alkylene group mentioned above, methyl group, ethyl group, n-propyl group, i-propyl group, cyclopropyl group, n-butyl group, i-butyl group, s-butyl group, t-butyl group, cyclobutyl group, 1-methyl-cyclopropyl group, 2-methyl-cyclopropyl group, n-pentyl group, 1-methyl-n-butyl group, 2-methyl-n-butyl group, 3-methyl-n-butyl group, 1,1-dimethyl-n-propyl group, 1,2-dimethyl-n-propyl group, and 2,2-dimethyl -n-propyl group, 1-ethyl-n-propyl group, cyclopentyl group, 1-methyl-cyclobutyl group, 2-methyl-cyclobutyl group, 3-methyl-cyclobutyl group, 1,2-dimethyl-cyclopropyl group, 2,3-dimethyl-cyclopropyl group, 1-ethyl-cyclopropyl group, 2-ethyl-cyclopropyl group, n-hexyl group, 1-methyl-n-pentyl group, 2-methyl-n-pentyl group, 3-methyl-n-pentyl group, 4-methyl-n-pentyl group, 1,1-dimethyl-n-butyl group, 1,2-dimethyl-n-butyl group, 1,3-di Methyl-n-butyl group, 2,2-dimethyl-n-butyl group, 2,3-dimethyl-n-butyl group, 3,3-dimethyl-n-butyl group, 1-ethyl-n-butyl group, 2-ethyl-n-butyl group, 1,1,2-trimethyl-n-propyl group, 1,2,2-trimethyl-n-propyl group, 1-ethyl-1-methyl-n-propyl group, 1-ethyl-2-methyl-n-propyl group, cyclohexyl group, 1-methyl-cyclopentyl group, 2-methyl-cyclopentyl group, 3-methyl-cyclopentyl group, 1-ethyl-cyclobutyl group, 2-ethyl-cyclopentyl group Crobutyl group, 3-ethyl-cyclobutyl group, 1,2-dimethyl-cyclobutyl group, 1,3-dimethyl-cyclobutyl group, 2,2-dimethyl-cyclobutyl group, 2,3-dimethyl-cyclobutyl group, 2,4-dimethyl-cyclobutyl group, 3,3-dimethyl-cyclobutyl group, 1-n-propyl-cyclopropyl group, 2-n-propyl-cyclopropyl group, 1-i-propyl-cyclopropyl group, 2-i-propyl-cyclopropyl group, 1,2,2-trimethyl-cyclopropyl group, 1,2,3-trimethyl-cyclopropyl group, 2,2Examples of alkyl groups include 3-trimethylcyclopropyl group, 1-ethyl-2-methylcyclopropyl group, 2-ethyl-1-methylcyclopropyl group, 2-ethyl-2-methylcyclopropyl group, 2-ethyl-3-methylcyclopropyl group, and decyl group.

[0044] In the definition of a polyvalent group (A2), either an aromatic hydrocarbon group or an aliphatic hydrocarbon group with fewer than 10 carbon atoms may be bonded to a linking group (A3).

[0045] Examples of aromatic hydrocarbon groups with 10 or more carbon atoms in the definition of a polyvalent group (A2) include naphthalene, azulene, anthracene, phenanthrene, naphthacene, triphenylene, pyrene, and chrysene.

[0046] In the definition of a polyvalent group (A2), it is preferable that an aromatic hydrocarbon group having 10 or more carbon atoms is bonded to a linking group (A3) via an -O- linkage.

[0047] Examples of aromatic hydrocarbon groups in the definition of a linking group (A3) include aromatic hydrocarbon groups having fewer than 10 carbon atoms and aromatic hydrocarbon groups having 10 or more carbon atoms.

[0048] Preferably, compound (A) has two or more linking groups (A3).

[0049] The compound in the second embodiment is preferably represented by, for example, the following formula (II). (In formula (II), Z １ , and Z ２ Each is independent (In equation (I), * represents Y) １ , or Y ２ This indicates the bonding site. n represents 1 or 2. When n=1, X represents an ether bond, ester bond, or amide bond, and when n=2, X represents a nitrogen atom or an amide bond. １ , and Y ２ Each of these independently represents an aromatic hydrocarbon group, X １ , and X ２ Each is independently -Y １ -Z １ or -Y ２ -Z２ This represents n1 and n2, each independently representing an integer from 0 to 4, where at least one is 1 or greater, (X １ )m1 defined by m1 represents 0 or 1, (X ２ )m² represents 0 or 1, and Q represents a (n1 + n2) valency group selected from the group consisting of -O-, an aliphatic hydrocarbon group, a combination of an aromatic hydrocarbon group having less than 10 carbon atoms and an aliphatic hydrocarbon group, and a combination of an aromatic hydrocarbon group having 10 or more carbon atoms and -O-. ) Q is preferably a 2- to 4-valency group.

[0050] In equation (II), Z １ , and Z ２ Q is attached to the terminal group (A1), Q is attached to the polyvalent group (A2), and Y １ , and Y ２ These correspond to the above-mentioned linking groups (A3), and their explanations and examples are as described above.

[0051] The compound in the second embodiment preferably includes, for example, a substructure represented by the following formula (III). (In formula (III), Ar represents a benzene ring, a naphthalene ring, or anthracene ring. n represents 1 or 2. When n=1, X represents an ether bond, an ester bond, or an amide bond; when n=2, X represents a nitrogen atom or an amide bond.)

[0052] Examples of compounds in the second embodiment include the following compounds.

[0053] <(B) Compounds or polymers having reactive groups that are reactive to the reactive groups in (A) above> The (B) compound or polymer used in the present invention has a reactive group that is reactive to the reactive groups in (A) above. More preferred embodiments of the (B) compound or polymer include compounds or polymers having a phenolic hydroxyl group as shown in the third aspect below, or compounds having a thiol structure as shown in the fourth aspect.

[0054] <<Third Embodiment>> Examples of compounds or polymers (B) used in the present invention include the following compounds or polymers having a phenolic hydroxyl group. Compounds or polymers having a phenolic hydroxyl group (B) are not particularly limited as long as they do not impair the effects of the present invention. Needless to say, the compounds or polymers having a phenolic hydroxyl group (B) are different from the compounds or polymers (A) described above.

[0055] (B) The weight-average molecular weight of the compound or polymer having a phenolic hydroxyl group (hereinafter also referred to as (B) compound or polymer) is not particularly limited, but is for example 300 to 50,000.

[0056] (B) The compound or polymer preferably has two or more phenolic hydroxyl groups. (B) More preferred embodiments of the compound or polymer include, for example, the compounds or polymers shown in the embodiments of 3-1 to 3-3 below.

[0057] <<Aspect 3-1>> Examples of the (B) compound or polymer used in the present invention include the compound or polymer represented by formula (2-1).

[0058] (In the formula, R ２ Each of these independently represents a halogen group, a carboxyl group, a nitro group, a cyano group, a methylenedioxy group, an acetoxy group, a methylthio group, an alkoxy group having 1 to 9 carbon atoms, an amino group which may be substituted with an alkyl group having 1 to 3 carbon atoms, or an alkyl group having 1 to 10 carbon atoms which may be substituted with a hydroxyl group or a halogen group. １ and A ２ Each of these is independently an alkylene group having 1 to 10 carbon atoms, a divalent organic group derived from a bicyclocyclic compound, a biphenylene group, or -C(T ２ ) (T ３ A divalent organic group represented by ) or a combination thereof, T ２represents a halogen group, carboxyl group, nitro group, cyano group, methylenedioxy group, acetoxy group, methylthio group, alkoxy group having 1 to 9 carbon atoms, amino group which may be substituted with an alkyl group having 1 to 3 carbon atoms, or alkyl group having 1 to 10 carbon atoms which may be substituted with a hydroxyl group or a halogen group. ３ represents a hydrogen atom or a monovalent group represented by formula (2-1-a).

[0059] In equation (2-1-a), * represents T ３ R represents the bonding site with the carbon atom to which it is bonded. ２ R in equation (2-1) ２ This is equivalent to the following: a represents an integer from 1 to 6. n3 to n5 each independently represent an integer from 0 to 2. r2 represents an integer from 0 to 3. m1 and m2 each independently represent 0 to 10,000,000.) It is preferable that m1, n3 to n5 and r2 are 0 and m2 is 1.

[0060] The explanations of the halogeno group, alkoxy group, and alkyl group related to formula (2-1) are as described above.

[0061] Examples of bicyclocyclic ring compounds include dicyclopentadiene, substituted dicyclopentadiene, tetracyclo[4.4.0.12,5.17,10]dodeca-3,8-diene, or substituted tetracyclo[4.4.0.12,5.17,10]dodeca-3,8-diene. Substitution means that one or more hydrogen atoms of the bicyclocyclic ring compound are independently substituted with a halogen group, a nitro group, an amino group, or a hydroxyl group, or with an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 40 carbon atoms, which may be substituted with these groups. A divalent organic group derived from a bicyclocyclic ring compound is a group having two bonds that is derived by removing any two hydrogen atoms from a bicyclocyclic ring compound.

[0062] Examples of aryl groups having 6 to 40 carbon atoms include phenyl group, o-methylphenyl group, m-methylphenyl group, p-methylphenyl group, o-chlorophenyl group, m-chlorophenyl group, p-chlorophenyl group, o-fluorophenyl group, p-fluorophenyl group, o-methoxyphenyl group, p-methoxyphenyl group, p-nitrophenyl group, p-cyanophenyl group, α-naphthyl group, β-naphthyl group, o-biphenylyl group, m-biphenylyl group, p-biphenylyl group, 1-anthryl group, 2-anthryl group, 9-anthryl group, 1-phenanthryl group, 2-phenanthryl group, 3-phenanthryl group, 4-phenanthryl group, and 9-phenanthryl group.

[0063] Specific examples of compounds represented by formula (2-1) include the compounds listed below. (B) The compound or polymer may be one of the following compounds:

[0064]

[0065] <<Aspect 3-2>> Examples of the (B) compound or polymer used in the present invention include the compound represented by formula (2-2).

[0066] (In the formula, R ３ This represents a halogen group, carboxyl group, nitro group, cyano group, methylenedioxy group, acetoxy group, methylthio group, alkoxy group having 1 to 9 carbon atoms, an amino group which may be substituted with an alkyl group having 1 to 3 carbon atoms, or an alkyl group having 1 to 10 carbon atoms which may be substituted with a hydroxyl group or a halogen group. Q １ represents a single bond, an oxygen atom, a sulfur atom, a sulfonyl group, a carbonyl group, an imino group, an arylene group having 6 to 40 carbon atoms, or an alkylene group having 1 to 10 carbon atoms, which may be substituted with a halogeno group. a represents an integer from 1 to 6. n6 represents an integer from 0 to 2. r3 represents an integer from 0 to 3. The explanation of the alkoxy group, alkyl group and halogeno group in formula (2-2) is as described above.

[0067] Examples of arylene groups having 6 to 40 carbon atoms include phenylene group, o-methylphenylene group, m-methylphenylene group, p-methylphenylene group, o-chlorphenylene group, m-chlorphenylene group, p-chlorphenylene group, o-fluorophenylene group, p-fluorophenylene group, o-methoxyphenylene group, p-methoxyphenylene group, p-nitrophenylene group, p-cyanophenylene group, α-naphthylene group, β-naphthylene group, o-biphenylylene group, m-biphenylylene group, p-biphenylylene group, 1-antrylene group, 2-antrylene group, 9-antrylene group, 1-phenanthrylene group, 2-phenanthrylene group, 3-phenanthrylene group, 4-phenanthrylene group, and 9-phenanthrylene group.

[0068] Alkylene groups having 1 to 10 carbon atoms include methylene, ethylene, n-propylene, isopropylene, cyclopropylene, n-butylene, isobutylene, s-butylene, t-butylene, cyclobutylene, 1-methylcyclopropylene, 2-methylcyclopropylene, n-pentylene, 1-methyl-n-butylene, 2-methyl-n-butylene, 3-methyl-n-butylene, 1,1-dimethyl-n-propylene, 1,2-dimethyl-n-propylene, 2,2-dimethyl-n-propylene, and 1-ethyl-n-propylene. Len 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, 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-cyclobutylene 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, 2,2,3-trimethyl-cyclopropylene group, 1-ethyl-2-methyl-cyclopropylene group, 2-ethyl-1-methyl-cyclopropylene group, 2-ethyl-2-methyl-cyclopropylene group, 2-ethyl-3-methyl-cyclopropylene group, n-heptylene group, n-octylene group, n-nonylene group or n-decanylene group may be mentioned.

[0069] Specific examples of the compound represented by the formula (2-2) include the compounds described below. The compound (B) may be a compound represented by the following formula (4-1).

[0070] (In the formula, R ５ represents a halogeno group, a carboxy group, a nitro group, a cyano group, a methylenedioxy group, an acetoxy group, a methylthio group, an alkoxy group having 1 to 9 carbon atoms, an amino group optionally substituted with an alkyl group having 1 to 3 carbon atoms, or an alkyl group having 1 to 10 carbon atoms optionally substituted with a hydroxy group or a halogeno group. In the formula, n8 represents an integer of 4, 5, 6, or 8.) The explanations of the above terms are as described above.

[0071] Specific examples of the compound represented by the formula (4-1) are shown below. The compound (B) may be a compound represented by the following formula (5-1) and formula (5-1-a).

[0072] (In the formula, n9 and n10 each represent an integer of 0 or 1, and R ６ represents a halogeno group, a carboxy group, a nitro group, a cyano group, a methylenedioxy group, an acetoxy group, a methylthio group, an alkoxy group having 1 to 9 carbon atoms, an amino group optionally substituted with an alkyl group having 1 to 3 carbon atoms, or an alkyl group having 1 to 10 carbon atoms optionally substituted with a hydroxy group or a halogeno group. a represents an integer of 1 to 6. n11 represents an integer of 1 or 2. r5 represents an integer of 0 to 3. * represents the bonding site between the structure represented by the formula (5-1) and the structure represented by the formula (5-1-a).) The explanations of the above terms are as described above.

[0073] Specific examples of compounds represented by formulas (5-1) and (5-1-a) are shown below. (B) The compound may be one of the following compounds.

[0074]

[0075] <<Aspect 3-3>> The compound (B) or polymer used in the present invention is not particularly limited as long as it is a polymer that does not impair the effects of the present invention. For example, the polymer (B) preferably has at least three or more repeating unit structures.

[0076] (B) The weight-average molecular weight of the polymer is not particularly limited, but is for example between 1,000 and 50,000.

[0077] (B) The polymer preferably contains a unit structure represented by the following formula (3-1). (In the formula, T ４ R represents an alkyl group having 1 to 10 carbon atoms, which may be substituted with a hydrogen atom or a halogen group. ４ represents a halogen group, carboxyl group, nitro group, cyano group, methylenedioxy group, acetoxy group, methylthio group, alkoxy group having 1 to 9 carbon atoms, amino group which may be substituted with an alkyl group having 1 to 3 carbon atoms, or alkyl group having 1 to 10 carbon atoms which may be substituted with a hydroxyl group or a halogen group. r4 represents an integer from 0 to 3. n7 represents an integer from 0 to 2. a represents an integer from 1 to 6. The explanations of halogen groups, alkyl groups and alkoxy groups are as described above.

[0078] The polymer represented by (Equation 3-1) may be a polymer containing one of the unit structures represented by (Equation 3-1), or a copolymer containing two or more of them.

[0079] Specific examples of polymers (B) represented by (Equation 3-1) include polymers containing the unit structures described below. (In the above formula, m and n written next to the repeating unit represent the molar ratio of copolymerization.)

[0080] <<Fourth Embodiment>> Examples of compounds (B) used in the present invention include compounds having a thiol structure. Examples of compounds having a thiol structure according to the present invention include polyfunctional thiol compounds represented by the following formula (10-1).

[0081] (In formula (10-1), R ７ represents a single bond or a linear or branched alkylene group having 1 to 6 carbon atoms, X represents a single bond or ester bond, A represents an organic group or heteroatom having 2 to 12 carbon atoms, r １ (This represents an integer between 2 and 6.)

[0082] A may contain at least one heteroatom, or it may not contain any heteroatoms. Examples of heteroatoms in A include oxygen atoms and nitrogen atoms.

[0083] Examples of compounds containing a thiol structure include 1,2-ethanedithiol, 1,3-propanedithiol, 1,10-decanedithiol, 3,6-dioxaoctane-1,8-dithiol, 2,2'-oxyethanethiol, 2,3-dimercapto-1-propanol, dithioerythritol, dithiothreitol, 1,4-benzenedithiol, 1,3-benzenedithiol, 1,2-benzenedithiol, and 4-chloro-1,3-benzenedithiol. L, 4-methyl-1,2-benzenedithiol, 4,5-dimethyl-1,2-benzenedimethanethiol, 2,3-quinoxylenthiol, 2-dimethylamino-1,3,5-triazine-4,6-dithiol, 2-methoxy-1,3,5-triazine-4,6-dithiol, 2-dibutylamino-1,3,5-triazine-4,6-dithiol, 2-N-phenylamino-1,3,5-triazine-4,6-dithiol, dicyclohexylamino- 1,3,5-Triadine-4,6-Dithiol, Thiocyanuric Acid, Bismuthiol, Bis(2-Mercaptoethyl) Ether, Trimethylolpropane Tris(3-Mercaptopropionate), Tris-[(3-Mercaptopropionyloxy)-ethyl]-Isocyanurate, Tetraethylene Glycol Bis(3-Mercaptopropionate), Dipentaerythritol Hexakis(3-Mercaptopropionate), Pentaerythritol Tetra Examples include tris(3-mercaptobutyrate), 1,4-bis(3-mercaptobutyryloxy)butane, 1,3,5-tris(3-mercaptobutyryloxyethyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, trimethylolpropanetris(3-mercaptobutyrate), trimethylolethanetris(3-mercaptobutyrate), and pentaerythritoltris(3-mercaptopropyl) ether.

[0084] As the polyfunctional thiol compound represented by the above formula (10-1), commercially available products such as Karenz MT (registered trademark) PE1, NR1, BD1, TPMB, TEMB (manufactured by Showa Denko K.K.), and TMMP, TEM PIC, PEMP, EGMP-4, DPM P, TMMP II-20P, PEMP II-20P, PEP T (manufactured by SC Organic Chemistry Co., Ltd.) can be used.

[0085] Examples of the polyfunctional thiol compound represented by the above formula (10-1) include the following compounds.

[0086] In the composition for forming a resist underlayer film of the present invention, the content of the compound or polymer having a reactive group reactive with the reactive group in (A) above, for example, the lower limit of the content is usually 1% by mass, preferably 5% by mass, based on the total solid content of the composition for forming a resist underlayer film, and the upper limit of the content is usually 70% by mass, preferably 50% by mass, more preferably 30% by mass, based on the total solid content of the composition for forming a resist underlayer film.

[0087] <(C) Ionic curing catalyst> The (C) ionic curing catalyst used in the present invention is an onium salt catalyst represented by the following formula (II-1), the following formula (II-2), or the following formula (II-3).

[0088] (In formulas (II-1) to (II-3), X － is an anion having no sulfonic acid structure or sulfonylimide structure. t is 0 or 1. When t is 0, Y ＋ in Y is a sulfur atom, and when t is 1, Y ＋ in Y is a nitrogen atom or a phosphorus atom. R １ to R ７ each independently represents a hydrogen atom, an alkoxy group having 1 to 10 carbon atoms, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 40 carbon atoms, an organic group containing an ether bond, an organic group containing a ketone bond, an organic group containing an ester bond, or a group combining them. Also, R １ R ２ R ３and R ４ Any two of these may bond with each other to form a ring together with the sulfur, nitrogen, or phosphorus atom in the formula, however R ７ Except when only hydrogen is present. Furthermore, if t is 0, R １ ~R ３ Not all of them become hydrogen, and when t is 1, R １ ~R ４ Not all of it will become hydrogen. ８ ( is independently a non-hydrogen-substituted compound, and n is 1 to 5.) Among the compounds of (C) above, it is more preferable that it is an ionic curing catalyst represented by formula (II-1) or formula (II-2) above.

[0089] (C) The ionic curing catalyst is an onium salt catalyst whose cation is a primary to tertiary sulfonium ion, primary to quaternary ammonium ion, primary to quaternary phosphonium ion, imidazole ion, or pyridinium ion, as shown in the above formula. However, those in the above formula that include a sulfonic acid structure or a sulfonylimide structure in the anion are excluded. Here, a sulfonic acid structure is as shown in the following formula (V1), and a sulfonylimide structure is as shown in the following formula (V2).

[0090]

[0091] Specific examples of onium salt catalysts used as ionic curing catalysts in the present invention are shown below. However, the invention is not limited to these examples.

[0092]

[0093]

[0094]

[0095]

[0096] The ionic curing catalyst of the present invention can be, among the above specific examples, an onium salt catalyst made of phosphate, such as the onium salt catalysts shown in formulas (1), (2), and (6); an onium salt catalyst made of trifluoroacetate, such as the onium salt catalyst shown in formula (4); or an onium salt catalyst made of nitrate, such as the onium salt catalyst shown in formula (5). Among these, an onium salt catalyst made of phosphate is more preferred.

[0097] A preferred embodiment of the anion portion in the ionic curing catalyst of the present invention is the anion portion of a phosphate represented by the following formula (W).

[0098] In formula (W), X １ ~X ４ Each of these independently represents either a sulfur atom or an oxygen atom. １０１ ~R １０２ Each of these independently represents an alkyl group having 1 to 10 carbon atoms. Note that, as shown in formula (W) above, X in formula (W) １ ~X ４ The definition includes cases where not only oxygen atoms but also sulfur atoms are present, and in this invention, even cases containing sulfur atoms are referred to as phosphates.

[0099] A preferred embodiment of the ionic curing catalyst of the present invention is, for example, an onium salt catalyst obtained by combining a cation portion of a phosphonium ion and an anion portion of a phosphate salt, as shown in formula (1) above.

[0100] In the resist underlayer film forming composition of the present invention, the content of (C) ionic curing catalyst is, for example, typically 0.001% by mass, preferably 0.005% by mass, and more preferably 0.01% by mass, relative to the total solid content of the resist underlayer film forming composition, and the upper limit of its content is typically 1% by mass, preferably 0.5% by mass, and more preferably 0.05% by mass, relative to the total solid content of the resist underlayer film forming composition.

[0101] <(D) Solvent> The resist underlayer film forming composition of the present invention can be prepared by dissolving each of the above-mentioned components in a solvent, preferably an organic solvent, and is used in a homogeneous solution state.

[0102] The organic solvent used in the resist underlayer film forming composition according to the present invention is not particularly limited, as long as it is an organic solvent capable of dissolving solid components such as the compounds or polymers of (A) to (C) above, or other optionally selected solid components. In particular, since the resist underlayer film forming composition according to the present invention is used in a uniform solution state, it is recommended to use in combination with an organic solvent commonly used in lithography processes, considering its coating performance.

[0103] 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 monoethyl ether, propylene glycol monomethyl ether acetate, propylene glycol propyl ether acetate, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, and cyclamine. Examples of solvents include lopentanone, cyclohexanone, cycloheptanone, 4-methyl-2-pentanol, ethoxyethyl acetate, 2-hydroxyethyl acetate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, isopropyl alcohol, 2-heptanone, methoxycyclopentane, anisole, γ-butyrolactone, N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide. These solvents can be used individually or in combination of two or more.

[0104] Among these solvents, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, isopropyl alcohol, ethyl acetate, butyl acetate, and cyclohexanone are preferred. Propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate are particularly preferred.

[0105] The solid content of the resist underlayer film forming composition 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 percentage of all components in the resist underlayer film forming composition excluding the solvent. The percentage of the above (A) compound or polymer in the solid content is preferably 1 to 100% by mass, more preferably 1 to 99.9% by mass, even more preferably 50 to 99.9% by mass, even more preferably 50 to 95% by mass, and particularly preferably 50 to 90% by mass.

[0106] The resist underlayer film forming composition of the present invention may contain other components used as a resist underlayer film forming composition, within the range that achieves the effects of the present invention.

[0107] (Specific methods of using the resist underlayer film formation composition) The resist underlayer film formation composition of the present invention can be used to form a resist underlayer film in a lithography process (in particular to form a resist underlayer film with anti-reflective properties), or to form a protective film with excellent resistance to semiconductor wet etching solutions.

[0108] (Method for manufacturing a resist underlayer film, a substrate with a resist pattern, and a method for manufacturing a semiconductor device) The resist underlayer film of the present invention is a fired product of a coated film made from the resist underlayer film forming composition of the present invention. The method for manufacturing a substrate with a resist underlayer film according to the present invention includes the step of coating the resist underlayer film forming composition of the present invention onto a semiconductor substrate and firing it to form a resist underlayer film. The method for manufacturing a substrate with a resist underlayer film is used in the manufacture of semiconductors. The method for manufacturing a substrate with a resist pattern according to the present invention includes the step of coating the resist underlayer film forming composition of the present invention onto a semiconductor substrate and firing it to form a resist underlayer film, and the step of forming a resist film directly on the resist underlayer film or via another layer, and then exposing and developing it to form a resist pattern. The method for manufacturing a substrate with a resist pattern is used in the manufacture of semiconductors.

[0109] The method for manufacturing a semiconductor device of the present invention includes the following processes (A) to (D): Process (A): A process to form a resist underlayer film on a semiconductor substrate on which an inorganic film may be formed on the surface, using the resist underlayer film forming composition of the present invention. Process (B): A process to form a resist pattern on the resist underlayer film, either directly or via another layer. Process (C): A process to dry etch the resist underlayer film using the resist pattern as a mask, exposing the surface of the inorganic film or semiconductor substrate. Process (D): A process to wet etch or clean the inorganic film or semiconductor substrate using a semiconductor wet etching solution, using the resist underlayer film after dry etching as a mask.

[0110] Examples of semiconductor substrates to which the resist underlayer film formation composition of the present invention is coated include silicon wafers, germanium wafers, and compound semiconductor wafers such as gallium arsenide, indium phosphide, gallium nitride, indium nitride, and aluminum nitride.

[0111] When using a semiconductor substrate with an inorganic film formed on its surface, the inorganic film is formed by, for example, ALD (atomic layer deposition), CVD (chemical vapor deposition), reactive sputtering, ion plating, vacuum deposition, or spin coating (spin-on-glass: SOG). Examples of the inorganic film include polysilicon films, silicon oxide films, silicon nitride films, silicon oxynitride films, BPSG (Boro-Phosphoric Acid Glass) films, titanium nitride films, titanium oxynitride films, tungsten nitride films, gallium nitride films, and gallium arsenide films. The semiconductor substrate may also be a stepped substrate with so-called vias (holes), trenches (grooves), etc. formed on it. For example, a via has a roughly circular shape when viewed from above, with a diameter of approximately 2 nm to 20 nm and a depth of 50 nm to 500 nm, while a trench has a width of 2 nm to 20 nm and a depth of 50 nm to 500 nm. The resist underlayer film formation composition of the present invention has a small weight-average molecular weight and average particle size of the compounds contained in the composition. Therefore, the composition can be embedded in stepped substrates like the one described above without defects such as voids. The absence of defects such as voids is an important characteristic for subsequent processes in semiconductor manufacturing (wet etching / dry etching of semiconductor substrates, resist pattern formation).

[0112] The resist underlayer film forming composition of the present invention is applied to such a semiconductor substrate by an appropriate coating method such as a spinner or coater. Then, the resist underlayer film is formed by baking using a heating means such as a hot plate. The baking conditions are appropriately selected 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, more preferably, the baking temperature is 150°C to 300°C and the baking time is 0.8 minutes to 10 minutes. The thickness of the formed semiconductor element forming film is, for example, 0.001 μm to 10 μm, preferably 0.002 μm to 1 μm, and more preferably 0.005 μm to 0.5 μm. If the baking temperature is lower than the above range, crosslinking may be insufficient, and the resistance of the formed resist underlayer film to the resist solvent or basic hydrogen peroxide aqueous solution may be difficult to obtain. On the other hand, if the baking temperature is higher than the aforementioned range, the resist underlayer may decompose due to heat.

[0113] A resist film is formed directly or via another layer on the resist underlayer film formed as described above, and then exposed and developed to form a resist pattern. Exposure is performed through a mask (reticle) for forming a predetermined pattern, and for example, i-ray, KrF excimer laser, ArF excimer laser, EUV (extreme ultraviolet), or EB (electron beam) is used. For development, an alkaline developer is used, and the development temperature is appropriately selected from 5°C to 50°C and the development time from 10 seconds to 300 seconds. As the alkaline developer, aqueous solutions of alkalis such as inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia, primary amines such as ethylamine and n-propylamine, secondary amines such as diethylamine and di-n-butylamine, tertiary amines such as triethylamine and methyldiethylamine, alcohol amines 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. Furthermore, appropriate amounts of alcohols such as isopropyl alcohol and nonionic surfactants can be added to the aqueous solutions of the above alkalis. Among these, preferred developers are quaternary ammonium salts, and more preferably tetramethylammonium hydroxide and choline. Furthermore, surfactants can also be added to these developers. Alternatively, development can be performed using an organic solvent such as butyl acetate instead of an alkaline developer, and the parts of the photoresist where the alkali dissolution rate has not improved can be developed.

[0114] Next, the resist underlayer film is dry-etched using the formed resist pattern as a mask. At this time, if the inorganic film is formed on the surface of the semiconductor substrate used, the surface of the inorganic film is exposed; if the inorganic film is not formed on the surface of the semiconductor substrate used, the surface of the semiconductor substrate is exposed.

[0115] Furthermore, the desired pattern is formed by wet etching using a semiconductor wet etching solution, with the resist underlayer film after dry etching (and the resist pattern remaining on that underlayer film, if any) as a mask.

[0116] For semiconductor wet etching solutions, general chemicals used for etching semiconductor wafers can be used, including substances that exhibit both acidic and basic properties.

[0117] Examples of acidic substances include hydrogen peroxide, hydrofluoric acid, ammonium fluoride, acidic ammonium fluoride, ammonium hydrogen fluoride, buffered hydrofluoric acid, hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, or mixtures thereof.

[0118] Examples of substances exhibiting basicity include ammonia, sodium hydroxide, potassium hydroxide, sodium cyanide, potassium cyanide, and basic hydrogen peroxide solution obtained by mixing hydrogen peroxide with organic amines such as triethanolamine to make the pH basic. A specific example is SC-1 (ammonia-hydrogen peroxide solution). In addition, other substances that can make the pH basic, such as a solution obtained by mixing urea with hydrogen peroxide and generating ammonia by thermal decomposition of urea through heating, which ultimately makes the pH basic, can also be used as a chemical solution for wet etching.

[0119] Among these, acidic hydrogen peroxide solution or basic hydrogen peroxide solution is preferred.

[0120] These chemical solutions may contain additives such as surfactants.

[0121] The operating temperature for semiconductor wet etching solutions is preferably 25°C to 90°C, and more preferably 40°C to 80°C. The wet etching time is preferably 0.5 minutes to 30 minutes, and more preferably 1 minute to 20 minutes.

[0122] The contents and effects of the present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0123] The weight-average molecular weights of the compounds synthesized in the following examples of this specification were obtained by gel permeation chromatography (hereinafter abbreviated as GPC). A GPC instrument manufactured by Tosoh Corporation was used for the measurement, and the measurement conditions were as follows.

[0124] GPC column; Column temperature: 40°C; Solvent: Tetrahydrofuran (THF); Flow rate: 0.35 ml / min; Standard sample: Polystyrene (manufactured by Tosoh Corporation)

[0125] <Explanation of Terms> PGME: Propylene glycol monomethyl ether PGMEA: Propylene glycol monomethyl ether acetate

[0126] <Example 1> 0.43 g of epoxy novolac resin EOCN-104S (product of Nippon Kayaku Co., Ltd., corresponding to formula (a-1) below) (weight-average molecular weight: 3100), 0.86 g of 3,7-dihydroxy-2-naphthoate-tri(2,3-epoxypropyl) isocyanurate copolymer (corresponding to formula (2-2-t) below), 0.013 g of tributyl(ethyl)phosphonium diethyl phosphate (product of Tokyo Chemical Industry Co., Ltd., corresponding to formula (c-1) below), 69.09 g of PGMEA, and 29.61 g of PGMEA were mixed to prepare a 1.3% by mass solids solution. This solution was filtered using a polytetrafluoroethylene microfilter with a pore size of 0.2 μm to prepare a composition for forming a resist underlayer film.

[0127]

[0128] <Example 2> 2.86 g of epoxy novolac resin EOCN-104S (product of Nippon Kayaku Co., Ltd., corresponding to formula (a-1) above) (weight-average molecular weight: 3100), 0.72 g of VP-2500 (product of Nippon Soda Co., Ltd., corresponding to formula (b-1) below, weight-average molecular weight: 3687), 0.007 g of tributyl(ethyl)phosphonium diethyl phosphate (product of Tokyo Chemical Industry Co., Ltd., corresponding to formula (c-1) above), 67.49 g of PGMEA, and 28.92 g of PGME were mixed to prepare a 3.6% by mass solids solution. This solution was filtered using a polytetrafluoroethylene microfilter with a pore size of 0.2 μm to prepare a composition for forming a resist underlayer film.

[0129] <Example 3> 2.85 g of epoxy novolac resin EOCN-104S (product of Nippon Kayaku Co., Ltd., corresponding to formula (a-1) above) (weight-average molecular weight: 3100), 0.71 g of Karenz MT® NR1 (product of Resonac Co., Ltd., corresponding to formula (b-3) below), 0.028 g of tributyl(ethyl)phosphonium diethyl phosphate (product of Tokyo Chemical Industry Co., Ltd., corresponding to formula (c-1) above), 67.49 g of PGMEA, and 28.92 g of PGME were mixed to prepare a 3.6% by mass solids solution. The solution was filtered using a polytetrafluoroethylene microfilter with a pore size of 0.2 μm to prepare a composition for forming a resist underlayer film.

[0130] <Example 4> 0.43 g of epoxy novolac resin EOCN-104S (product of Nippon Kayaku Co., Ltd., corresponding to formula (a-1) above) (weight-average molecular weight: 3100), 0.86 g of 3,7-dihydroxy-2-naphthoate-tri(2,3-epoxypropyl) isocyanurate copolymer (corresponding to formula (2-2-t) above), 0.013 g of tributyl(methyl)ammonium dibutyl phosphate (product of Tokyo Chemical Industry Co., Ltd., corresponding to formula (c-2) below), 69.09 g of PGMEA, and 29.61 g of PGMEA were mixed to prepare a 1.3% by mass solids solution. The solution was filtered using a polytetrafluoroethylene microfilter with a pore size of 0.2 μm to prepare a composition for forming a resist underlayer film.

[0131] <Example 5> 0.43 g of epoxy novolac resin EOCN-104S (product of Nippon Kayaku Co., Ltd., corresponding to formula (a-1) above) (weight-average molecular weight: 3100), 0.86 g of 3,7-dihydroxy-2-naphthoate-tri(2,3-epoxypropyl) isocyanurate copolymer (corresponding to formula (2-2-t) above), 0.013 g of 1-ethyl-3-methylimidazolium nitrate (product of Tokyo Chemical Industry Co., Ltd., corresponding to formula (c-3) below), 69.09 g of PGMEA, and 29.61 g of PGMEA were mixed to prepare a 1.3% by mass solids solution. The solution was filtered using a polytetrafluoroethylene microfilter with a pore size of 0.2 μm to prepare a composition for forming a resist underlayer film.

[0132] <Example 6> 0.43 g of epoxy novolac resin EOCN-104S (product of Nippon Kayaku Co., Ltd., corresponding to formula (a-1) above) (weight-average molecular weight: 3100), 0.86 g of 3,7-dihydroxy-2-naphthoate-tri(2,3-epoxypropyl) isocyanurate copolymer (corresponding to formula (2-2-t) above), 0.013 g of 1-ethyl-3-methylimidazolium diethyl phosphate (product of Tokyo Chemical Industry Co., Ltd., corresponding to formula (c-4) below), 69.09 g of PGMEA, and 29.61 g of PGMEA were mixed to prepare a 1.3% by mass solids solution. The solution was filtered using a polytetrafluoroethylene microfilter with a pore size of 0.2 μm to prepare a composition for forming a resist underlayer film.

[0133] <Example 7> 0.43 g of epoxy novolac resin EOCN-104S (product of Nippon Kayaku Co., Ltd., corresponding to formula (a-1) above) (weight-average molecular weight: 3100), 0.86 g of 3,7-dihydroxy-2-naphthoate-tri(2,3-epoxypropyl) isocyanurate copolymer (corresponding to formula (2-2-t) above), 0.013 g of 1-ethyl-3-methylimidazolium trifluoroacetate (product of Tokyo Chemical Industry Co., Ltd., corresponding to formula (c-5) below), 69.09 g of PGMEA, and 29.61 g of PGMEA were mixed to prepare a 1.3% by mass solids solution. The solution was filtered using a polytetrafluoroethylene microfilter with a pore size of 0.2 μm to prepare a composition for forming a resist underlayer film.

[0134] <Comparative Example 1> 0.43 g of epoxy novolac resin EOCN-104S (product of Nippon Kayaku Co., Ltd., corresponding to formula (a-1) above) (weight-average molecular weight: 3100), 0.85 g of 3,7-dihydroxy-2-naphthoate-tri(2,3-epoxypropyl) isocyanurate copolymer (corresponding to formula (2-2-t) above), 0.013 g of TAG-2689 (manufactured by King Industries, quaternary ammonium salt of trifluoromethanesulfonic acid), 69.09 g of PGMEA, and 29.61 g of PGMEA were mixed to prepare a 1.3% by mass solids solution. This solution was filtered using a polytetrafluoroethylene microfilter with a pore size of 0.2 μm to prepare a composition for forming a resist underlayer film.

[0135] <Comparative Example 2> 0.43 g of epoxy novolac resin EOCN-104S (product of Nippon Kayaku Co., Ltd., corresponding to formula (a-1) above) (weight-average molecular weight: 3100), 0.86 g of 3,7-dihydroxy-2-naphthoate-tri(2,3-epoxypropyl) isocyanurate copolymer (corresponding to formula (2-2-t) above), 0.008 g of trifluoromethanesulfonic acid (product of Tokyo Chemical Industry Co., Ltd., corresponding to formula (rc-1) below), 69.09 g of PGMEA, and 29.61 g of PGMEA were mixed to prepare a 1.3% by mass solids solution. This solution was filtered using a polytetrafluoroethylene microfilter with a pore size of 0.2 μm to prepare a composition for forming a resist underlayer film.

[0136] <Comparative Example 3> 0.43 g of epoxy novolac resin EOCN-104S (product of Nippon Kayaku Co., Ltd., corresponding to formula (a-1) above) (weight-average molecular weight: 3100), 0.86 g of 3,7-dihydroxy-2-naphthoate-tri(2,3-epoxypropyl) isocyanurate copolymer (corresponding to formula (2-2-t) above), 0.013 g of 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (product of Tokyo Chemical Industry Co., Ltd., corresponding to formula (rc-2) below), 69.09 g of PGMEA, and 29.61 g of PGMEA were mixed to prepare a 1.3% by mass solids solution. The solution was filtered using a polytetrafluoroethylene microfilter with a pore size of 0.2 μm to prepare a composition for forming a resist underlayer film.

[0137] <Comparative Example 4> 2.86 g of epoxy novolac resin EOCN-104S (product of Nippon Kayaku Co., Ltd., corresponding to formula (a-1) above) (weight-average molecular weight: 3100), 0.72 g of VP-2500 (product of Nippon Soda Co., Ltd., corresponding to formula (b-1) above, weight-average molecular weight: 3687), 0.007 g of 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (product of Tokyo Chemical Industry Co., Ltd., corresponding to formula (rc-2) above), 67.49 g of PGMEA, and 28.92 g of PGME were mixed to prepare a 3.6% by mass solids solution. This solution was filtered using a polytetrafluoroethylene microfilter with a pore size of 0.2 μm to prepare a composition for forming a resist underlayer film.

[0138] <Comparative Example 5> As an example of a general resist underlayer film applicable to ArF lithography, ARC29A-303 (a product of Nissan Chemical Corporation) was used. The resist underlayer film forming composition that forms the resist underlayer film does not satisfy either requirement (A) (a compound or polymer having a reactive group represented by a cyclic ether structure represented by formula (I)) or requirement (C) (an ionic curing catalyst represented by formula (II-1), formula (II-2), or formula (II-3)) as defined in claim 1.

[0139] <Comparative Example 6> As an example of a general resist underlayer film applicable to KrF lithography, DUV42P-306 (a product of Nissan Chemical Corporation) was used. The resist underlayer film forming composition that forms the resist underlayer film does not satisfy either requirement (A) (a compound or polymer having a reactive group represented by a cyclic ether structure represented by formula (I)) or requirement (C) (an ionic curing catalyst represented by formula (II-1), formula (II-2), or formula (II-3)) as defined in claim 1.

[0140] (Resistance Test to Organic Solvents) The resist underlayer film forming compositions prepared in Examples 1 to 7 and Comparative Examples 1 to 6 were applied to silicon substrates and fired at 220°C to produce coating films. The film thickness of the produced coating films was 23 nm for Examples 1, 4 to 7 and Comparative Examples 1 to 3, 100 nm for Examples 2 to 3 and Comparative Example 4, 30 nm for Comparative Example 5, and 60 nm for Comparative Example 6. The produced coating films were immersed for 30 seconds in a solution of PGME and PGMEA, solvents used in photoresist solutions, mixed in a ratio of 7:3 (mass ratio). After removing the solvent by spin coating, the film thickness before and after immersion was compared to confirm insolubility in the solvent. The measurement results indicated that the film thickness reduction was 2% or less, indicating insolubility, and "×" indicated that it was soluble, indicating a reduction of more than 2%. The results are shown in Table 2 below.

[0141] (Resistance Test to Basic Hydrogen Peroxide Aqueous Solution) Using the resist underlayer film forming compositions prepared in Examples 1 to 7, Comparative Examples 1 to 2, and Comparative Examples 5 to 6, the compositions were applied by spin coating onto silicon substrates on which a 50 nm thick titanium nitride film had been formed on the surface, and the coating films were fired at 220°C to create the coating films. In addition, the coating films were immersed in a basic hydrogen peroxide aqueous solution with the composition shown in Table 1 below at the temperature shown in the same table for 1 minute and 30 seconds, and then the condition of the coating films after rinsing with water and drying was visually observed. The results are shown in Table 2 below. In Table 2, "×" indicates that the film peeled off, and "〇" indicates that the film did not peel off.

[0142]

[0143] (Storage Stability Test) Samples prepared using the resist underlayer film-forming compositions prepared in Examples 1 to 7 and Comparative Examples 1 to 2 were stored at -20°C and 80°C for 1 day each and compared by gel permeation chromatography (hereinafter abbreviated as GPC). A GPC instrument manufactured by Tosoh Corporation was used for GPC measurement, and the measurement conditions were as described above.

[0144] GPC column; Column temperature: 40°C; Solvent: Tetrahydrofuran (THF); Flow rate: 0.35 ml / min; Standard sample: Polystyrene (manufactured by Tosoh Corporation)

[0145] Based on the GPC measurement results, the molecular weight change of the sample stored at 80°C compared to the sample stored at -20°C was calculated using the following formula (t1): (Percentage change in molecular weight) = 100 × {(Molecular weight Mw of the sample stored at 80°C) / (Molecular weight Mw of the sample stored at -20°C) - 1} ... (t1) Based on the results of the above calculation, samples with a change in the range of -1 to 1% were marked with "○", and all others were marked with "×". The results are shown in Table 2.

[0146] In Table 2, for items where satisfactory results were not obtained and the evaluation result was marked with "×", no further characteristic tests were performed, and therefore, "-" is indicated.

[0147] As shown in the results above, the resist underlayer film formation composition according to the present invention has been found to satisfy all of the following requirements: excellent resistance to semiconductor wet etching solutions, good coatability, rapid film curing, and good storage stability.

Claims

1. (A) A compound or polymer having a reactive group represented by the cyclic ether structure of the following formula (I): (B) A compound or polymer having a reactive group reactive with the reactive group in (A): (C) An ionic curing catalyst represented by the following formula (II-1), the following formula (II-2), or the following formula (II-3): and (D) A solvent, A resist underlayer film forming composition containing. (In formula (I), * represents a bonding site. n represents 1 or 2. When n = 1, X represents an ether bond, an ester bond, or an amide bond. When n = 2, X represents a nitrogen atom or an amide bond.) (In formulas (II-1) to (II-3), X － is an anion having no sulfonic acid structure or sulfonylimide structure. t is 0 or 1. When t = 0, Y ＋ in Y is a sulfur atom. When t = 1, Y ＋ in Y is a nitrogen atom or a phosphorus atom. R １ to R ７ are each independently a hydrogen atom, an alkoxy group having 1 to 10 carbon atoms, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 40 carbon atoms, an organic group containing an ether bond, an organic group containing a ketone bond, an organic group containing an ester bond, or a group combining them. Also, any two of R １ , R ２ , R ３ and R ４ may be bonded to each other to form a ring together with the sulfur, nitrogen or phosphorus atom in the formula, provided that the case where only R ７ is hydrogen is excluded. In addition, when t = 0, all of R １ to R ３ do not become hydrogen, and when t = 1, all of R １ to R ４ do not become hydrogen. R ８ is independently a non-hydrogen substituted body, and n is 1 to 5.) 2. The resist underlayer film forming composition according to claim 1, wherein the polymer in (A) is a polymer having a unit structure represented by the following formula (1-1). (In formula (1-1), Ar represents a benzene ring, a naphthalene ring, or an anthracene ring, R １ n1 represents a hydroxyl group, a mercapto group which may be protected by a methyl group, an amino group which may be protected by a methyl group, a halogeno group, or an alkyl group having 1 to 10 carbon atoms which may be substituted or interrupted by a heteroatom or substituted by a hydroxyl group, n1 represents an integer from 0 to 3, L １ represents a single bond or an alkylene group having 1 to 10 carbon atoms, n2 represents 1 or 2, E represents a group having an epoxy group or an oxetanyl group, T １ When n² = 1, it represents an alkylene group having 1 to 10 carbon atoms, which may be interrupted by an ether bond, ester bond, or amide bond, and T １ (When n² = 2, it represents a trivalent hydrocarbon group having 1 to 10 carbon atoms, which may be interrupted by a nitrogen atom or an amide bond.) 3. The resist underlayer film forming composition according to claim 1, wherein the polymer in (A) is a polymer having a unit structure represented by the following formula (1-3). (In formula (1-3), R １００ represents a hydrogen atom or a methyl group, n2 represents 1 or 2, E represents a group having an epoxy group or a group having an oxetanyl group, T ２ When n² = 1, it represents an alkylene group having 1 to 10 carbon atoms, which may be interrupted by an ether bond, an ester bond, or an amide bond. ２ (When n² = 2, it represents a trivalent hydrocarbon group having 1 to 10 carbon atoms, which may be interrupted by a nitrogen atom or an amide bond.) 4. The resist underlayer film forming composition according to claim 1, wherein the polymer of (B) is a polymer having a unit structure represented by the following formula (3-1). (In formula (3-1), T ４ R represents an alkyl group having 1 to 10 carbon atoms, which may be substituted with a hydrogen atom or a halogen group. ４ represents a halogen group, carboxyl group, nitro group, cyano group, methylenedioxy group, acetoxy group, methylthio group, alkoxy group having 1 to 9 carbon atoms, amino group which may be substituted with an alkyl group having 1 to 3 carbon atoms, or alkyl group having 1 to 10 carbon atoms which may be substituted with a hydroxyl group or a halogen group. r4 represents an integer from 0 to 3. n7 represents an integer from 0 to 2. a represents an integer from 1 to 6.

5. The resist underlayer film forming composition according to claim 1, wherein the compound (B) is a compound containing a thiol structure.

6. The resist underlayer film forming composition according to claim 1, wherein the compound (C) is an ionic curing catalyst represented by formula (II-1) or formula (II-2).

7. The resist underlayer film forming composition according to claim 1, wherein the solvent (D) comprises at least one solvent selected from the group consisting of propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, isopropyl alcohol, ethyl acetate, butyl acetate, and cyclohexanone.

8. A resist underlayer film characterized by being a fired product of a coated film made from the resist underlayer film forming composition described in any one of claims 1 to 7.

9. A method for manufacturing a substrate with a resist pattern, used in the manufacture of a semiconductor, comprising the steps of: applying a resist underlayer film forming composition according to any one of claims 1 to 7 onto a semiconductor substrate and firing it to form a resist underlayer film; and forming a resist film directly on the resist underlayer film or via another layer, and then exposing and developing it to form a resist pattern.

10. A method for manufacturing a semiconductor device, comprising the steps of: forming a resist underlayer film on a semiconductor substrate on which an inorganic film may be formed on the surface using a resist underlayer film forming composition according to any one of claims 1 to 7; forming a resist pattern directly or via another layer on the resist underlayer film; dry etching the resist underlayer film using the resist pattern as a mask to expose the surface of the inorganic film or the semiconductor substrate; and wet etching or cleaning the inorganic film or the semiconductor substrate using a semiconductor wet etching solution, using the dry-etched resist underlayer film as a mask.

Images