Composition for forming resist underlayer film, resist underlayer film, method for forming resist pattern, and method for manufacturing semiconductor device

Abstract

A composition for forming a resist underlayer film according to the present invention comprises: a resin (G) having a composite unit structure; and a solvent. The composite unit structure has a unit structure (A) having a benzene ring having one hydroxyl group, and a unit structure (B) having one or more carbon atoms. The unit structure (A) has a biphenyl skeleton in which the benzene ring and another benzene ring are bonded by a single bond, or has a biphenyl analog structure in which the benzene ring and another benzene ring are bonded through a divalent group. The resin (G) is obtained by a reaction that forms a covalent bond between a carbon atom constituting the benzene ring of the unit structure (A) and a carbon atom in the unit structure (B).

Description

Composition for forming a resist underlayer film, resist underlayer film, method for forming a resist pattern, and method for manufacturing a semiconductor device.

[0001] The present invention relates to a composition for forming a resist underlayer film, a resist underlayer film, a method for forming a resist pattern, and a method for manufacturing a semiconductor device.

[0002] In recent years, semiconductor manufacturing processes have advanced rapidly, and consequently, there is a strong demand for higher quality and improved properties of resist underlayer films (see, for example, Patent Documents 1 to 6). In particular, for resist underlayer films known as high-carbon materials, there is a strong demand for improved etching resistance.

[0003] U.S. Patent Application Publication No. 2016 / 311975 Specification International Publication No. 2018 / 198960 Brochure JP 2021-81686 JP 2020-105513 International Publication No. 2013 / 146670 Brochure JP 2016-151024

[0004] However, creating a material that achieves both properties such as applicability to stepped substrates and planarization, as well as etching resistance, is extremely difficult, and there is still room for improvement as a material. The present invention has been made in view of the above circumstances, and aims to provide a resist underlayer film formation composition that satisfies etching resistance, applicability to stepped substrates, and planarization in a balanced manner, as well as a resist underlayer film formation method, resist pattern formation method, and semiconductor device manufacturing method using the resist underlayer film formation composition.

[0005] The inventors of the present invention conducted diligent research to solve the above problems and, as a result, found that they could solve the above problems, and completed the present invention having the following gist.

[0006] That is, the present invention includes the following aspects. [1] A composition for forming a resist underlayer film, comprising a resin (G) having a composite unit structure and a solvent, wherein the composite unit structure has a unit structure (A) having a benzene ring having one hydroxy group and a unit structure (B) having one or more carbon atoms, and the unit structure (A) has a biphenyl skeleton in which the benzene ring is bonded to another benzene ring by a single bond, or a biphenyl analog structure in which the benzene ring is bonded to another benzene ring via a divalent group, and the resin (G) is a resin obtained by a reaction that generates a covalent bond between a carbon atom constituting the benzene ring of the unit structure (A) and a carbon atom in the unit structure (B). [2] The composition for forming a resist underlayer film according to [1], wherein the resin (G) includes any one or two of the composite unit structures represented by the following formula (1a) and the following formula (1b). (In formula (1a) and formula (1b), R １ and R ２ each independently represents an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a halogen atom, R ３ and R ４ each independently represents a hydrogen atom, an aromatic hydrocarbon group which may have a substituent other than a hydroxy group, or an aliphatic hydrocarbon group which may have a substituent other than a hydroxy group, and when R ３ and R ４ bonded to the same carbon atom each represent an aromatic hydrocarbon group which may have a substituent other than a hydroxy group, they may be bonded to each other to form a fluorene ring, and when R ３ and R ４ bonded to the same carbon atom each represent an aliphatic hydrocarbon group which may have a substituent other than a hydroxy group, they may be bonded to each other to form an aliphatic hydrocarbon ring, k1 and k2 each independently represent 0 or 1, m1 and m2 each independently represent 0 to 3, (k1 + k2) is 1, and X is a single bond, -O-, -S-, -COO-, -CO-, -SS-, -SO ２-or represents an alkylene group having 1 to 6 carbon atoms.) [3] The resist underlayer film forming composition according to [2], wherein the substituents that the aromatic hydrocarbon group and the aliphatic hydrocarbon group may have in formula (1a) and formula (1b) are one or more groups selected from halogen atoms, alkyl groups, alkenyl groups, alkynyl groups, alkoxy groups, aryl groups, aryloxy groups, formyl groups, cyano groups, nitro groups, tertiary amino groups, ester groups, sulfide-containing groups and ether bond-containing groups. [4] The resist underlayer film forming composition according to [2] or [3], wherein the aromatic hydrocarbon group in formula (1a) and formula (1b) is a phenyl group or a naphthyl group. [5] The resist underlayer film forming composition according to any one of [2] to [4], wherein the aliphatic hydrocarbon group in formula (1a) and formula (1b) is an alkyl group having 1 to 10 carbon atoms. [6] The resist underlayer film forming composition according to any one of [1] to [5], wherein the resin (G) is a resin synthesized by polymerizing at least one compound having the biphenyl skeleton or the biphenyl analog structure with at least one aromatic ketone or aliphatic ketone in the presence of an acid catalyst. [7] The resist underlayer film forming composition according to any one of [1] to [6], wherein the solvent comprises a solvent with a boiling point of 160°C or higher. [8] The resist underlayer film forming composition according to any one of [1] to [7], further comprising at least one selected from the group consisting of acids and salts thereof, and acid generators. [9] The resist underlayer film forming composition according to any one of [1] to [8], further comprising a crosslinking agent.

[10] The resist underlayer film forming composition according to [9], wherein the crosslinking agent is at least one selected from the group consisting of aminoplast crosslinking agents and phenoplast crosslinking agents.

[11] The resist underlayer film forming composition according to any one of [1] to

[10] , further comprising a surfactant.

[12] A resist underlayer film on a semiconductor substrate, which is a cured product of the resist underlayer film forming composition described in any of [1] to

[11] .

[13] A method for forming a resist pattern used in semiconductor manufacturing, comprising the step of applying the resist underlayer film forming composition described in any of [1] to

[11] onto a semiconductor substrate and firing it to form a resist underlayer film.

[14] A method for manufacturing a semiconductor device, comprising the steps of: forming a resist underlayer film on a semiconductor substrate using a resist underlayer film forming composition according to any one of [1] to

[11] ; forming a resist film on the resist underlayer film; forming a resist pattern by irradiating the resist film with light or an electron beam and developing it; etching the resist underlayer film through the resist pattern to form a patterned resist underlayer film; and processing a semiconductor substrate through the patterned resist underlayer film.

[15] A method for manufacturing a semiconductor device, comprising the steps of: forming a resist underlayer film on a semiconductor substrate using a resist underlayer film forming composition according to any one of [1] to

[11] ; forming a hard mask on the resist underlayer film; further forming a resist film on the hard mask; forming a resist pattern by irradiating the resist film with light or an electron beam and developing it; etching the hard mask through the resist pattern to form a patterned hard mask; etching the resist underlayer film through the patterned hard mask to form a patterned resist underlayer film; and processing a semiconductor substrate through the patterned resist underlayer film.

[16] A method for manufacturing a semiconductor device, comprising the steps of: forming a resist underlayer film on a semiconductor substrate using a resist underlayer film forming composition according to any one of [1] to

[11] ; forming a hard mask on the resist underlayer film; further forming a resist film on the hard mask; forming a resist pattern by irradiating the resist film with light or an electron beam and developing it; etching the hard mask through the resist pattern to form a patterned hard mask; etching the resist underlayer film through the patterned hard mask to form a patterned resist underlayer film; removing the hard mask; and processing the semiconductor substrate through the patterned resist underlayer film.

[17] A method for manufacturing a semiconductor device, comprising the steps of: forming a resist underlayer film on a semiconductor substrate using a resist underlayer film forming composition according to any one of [1] to

[11] ; forming a hard mask on the resist underlayer film; further forming a resist film on the hard mask; forming a resist pattern by irradiating the resist film with light or an electron beam and developing it; etching the hard mask through the resist pattern to form a patterned hard mask; etching the resist underlayer film through the patterned hard mask to form a patterned resist underlayer film; removing the hard mask; forming a vapor-deposited film on the resist underlayer film after removal of the hard mask; processing the vapor-deposited film by etching; removing the patterned resist underlayer film to leave a patterned vapor-deposited film; and processing the semiconductor substrate through the patterned vapor-deposited film.

[18] A method for manufacturing a semiconductor device according to any one of

[15] to

[17] , wherein the hard mask is formed by coating a composition containing an inorganic substance or by vapor deposition of an inorganic substance.

[19] A method for manufacturing a semiconductor device according to any one of

[14] to

[18] , wherein the resist film is patterned by nanoimprint or self-assembled film.

[20] A method for manufacturing a semiconductor device according to

[16] or

[17] , wherein the hard mask is removed by dry etching or an alkaline chemical solution.

[0007] According to the present invention, it is possible to provide a resist underlayer film formation composition that satisfies etching resistance, coatability on stepped substrates, and planarization properties in a balanced manner, as well as a resist underlayer film formation method, resist pattern formation method, and semiconductor device manufacturing method using the resist underlayer film formation composition.

[0008] [Composition for forming a resist underlayer film] The resist underlayer film composition of the present invention comprises a resin (G) having a composite unit structure and a solvent. The composite unit structure comprises a unit structure (A) having a benzene ring having one hydroxyl group and a unit structure (B) having one or more carbon atoms. Unit structure (A) has a biphenyl skeleton in which the benzene ring and other benzene rings are bonded by a single bond, or a biphenyl analog structure in which the benzene ring and other benzene rings are bonded via a divalent group. Resin (G) is a resin obtained by a reaction that generates a covalent bond between the carbon atoms constituting the benzene ring of unit structure (A) and the carbon atoms in unit structure (B). In this specification, resin (G) may be referred to as "novolac resin". By containing the above-described unit structure (A) and unit structure (B), resin (G) can provide a resist underlayer film composition that satisfies etching resistance, coatability on stepped substrates, and planarization properties in a well-balanced manner.

[0009] The unit structure (A) has at least one of the following: a biphenyl skeleton in which a benzene ring having one hydroxyl group and a benzene ring without a hydroxyl group are bonded by a single bond; a biphenyl analog structure in which a benzene ring having one hydroxyl group and a benzene ring without a hydroxyl group are bonded via a heteroatom such as an oxygen atom or a sulfur atom; or a biphenyl analog structure in which a benzene ring having one hydroxyl group and a benzene ring without a hydroxyl group are bonded via an alkylene group. Here, "biphenyl analog structure" refers to a structure in which two benzene rings are bonded by a divalent group.

[0010] Unit structure (B) is, for example, a unit structure derived from an aldehyde compound or an aldehyde equivalent. An aldehyde equivalent is an organic compound that enables covalent bonding with an aromatic ring and is an organic compound having a ketone group; an acetal group; a ketal group; a hydroxyl or alkoxy group bonded to a secondary or tertiary carbon atom; a hydroxyl, alkoxy, or halo group bonded to the α-carbon of an alkylaryl group; or a carbon-carbon unsaturated bond. However, unit structure (B) does not have a hydroxyl group as a substituent.

[0011] [I. Definitions of Terms] In this specification, the definitions of the main terms relating to novolac resin, which is one aspect of the present invention, are described below. Unless otherwise specified, the following definitions of terms apply to novolac resin.

[0012] (I-1) "Novolac Resin" The term "novolac resin" is used in a broad sense to broadly include not only phenol-formaldehyde resins in the narrow sense (so-called novolac-type phenolic resins) and aniline-formaldehyde resins (so-called novolac-type aniline resins), but also resins formed by the covalent bonding (substitution reaction, addition reaction, condensation reaction, or addition-condensation reaction, etc.) between an organic compound having a functional group that enables covalent bonding with an aromatic ring [for example, an aldehyde group; a ketone group; an acetal group; a ketal group; a hydroxyl group or alkoxy group bonded to a secondary or tertiary carbon atom; a hydroxyl group, alkoxy group or halo group (halogen atom) bonded to the α-carbon atom (benzyl carbon atom, etc.) of an alkylaryl group; a carbon-carbon unsaturated bond such as that found in divinylbenzene or dicyclopentadiene] and an aromatic ring in a compound having an aromatic ring (preferably having heteroatoms such as oxygen atoms, nitrogen atoms, and sulfur atoms as atoms constituting the aromatic ring or atoms bonded to the aromatic ring).

[0013] Therefore, the novolac resin referred to in this specification is formed by linking multiple compounds having aromatic rings, through which an organic compound containing carbon atoms derived from the functional group (sometimes called a "linked carbon atom") forms a covalent bond with the aromatic ring in a compound having an aromatic ring via the linked carbon atoms, thereby forming a resin.

[0014] In this specification, the terms unit structure (A) and unit structure (B) are used to refer to the unit structures constituting "novolac resin". Unit structure (A) is a unit structure derived from a compound having an aromatic ring. Unit structure (B) is a unit structure derived from a compound having a functional group that enables covalent bonding with the aromatic ring of unit structure (A).

[0015] (I-2) "Residue" A "residue" refers to an organic group in which a hydrogen atom bonded to a carbon atom or heteroatom (such as a nitrogen atom, oxygen atom, or sulfur atom) is replaced by a bonding position. It may be a monovalent or polyvalent group. For example, replacing one hydrogen atom with one bonding position results in a monovalent organic group, while replacing two hydrogen atoms with bonding positions results in a divalent organic group.

[0016] (I-3) "Aromatic Ring" (Aromatic Group, Aryl Group, Arylene Group) The term "aromatic ring" is a concept that encompasses aromatic hydrocarbon rings, aromatic heterocycles, and their residues [sometimes called "aromatic group," "aryl group" (in the case of a monovalent group), or "arylene group" (in the case of a divalent group)], and includes not only monocyclic (aromatic monocyclic) but also polycyclic (aromatic polycyclic). In the case of a polycyclic, at least one monocycle is an aromatic monocycle, but the remaining monocycles that form a fused ring with the aromatic monocycle may be monocyclic heterocycles (heteromonocycles) or monocyclic alicyclic hydrocarbons (alicyclic monocycles). In this specification, heteroaryl groups are included in aryl groups. Heteroarylene groups are included in arylene groups.

[0017] Aromatic rings include aromatic hydrocarbon rings such as benzene, indene, naphthalene, azulene, styrene, toluene, xylene, mesitylene, cumene, anthracene, phenanthrene, triphenylene, benzoanthracene, pyrene, chrysene, fluorene, biphenyl, corannellene, perylene, fluorantene, benzo[k]fluorantene, benzo[b]fluorantene, benzo[gh]perylene, coronene, dibenzo[g,p]chrysene, acenaphthylene, acenaphthene, naphthacene, pentacene, cyclooctatetraene, and more typically aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and pyrene; and furan, pyran, pyridine, pyrimidine, pyrazine, thiophene, pyro Aromatic heterocyclic compounds such as furan, thiophene, pyrrole, N-alkylpyrrole, N-arylpyrrole, imidazole, pyridine, pyrimidine, pyrazine, triazine, thiazole, indole, phenylindole, bisindolefluorene, bisindolebenzofluorene, bisindoledibenzofluorene, purine, quinoline, isoquinoline, chromene, thiantrene, phenothiazine, phenoxazine, xanthene, acridine, phenazine, carbazole, and indolocarbazole are examples, but are not limited to these.

[0018] Aromatic rings (e.g., benzene rings, naphthalene rings, etc.) may optionally have substituents, but examples of such substituents include the following atoms and groups: • Halogen atoms • Saturated or unsaturated linear, branched or cyclic hydrocarbon groups (-R) which may be interrupted once or more by oxygen atoms in the hydrocarbon chain. ａ ) (including alkyl groups, alkenyl groups, and alkynyl groups (e.g., propargyl groups), and aryl groups, which may be interrupted once or more by oxygen atoms in the middle of the hydrocarbon chain.), -OR (where R is the hydrocarbon group -R) ａ ) ・Aryloxy group ・Formyl group ・Cyano group ・Nitro group ・Tertiary amino group (-NR ２The two R groups may be the same or different from each other. ａ ) ・Ester group (for example, -CO ２ R or -OCOR, where R is the hydrocarbon group -R ａ This represents: ) ・Sulfide-containing group (-SR, where R is the hydrocarbon group -R ａ (This represents...) ・Organic group containing an ether bond [R １１ -O-R １１ (R １１ Each of these independently represents an alkyl group having 1 to 6 carbon atoms, such as a methyl group or an ethyl group, or an aryl group, such as a phenyl group, a naphthyl group, anthranyl group, or a pyrenyl group. ) Residues of ether compounds represented by ; for example, organic groups containing ether bonds, including methoxy, ethoxy, and phenoxy groups.

[0019] The term "aromatic ring" further includes organic groups having a fused ring of one or more aromatic rings (such as benzene, naphthalene, anthracene, and pyrene) and one or more aliphatic or heterocyclic rings. Examples of aliphatic rings include cyclobutane, cyclobutene, cyclopentane, cyclopentene, cyclohexane, cyclohexene, methylcyclohexane, methylcyclohexene, cycloheptane, and cycloheptene, while examples of heterocyclic rings include furan, thiophene, pyrrole, imidazole, pyran, pyridine, pyrimidine, pyrazine, pyrrolidine, piperidine, piperazine, and morpholine.

[0020] An "aromatic ring" may also be an organic group having a structure in which two or more aromatic rings are linked by a divalent linking group. Examples of divalent linking groups include alkylene groups, arylene groups, -NH-, -NHCO-, -O-, -COO-, -CO-, -S-, -SS-, and -SO ２ - are some examples. In addition, the divalent linking group may be a divalent group obtained by removing one hydrogen atom from any substituent of the aromatic ring mentioned above.

[0021] (I-4) "Heterocycle" The term "heterocycle" encompasses both aliphatic heterocycles and aromatic heterocycles, and includes not only monocyclic (heteromonocyclic) but also polycyclic (heteropolycyclic) compounds. In the case of polycyclic compounds, at least one monocycle is a heteromonocycle, but the remaining monocycles may be aromatic hydrocarbon monocycles or alicyclic monocycles. Examples of aromatic heterocycles can be found in (I-3) above. Similar to the aromatic rings in (I-3) above, they may have substituents.

[0022] (I-5) "Non-aromatic ring" (aliphatic ring) When the "non-aromatic ring" is a monocyclic ring, the "non-aromatic monocyclic ring" refers to a monocyclic hydrocarbon that does not belong to the aromatic group, and is typically a monocyclic alicyclic compound. It may also be called an aliphatic monocyclic ring (which may include aliphatic heterocyclic rings, and may contain unsaturated bonds as long as it does not belong to the aromatic compound). Similar to the aromatic ring in (I-3) above, it may have substituents.

[0023] Examples of non-aromatic monocyclic compounds (aliphatic rings, aliphatic monocyclic compounds) include cyclopropane, cyclobutane, cyclobutene, cyclopentane, cyclopentene, cyclohexane, methylcyclohexane, cyclohexene, methylcyclohexene, cycloheptane, and cycloheptene.

[0024] When the "non-aromatic ring" is polycyclic, "non-aromatic polycyclic" refers to a polycyclic hydrocarbon that does not belong to the aromatic group, and is typically a polycyclic alicyclic compound. It may also be called an aliphatic polycyclic [which may include aliphatic heterocyclics (where at least one of the monocyclic rings is an aliphatic heterocyclic ring), or it may contain unsaturated bonds as long as it does not belong to the aromatic compound]. It includes non-aromatic dicyclic, non-aromatic tricyclic, and non-aromatic tetracyclic compounds.

[0025] When "non-aromatic ring" refers to a bicyclic non-aromatic ring, it is a fused ring composed of two monocyclic hydrocarbons that do not belong to the aromatic group, and is typically a fused ring of two alicyclic compounds. In this specification, it may also be called an aliphatic bicyclic ring (which may include aliphatic heterocyclic rings, and may contain unsaturated bonds as long as they do not belong to the aromatic group). Examples of non-aromatic bicyclic rings include bicyclopentane, bicyclooctane, and bicycloheptene.

[0026] When "non-aromatic ring" refers to a tricyclic compound, it is a fused ring composed of three monocyclic hydrocarbons that do not belong to the aromatic group. Typically, it is a fused ring of three alicyclic compounds (each of which may be a heterocyclic compound, and may contain unsaturated bonds as long as they do not belong to the aromatic group). Examples of non-aromatic tricyclic compounds include tricyclooctane, tricyclononane, and tricyclodecane.

[0027] When "non-aromatic ring" refers to a tetracyclic compound, it is a fused ring composed of four monocyclic hydrocarbons that do not belong to the aromatic group. Typically, it is a fused ring of four alicyclic compounds (each of which may be a heterocyclic compound, and may contain unsaturated bonds as long as they do not belong to the aromatic group). Examples of non-aromatic tetracyclic compounds include hexadecahydropyrene.

[0028] (I-6) "Carbon atoms constituting a ring (part)" means carbon atoms constituting a hydrocarbon ring (which may be an aromatic ring, an aliphatic ring, or a heterocycle) in an unsubstituted state.

[0029] (I-7) A "hydrocarbon group" is a group formed by removing one or more hydrogen atoms from a hydrocarbon, and such hydrocarbons include saturated or unsaturated aliphatic hydrocarbons, saturated or unsaturated alicyclic hydrocarbons, and aromatic hydrocarbons.

[0030] (I-8) In the chemical structural formulas showing the unit structure of novolac resin in this specification, bonds (indicated by *) may be shown for convenience, but unless otherwise specified, such bonds can take any bondable position in the unit structure and do not limit the bondable position in the unit structure in any way.

[0031] <Resin (G)> Resin (G) has a composite unit structure. The composite unit structure has a unit structure (A) having a benzene ring with one hydroxyl group and a unit structure (B) having one or more carbon atoms.

[0032] The composite unit structure of resin (G) can be represented, for example, by the following formula (AB). (In equation (AB), A represents unit structure (A), and B represents unit structure (B).)

[0033] <<A-1: Unit Structure (A)>> Unit structure (A) has a benzene ring having one hydroxyl group. Unit structure (A) has a biphenyl skeleton in which the benzene ring and another benzene ring are linked by a single bond, or a biphenyl analog structure in which the benzene ring and another benzene ring are linked via a divalent group. That is, unit structure (A) has a biphenyl skeleton in which two benzene rings are linked by a single bond, or a biphenyl analog structure in which two benzene rings are linked by a divalent group, and the biphenyl skeleton or the biphenyl analog structure has one hydroxyl group. The unit structure (A) has, for example, at least one of the following: a biphenyl skeleton in which a benzene ring having one hydroxyl group and a benzene ring without a hydroxyl group are bonded by a single bond; a biphenyl analog structure in which a benzene ring having one hydroxyl group and a benzene ring without a hydroxyl group are bonded via a heteroatom such as an oxygen atom or a sulfur atom; or a biphenyl analog structure in which a benzene ring having one hydroxyl group and a benzene ring without a hydroxyl group are bonded via an alkylene group. By having a biphenyl skeleton having one hydroxyl group or a biphenyl analog structure having one hydroxyl group in the unit structure (A), a suitable viscosity is maintained for the resist underlayer film forming composition containing resin (G), and a resist underlayer film forming composition that satisfies etching resistance, coatability on stepped substrates, and planarization properties in a well-balanced manner is obtained.

[0034] The number of carbon atoms in the unit structure (A) is not particularly limited, but for example, it is 12 to 30, and preferably 12 to 18.

[0035] The unit structure (A) is, for example, a residue obtained by removing two hydrogen atoms from a biphenyl skeleton or a biphenyl analog structure. The biphenyl skeleton is derived, for example, from a compound having a biphenyl skeleton used in the synthesis of resin (G). The biphenyl analog structure is derived, for example, from a compound having a biphenyl analog structure used in the synthesis of resin (G).

[0036] The biphenyl skeleton or biphenyl analog structure may have substituents. Examples of substituents include halo groups (halogen atoms), alkyl groups, alkenyl groups, alkynyl groups, alkoxy groups, aryl groups, aryloxy groups, formyl groups, cyano groups, nitro groups, tertiary amino groups, ester groups, sulfide-containing groups, ether-bond-containing groups, etc. Examples of alkyl groups include linear, branched, or cyclic alkyl groups having 1 to 30 carbon atoms. Examples of alkenyl groups include linear, branched, or cyclic alkenyl groups having 2 to 10 carbon atoms. Examples of alkoxy groups include groups represented by -OR, where R is a saturated or unsaturated linear, branched, or cyclic hydrocarbon group (-R) which may be interrupted once or more times by an oxygen atom in the hydrocarbon chain. ａ ) represents. Examples of the number of carbon atoms in an alkoxy group include 1 to 10. Examples of aryl groups include aryl groups with 6 to 30 carbon atoms. Examples of aryloxy groups include aryloxy groups with 6 to 30 carbon atoms. Examples of tertiary amino groups include -NR ２ A group represented by is an example. Here, the two Rs may be the same or different hydrocarbon group -R ａ This represents the ester group, -CO ２ A group represented by R or -OCOR is an example. Here, R is the hydrocarbon group -R ａ This represents the sulfide-containing group, where R is the hydrocarbon group -R. ａ This represents the ether bond-containing group, R １１ -O-R １１ Examples include residues of ether compounds containing an ether bond represented by . Here, R １１ Each of these independently represents an alkyl group having 1 to 6 carbon atoms, such as a methyl group or an ethyl group, or an aryl group, such as a phenyl group, a naphthyl group, anthranyl group, or a pyrenyl group. The ether bond-containing group may be an organic group containing an ether bond, such as a methoxy group, an ethoxy group, or a phenoxy group.

[0037] <<A-2: Examples of skeletons constituting the unit structure (A)>> The biphenyl skeleton refers to a skeleton containing a biphenyl group. The two benzene rings in the biphenyl group may each independently have substituents, be linked to other aromatic hydrocarbon rings, or be fused to other aromatic hydrocarbon rings. Examples of other aromatic hydrocarbon rings include benzene rings, naphthalene rings, anthracene rings, phenanthrene rings, tetracene rings, tetrafen rings, chrysene rings, triphenylene rings, pyrene rings, pentacene rings, hexacene rings, etc. An example of a biphenyl skeleton is a skeleton represented by the following formula (G0). These aromatic rings may have substituents.

[0038] A biphenyl analog structure is a structure in which two benzene rings are linked by a divalent group. Examples of divalent groups include -O-, -S-, -COO-, -CO-, -SS-, and -SO ２ - Examples include alkylene groups having 1 to 6 carbon atoms. Biphenyl analog structures include those in which the single bonds in the skeleton represented by the above formula (G0) are replaced with divalent groups.

[0039] The resin (G) preferably contains one or two of the composite unit structures represented by the following formulas (1a) and (1b) as a composite unit structure. (In equations (1a) and (1b), R １ and R ２ Each of these independently represents an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a halogen atom, R ３ and R ４ Each of these independently represents a hydrogen atom, an aromatic hydrocarbon group which may have substituents other than a hydroxyl group, or an aliphatic hydrocarbon group which may have substituents other than a hydroxyl group, and is bonded to the same carbon atom R ３ and R ４When each represents an aromatic hydrocarbon group which may have substituents other than a hydroxyl group, they may bond to each other to form a fluorene ring, and R bonded to the same carbon atom ３ and R ４ When each represents an aliphatic hydrocarbon group which may have substituents other than hydroxyl groups, they may bond to each other to form an aliphatic hydrocarbon ring, k1 and k2 each independently represent 0 or 1, m1 and m2 each independently represent 0 to 3, (k1 + k2) is 1, and X is a single bond, -O-, -S-, -COO-, -CO-, -SS-, -SO ２ (- Or it represents an alkylene group with 1 to 6 carbon atoms.)

[0040] In formulas (1a) and (1b), the biphenyl skeleton or biphenyl analog structure containing X corresponds to the unit structure (A), and R ３ , R ４ , and R ３ and R ４ The carbon atom bonded to it corresponds to the unit structure (B). ３ and R ４ The carbon atoms that bond with it are, for example, the carbon atoms that bond with the carbon atoms constituting the benzene ring in the biphenyl skeleton or biphenyl analog structure of the unit structure (A).

[0041] Examples of alkyl groups having 1 to 30 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, and 1-ethyl-n-propyl group. 1,1-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, 2,2Examples include 3-trimethylcyclopropyl group, 1-ethyl-2-methylcyclopropyl group, 2-ethyl-1-methylcyclopropyl group, 2-ethyl-2-methylcyclopropyl group, 2-ethyl-3-methylcyclopropyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-dodecyl group, n-tetradecyl group, n-hexadecyl group, n-octadecyl group, n-icosyl group, n-docosyl group, n-tetracosyl group, n-hexacosyl group, n-octacosyl group, n-triacontyl group, norbornyl group, adamantyl group, etc.

[0042] Examples of alkenyl groups having 2 to 10 carbon atoms include ethenyl group, 1-propenyl group, 2-propenyl group, 1-methyl-1-ethenyl group, 1-butenyl group, 2-butenyl group, 3-butenyl group, 2-methyl-1-propenyl group, 2-methyl-2-propenyl group, 1-ethylethenyl group, 1-methyl-1-propenyl group, 1-methyl-2-propenyl group, 1-pentenyl group, 2-pentenyl group, 3-pentenyl group, 4-pentenyl group, 1-n-propylethenyl group, 1-methyl-1-butenyl group, 1-methyl-2-butenyl group, and 1-methyl-3-butenyl group. Nyl group, 2-ethyl-2-propenyl group, 2-methyl-1-butenyl group, 2-methyl-2-butenyl group, 2-methyl-3-butenyl group, 3-methyl-1-butenyl group, 3-methyl-2-butenyl group, 3-methyl-3-butenyl group, 1,1-dimethyl-2-propenyl group, 1-i-propylethenyl group, 1,2-dimethyl-1-propenyl group, 1,2-dimethyl-2-propenyl group, 1-cyclopentenyl group, 2-cyclopentenyl group, 3-cyclopentenyl group, 1-hexenyl group, 2-hexenyl group, 3-hexenyl group, 4-hexenyl group, 5-hexenyl group Xenyl group, 1-methyl-1-pentenyl group, 1-methyl-2-pentenyl group, 1-methyl-3-pentenyl group, 1-methyl-4-pentenyl group, 1-n-butylethenyl group, 2-methyl-1-pentenyl group, 2-methyl-2-pentenyl group, 2-methyl-3-pentenyl group, 2-methyl-4-pentenyl group, 2-n-propyl-2-propenyl group, 3-methyl-1-pentenyl group, 3-methyl-2-pentenyl group, 3-methyl-3-pentenyl group, 3-methyl-4-pentenyl group, 3-ethyl-3-butenyl group, 4-methyl-1-pentenyl group, 4-methyl-2-pentenyl group, 4-methyl-3-pentenyl group, 4-methyl-4-pentenyl group, 1,1-dimethyl-2-butenyl group, 1,1-dimethyl-3-butenyl group, 1,2-dimethyl-1-butenyl group, 1,2-dimethyl-2-butenyl group, 1,2-dimethyl-3-butenyl group, 1-methyl-2-ethyl-2-propenyl group, 1-s-butylethenyl group, 1,3-dimethyl-1-butenyl group, 1,3-dimethyl-2-butenyl group, 1,3-dimethyl-3-butenyl group, 1-i-butylethenyl group, 2,2-dimethyl-3-butenyl group, 2,3-dimethyl-1-butenyl group, 2,3-dimethyl-2-butenyl group, 2,3-dimethyl-3-butenyl group, 2-i-propyl-2-propenyl group, 3,3-dimethyl-1-butenyl group, 1-ethyl-1-butenyl group, 1-ethyl-2-butenyl group, 1-ethyl-3-butenyl group, 1-n-propyl-1-propenyl group, 1-n-propyl-2-propenyl group, 2-ethyl-1-butenyl group, 2-ethyl-2-butenyl group, 2-ethyl-3-butenyl group, 1,1,2-trimethyl-2-propenyl group, 1-tert-butylethenyl group, 1-methyl-1-ethyl-2-propenyl group, 1-ethyl-2-methyl-2-propenyl group, 1-ethyl-2-methyl-2-propenyl group Examples include penyl group, 1-i-propyl-1-propenyl group, 1-i-propyl-2-propenyl group, 1-methyl-2-cyclopentenyl group, 1-methyl-3-cyclopentenyl group, 2-methyl-1-cyclopentenyl group, 2-methyl-2-cyclopentenyl group, 2-methyl-3-cyclopentenyl group, 2-methyl-4-cyclopentenyl group, 2-methyl-5-cyclopentenyl group, 3-methyl-1-cyclopentenyl group, 3-methyl-2-cyclopentenyl group, 3-methyl-3-cyclopentenyl group, 3-methyl-4-cyclopentenyl group, 3-methyl-5-cyclopentenyl group, 1-cyclohexenyl group, 2-cyclohexenyl group, and 3-cyclohexenyl group.

[0043] Examples of alkynyl groups having 2 to 10 carbon atoms include ethynyl group, 1-propynyl group, propargyl group (2-propynyl group), 1-butynyl group, 2-butynyl group, 3-butynyl group, 1-pentynyl group, 2-pentynyl group, 3-pentynyl group, 4-pentynyl group, 1-hexynyl group, 2-hexynyl group, 3-hexynyl group, 4-hexynyl group, and 5-hexynyl group.

[0044] 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-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, and 4-methyl- Examples include 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, cyclopentyloxy group, cyclohexyloxy group, norbornioxy group, adamantyloxy group, etc.

[0045] In formulas (1a) and (1b), the two benzene rings in the fluorene ring that may be formed may independently have substituents, be linked to other aromatic hydrocarbon rings, or be fused to other aromatic hydrocarbon rings. Examples of other aromatic hydrocarbon rings include benzene rings, naphthalene rings, anthracene rings, phenanthrene rings, tetracene rings, tetrafen rings, chrysene rings, triphenylene rings, pyrene rings, pentacene rings, hexacene rings, and the like. Examples of substituents include halo groups (halogen atoms), alkyl groups, alkenyl groups, alkynyl groups, alkoxy groups, aryl groups, aryloxy groups, formyl groups, cyano groups, nitro groups, tertiary amino groups, ester groups, sulfide-containing groups, and ether-bond-containing groups. Examples of halo groups include halogen atoms such as fluorine, chlorine, bromine, and iodine. Examples of alkyl groups include linear, branched, or cyclic alkyl groups having 1 to 30 carbon atoms. Examples of alkenyl groups include linear, branched, or cyclic alkenyl groups having 2 to 10 carbon atoms. Examples of alkynyl groups include linear, branched, or cyclic alkynyl groups having 2 to 10 carbon atoms. Examples of alkoxy groups include groups represented by -OR, where R is a saturated or unsaturated linear, branched, or cyclic hydrocarbon group (-R) which may be interrupted once or more by an oxygen atom in the hydrocarbon chain. ａ ) represents. Examples of alkoxy groups include those with 1 to 10 carbon atoms. Examples of aryl groups include those with 6 to 30 carbon atoms. Examples of aryl groups with 6 to 30 carbon atoms include phenyl, tolyl, o-xylyl, biphenyl, naphthyl, anthracenyl, phenantrenyl, chrysenyl, triphenylenyl, and pyrenyl groups. Examples of aryloxy groups include those with 6 to 30 carbon atoms. Examples of aryloxy groups with 6 to 30 carbon atoms include phenoxy, benzyloxy, and 1-naphthyloxy groups. Examples of tertiary amino groups include -NR ２ A group represented by is an example. Here, the two Rs may be the same or different hydrocarbon group -Rａ This represents the ester group, -CO ２ A group represented by R or -OCOR is an example. Here, R is the hydrocarbon group -R ａ This represents the sulfide-containing group, where R is the hydrocarbon group -R. ａ This represents the ether bond-containing group, R １１ -O-R １１ Examples include residues of ether compounds containing an ether bond represented by . Here, R １１ Each of these independently represents an alkyl group having 1 to 6 carbon atoms, such as a methyl group or an ethyl group, or an aryl group, such as a phenyl group, a naphthyl group, anthranyl group, or a pyrenyl group. The ether bond-containing group may be an organic group containing an ether bond, such as a methoxy group, an ethoxy group, or a phenoxy group.

[0046] Examples of aliphatic hydrocarbon rings that may be formed in formulas (1a) and (1b) include cyclopropane rings, cyclobutane rings, cycloheptane rings, cyclohexane rings, bicyclopentane rings, bicyclooctane rings, and tricyclodecane rings.

[0047] In formulas (1a) and (1b), the aromatic hydrocarbon group is preferably a phenyl group, a naphthyl group (1-naphthyl group or 2-naphthyl group), a biphenyl group, or a diphenyl ether residue.

[0048] In formulas (1a) and (1b), alkyl groups having 1 to 10 carbon atoms are preferred as the aliphatic hydrocarbon group.

[0049] In formulas (1a) and (1b), m1 and m2 each independently represent 0 to 3, preferably 0 to 1. In formulas (1a) and (1b), X is a single bond, -O-, -S-, -COO-, -CO-, -SS-, -SO ２ - or an alkylene group having 1 to 6 carbon atoms, preferably a single bond, -O-, -S-, or a methylene group, and more preferably a single bond or -O-.

[0050] The unit structure (A) in resin (G) may include unit structures other than the biphenyl skeleton and biphenyl analog structures. Examples of unit structures other than the biphenyl skeleton and biphenyl analog structures include unit structures having an aromatic amine skeleton and unit structures having a nitrogen-containing aromatic heterocyclic skeleton. These unit structures may include the biphenyl skeleton or biphenyl analog structures.

[0051] <<<A-3-1: Aromatic Amine Skeleton>>> An aromatic amine skeleton refers to a skeleton having an aromatic ring and a nitrogen atom bonded to the aromatic ring but not constituting a ring. Examples of aromatic amine skeletons include those represented by the following formulas (A-1a) to (A-1c). As will be described later, in unit structure (A), the hydrogen atom of the NH group may be replaced by a substituent. Examples of substituents include those described in (I-3) "Aromatic Ring" above, and those described in (A-2) "Examples of Skeletons Constituting Unit Structure (A)" above. (In formulas (A-1a) to (A-1c), Ar １１ Each of these independently represents a residue of an aromatic ring. １１ Each of these independently represents a hydrogen atom or an aromatic ring residue.

[0052] Ar １１ and R １１ Examples of aromatic rings in the residues of the aromatic ring include aromatic rings represented by the following formula (G1). These aromatic rings may have substituents.

[0053] Examples of skeletons represented by formula (A-1a) include the following. The aromatic rings in these skeletons may have substituents, and the hydrogen atoms of the NH group may be replaced by substituents. The same applies to the following skeletons.

[0054] Examples of skeletons represented by formula (A-1b) include the following:

[0055] Examples of skeletons represented by formula (A-1c) include the following:

[0056] <<<A-3-2: Nitrogen-containing aromatic heterocyclic skeleton>>> A nitrogen-containing aromatic heterocyclic skeleton refers to a skeleton having an aromatic heterocyclic ring in which nitrogen atoms are present as atoms constituting the heterocyclic ring. Examples of nitrogen-containing aromatic heterocyclic rings include pyrrole rings, indole rings, carbazole rings, pyridine rings, acridine rings, phenoxazine rings, and phenothiazine rings. These nitrogen-containing aromatic heterocyclic rings may have substituents. Examples of nitrogen-containing aromatic heterocyclic skeletons include skeletons represented by the following formulas (A-2a), (A-2b-1), (A-2b-2), (A-2c-1), (A-2c-2), (A-2c-3), (A-2c-4), (A-2d), (A-2e), (A-3a), or (A-3b). As will be described later, in the unit structure (A), the hydrogen atoms of the NH group may be replaced by substituents. (In the formula, Ar ２１ Each of these independently represents a residue of an aromatic ring. ２１ Each of these independently represents a hydrogen atom or an aromatic ring residue. ２２ Each of these independently represents a hydrogen atom, a hydrocarbon group with 1 to 5 carbon atoms, or an aromatic ring residue. Two adjacent R ２２ These may together form an unsaturated aliphatic ring. Note that one of the unsaturated bonds in an unsaturated aliphatic ring refers to the unsaturated bond constituting the pyrrole ring. Each R independently represents a hydrogen atom, an aromatic ring residue, or a bond with L. L represents a single bond or a linking group. n1 represents 1, and n2 represents 1 or 2. In formulas (A-2b-2) and (A-2c-4), when L is a single bond, the substructures (In1) and (In2), and the substructures (Ca1) and (Ca2), are bonded by two nitrogen atoms or two Ar ２１ They are bonded together by bonding with each other, or by bonding between nitrogen atoms and Ar ２１The bond is formed by the combination of and . In formulas (A-2b-2) and (A-2c-4), when L is a linking group, L is N or Ar ２１ (It is connected to this.)

[0057] Ar ２１ , R ２１ , R ２２ Examples of aromatic rings in the residues of the aromatic ring of R include aromatic rings represented by the following formula (G2). These aromatic rings may have substituents.

[0058] Two adjacent R ２２ Examples of unsaturated aliphatic rings formed by these elements together include the following rings. These aliphatic rings may have substituents.

[0059] Examples of linking groups in L include saturated hydrocarbon groups with 1 to 5 carbon atoms and an (n1 + n2) valency, and residues obtained by removing (n1 + n2) hydrogen atoms from an aromatic ring.

[0060] <Formula (A-2d)> (In formula (A-2d), R １１ Each of these independently represents a hydrogen atom or an aromatic group, and Ar is an aromatic ring portion, each independently representing a benzene ring, a fused ring composed of two or three benzene rings, or a structure represented by the following formula (Ar01), X ０ These are single bonds, -O-, -S-, -NR １２ - or -CR １３ R １４ - represents R １２ R １１ Same as or different from R １１ It is the same as the definition of R １３ and R １４ Each of the following represents a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, where n is 1 or 2. When n is 1, Z represents a monovalent organic group, and when n is 2, Z represents a divalent organic group.

[0061] Furthermore, in the unit structure (A), R in formula (A-2d) １１ R may be a substituent.１１ When R is a substituent or an aromatic group １１ is, for example, (i) a methylol group, (ii) an aryl group having 6 to 30 carbon atoms, or (iii) a linear, branched or cyclic alkoxymethyl group having 2 to 20 carbon atoms; a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms; an alkenyl group having 2 to 10 carbon atoms; or an alkynyl group having 2 to 10 carbon atoms, provided that for (ii) and (iii) above, they may be further substituted with an oxygen atom-containing substituent, a sulfur atom-containing substituent, a nitrogen atom-containing substituent, an aryl group or a halo group, or for (iii) above, the hydrocarbon chain portion may be further interrupted with an oxygen atom-containing substituent, a sulfur atom-containing substituent, a nitrogen atom-containing substituent, an arylene group.

[0062] Examples of the skeleton represented by formula (A-2d) include, for example, the skeleton represented by the following formula (A-2d-1). (In formula (A-2d-1), R １１ , Ar, and X ０ are, respectively, the same as R １１ , Ar, and X ０ in formula (A-2d). R ２１ is an aryl group having 6 to 30 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or an alkynyl group having 2 to 10 carbon atoms.)

[0063] Ar in formula (A-2d) and formula (A-2d-1) is, for example, a benzene ring or a naphthalene ring. Ar in formula (A-2d) and formula (A-2d-1) may also be a structure represented by the following formula (Ar01). (In formula (Ar01), R １１ａ is the same as R １１ in formula (A-2d-1), R ２１ａ is the same as R ２１ in formula (A-2d-1), Ar ａ is the same as Ar in formula (A-2d-1), and X ０ａ is the same as X ０ in formula (A-2d-1). At two carbon atoms a and b, b and c, or c and d in formula (Ar01), X in formula (A-2d) or formula (A-2d-1) ０forms a condensed ring with a monocyclic moiety containing it.)

[0064] Here, X ０ The monocyclic moiety containing represents a monocyclic ring represented by the following formula (AP011) in formula (A-2d).

[0065] As the skeleton represented by formula (A-2d), the skeleton represented by the above formula (A-2d-1), the skeleton represented by the following formula (A-2d-2), and the skeleton represented by the following formula (A-2d-3) are preferable. (In formula (A-2d-2) and formula (A-2d-3), R １１ , Ar, and X ０ are respectively synonymous with R １１ , Ar, and X ０ in formula (A-2d). L represents a single bond or a divalent linking group. Examples of the divalent linking group include -O-, -S-, -SO ２ -, -CO-, -CONH-, -COO-, -NR １０１ -, ―(CR １０２ R １０３ )m １ -, -(Ar １０１ )m ２ -, -CH ２ -(Ar １０１ )m ２ -CH ２ -, or -(cyclo-R)-. R １０１ , R １０２ , and R １０３ each independently represent a hydrogen atom; a hydrocarbon group having 1 to 5 carbon atoms; or an aryl group having 6 to 30 carbon atoms; m １ represents an integer of 1 to 10. And Ar １０１ each independently represents an arylene group having 6 to 30 carbon atoms; m ２ represents an integer of 1 to 3 which is the number of aromatic rings bonded to each other by a single bond. "cyclo-R" represents a divalent alicyclic hydrocarbon group having 5 to 8 members, preferably 6 to 8 members, which may form a condensed ring with one or two benzene rings or naphthalene rings. R ２２Each of these independently represents an arylene group having 6 to 30 carbon atoms, an alkenylene group having 2 to 10 carbon atoms, or an alkynylene group having 2 to 10 carbon atoms, which may be substituted.

[0066] <Formula (A-2e)> (In formula (A-2e), L represents a single bond or a divalent linking group between any two carbon atoms constituting each azaaryl condensed ring, R １１ and R ２１ Each of these independently represents a hydrogen atom or an aromatic ring residue, and R １２ and R ２２ Each of these independently represents a substituent, and n1 and n2 independently represent R １２ and R ２２ This represents the number of substituents, and may be 0. １ and Ar ２ Each of these is a benzene ring or a fused ring composed of two or three benzene rings, each independently forming a fused ring with the pyrrole ring portion in formula (A-2e).

[0067] Furthermore, in the unit structure (A), R in formula (A-2e) １１ and R ２１ R may be a substituent. １１ and R ２１ If R is a substituent or an aromatic group residue, １１ and R ２１ For example, (i) a methylol group, (ii) an aryl group having 6 to 30 carbon atoms, or (iii) a linear, branched, or cyclic alkoxymethyl group having 2 to 20 carbon atoms; a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms; an alkenyl group having 2 to 10 carbon atoms; or an alkynyl group having 2 to 10 carbon atoms, provided that (ii) and (iii) are further substituted with an oxygen atom-containing substituent, a sulfur atom-containing substituent, a nitrogen atom-containing substituent, an aryl group, or a halo group, or (iii) may have its hydrocarbon chain further interrupted with an oxygen atom-containing substituent, a sulfur atom-containing substituent, a nitrogen atom-containing substituent, or an arylene group.

[0068] In formula (A-2e), L is a single bond or a divalent linking group. L may be bonded to any carbon atom constituting each azaaryl fused ring, and Ar １ Ar ２ That is, in the azaaryl condensed ring and It may be bonded to aromatic carbon atoms that make up the ring, but it is preferable that it is bonded to carbon atoms that make up the pyrrole ring portion in the azaaryl condensed ring.

[0069] Preferred linking groups (L) include -O-, -S-, and -SO ２ -, -CO-, -CONH-, -COO-, -NH-, -(CR １０２ R １０３ )m １ -, - (Ar １０１ )m ２ -ien-CH ２ - (Ar １０１ )m ２ -CH ２ Selected from the group consisting of - and - (cyclo-R) -. １０２ and R １０３ Each of these independently represents a hydrogen atom; a hydrocarbon group having 1 to 5 carbon atoms; or an aryl group having 6 to 30 carbon atoms; m １ represents integers from 1 to 10. And Ar １０１ Each of these represents an arylene group with 6 to 30 carbon atoms; m ２ is an integer from 1 to 3, which is the number of aromatic rings that are bonded to each other by single bonds. "cyclo-R" represents a divalent alicyclic hydrocarbon group of 5 to 8 members, preferably 6 to 8 members, which may form a fused ring with one or two benzene rings or naphthalene rings.

[0070] <Formulas (A-3a) and (A-3b)> (In the formula, Ar ３１ and Ar ３２ Each of these independently represents a residue in an aromatic ring, or together with the carbon atoms bonded to them, they represent a residue in an aromatic ring. X represents -O, -S-, -NH-, -CH ２ -ien-CH ２ -CH ２ (This represents -, or -CH=CH-.)

[0071] Ar ３１ and Ar ３２ Examples of aromatic rings in the residues of the aromatic ring include the aromatic ring represented by the aforementioned formula (G1). ３１ and Ar ３２ Examples of aromatic rings formed by these elements together with the carbon atoms bonded to them include fluorene rings, benzofluorene rings, and dibenzofluorene rings.

[0072] Examples of skeletons represented by formula (A-2a) include the following. The aromatic rings in these skeletons may have substituents, and the hydrogen atoms of the NH group may be replaced by substituents. The same applies to the following skeletons.

[0073] Examples of skeletons represented by formula (A-2b-1) include the following:

[0074] Examples of skeletons represented by formula (A-2b-2) include the following:

[0075] Examples of skeletons represented by formula (A-2c-1) include the following:

[0076] Examples of skeletons represented by formula (A-2c-2) or formula (A-2c-3) include the following:

[0077] Examples of skeletons represented by formula (A-2c-4) include the following:

[0078] Examples of skeletons represented by formula (A-2d) include the following:

[0079] Examples of skeletons represented by formula (A-2e) include the following. Note that there may be overlap between specific examples of skeletons represented by formula (A-2d) and specific examples of skeletons represented by formula (A-2e).

[0080] Examples of skeletons represented by formula (A-3a) include the following:

[0081] Examples of skeletons represented by formula (A-3b) include the following:

[0082] Other examples of nitrogen-containing aromatic heterocyclic skeletons include the following:

[0083] Furthermore, the H atoms of NH in the above-mentioned aromatic ring skeleton, and the hydrogen atoms bonded to the aromatic ring in the aromatic ring skeleton, may be replaced with substituents. Examples of such substituents include the substituents described in (I-3) "Aromatic Ring" above, and the substituents described in (A-2) "Examples of Skeletons Constituting Unit Structure (A)" above.

[0084] <<B-1: Unit Structure (B)>> Unit structure (B) has one or more carbon atoms. Unit structure (B) is a unit structure derived, for example, from an aldehyde compound or an aldehyde equivalent. Unit structure (B) is one or more unit structures that include a linked carbon atom [see (I-1) above] bonded to the benzene ring in unit structure (A), and includes, for example, structures represented by formulas (B1), (B2), or (B3) shown below. Unit structure (B) can link two unit structures (A) by covalent bonding with unit structure (A). Unit structure (B) will be described below.

[0085] <<<B-2: Formula (B1)>>> Unit structure (B) includes, for example, a structure represented by the following formula (B1). Unit structure (B-I) may also be a structure represented by the following formula (B1). In formula (B1), R and R' each independently represent a hydrogen atom, an aromatic ring having 6 to 30 carbon atoms which may have substituents other than hydroxyl groups, a heterocycle having 3 to 30 carbon atoms which may have substituents other than hydroxyl groups, or a linear, branched, or cyclic alkyl group having 10 or fewer carbon atoms which may have substituents other than hydroxyl groups. R and R' may together with the carbon atoms they are bonded to to form a structure having a ring structure. * represents a bond. The central carbon atom in formula (B1) is the carbon atom bonded to the carbon atom constituting the benzene ring of the unit structure (A).

[0086] Examples of substituents include halo groups (halogen atoms), alkyl groups, alkenyl groups, alkynyl groups, alkoxy groups, aryl groups, aryloxy groups, formyl groups, cyano groups, nitro groups, tertiary amino groups, ester groups, sulfide-containing groups, and ether-bond-containing groups.

[0087] Furthermore, the two bonds in formula (B1) can each be covalently bonded to the respective benzene rings in the two unit structures (A).

[0088] In the definitions of R and R' in formula (B1), refer to (I-3) and (I-4) above for "aromatic ring" and "heterocyclic ring."

[0089] In the definitions of R and R' in formula (B1), "alkyl group" refers to R in formulas (1a) and (1b) described above. １ Examples of groups similar to the alkyl groups described earlier include those mentioned above.

[0090] Preferably, R and R' are each independently a hydrogen atom, a phenyl, a naphthalenyl, a biphenyl, or a diphenyl ether residue. More preferably, R is a hydrogen atom and R' is a phenyl, biphenyl, or diphenyl ether residue.

[0091] Examples of structures having a ring structure formed by R and R' together with the carbon atoms to which they are bonded include the structure represented by the following formula. (In the formula, each Ar independently represents a residue of an aromatic ring. The carbon atoms indicated by * are the carbon atoms bonded to R and R' in formula (B1).)

[0092] Examples of Ar aromatic rings include the aromatic ring represented by formula (G1).

[0093] The unit structure (B) containing the structure represented by formula (B1) is derived, for example, from an aldehyde compound or a ketone compound. Examples of aldehyde compounds include the compound represented by the following formula (B-1a). Examples of ketone compounds include the compound represented by the following formula (B-1b). (In formulas (B-1a) and (B-1b), R and R' are equivalent to R and R' in formula (B1), respectively, except that R is an atom other than a hydrogen atom. In formula (B-1b), R and R' may, together with the carbon atom to which they are bonded, form a ring structure.)

[0094] For example, when obtaining resin (G), the carbonyl groups in formulas (B-1a) and (B-1b) are converted to *-C-* in formula (B1).

[0095] A few specific examples of unit structures (B) that include the structure represented by formula (B1) are given below. * basically indicates the bonding site with unit structure (A). Needless to say, it is also acceptable for the example structure to be included as part of the whole.

[0096] Although some examples include those with more than two bonding sites (*), these surplus bonding sites can be used for bonding to aromatic rings in other polymer chains, crosslinking, etc.

[0097]

[0098] <<<B-3: Formula (B2)>>> The unit structure (B) in the resin (G) includes, for example, a structure represented by the following formula (B2). The unit structure (B) may also be a structure represented by the following formula (B2).

[0099] In formula (B2), Z ０ This represents an aromatic ring residue, an aliphatic ring residue, or an organic group consisting of two or more aromatic or aliphatic rings linked by a single bond, which may have substituents and have 6 to 30 carbon atoms. Examples of organic groups consisting of two or more aromatic or aliphatic rings linked by a single bond include divalent residues such as biphenyl, cyclohexylphenyl, and bicyclohexyl.

[0100] Examples of substituents include halo groups (halogen atoms), alkyl groups, alkenyl groups, alkynyl groups, alkoxy groups, aryl groups, aryloxy groups, formyl groups, cyano groups, nitro groups, tertiary amino groups, ester groups, sulfide-containing groups, and ether-bond-containing groups.

[0101] J １ and J ２ Each of these independently represents a divalent organic group which may have direct bonds or substituents. Preferably, the divalent organic group is a linear or branched alkylene group having 1 to 6 carbon atoms which may be substituted with an aryl group (phenyl group, substituted phenyl group, etc.) or a halo group (e.g., fluorine). Examples of linear alkylene groups include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, and a hexylene group.

[0102] The unit structure (B) containing the structure represented by formula (B2) is derived, for example, from compounds having a hydroxyl group or alkoxy group bonded to a secondary or tertiary carbon atom, compounds having a hydroxyl group, alkoxy group, or halo group bonded to the α-carbon (benzyl carbon atom, etc.) of an alkylaryl group, or compounds having two carbon-carbon double bonds. These compounds are aldehyde equivalents.

[0103] Examples of compounds having a hydroxyl group or alkoxy group bonded to a secondary or tertiary carbon atom include the compound represented by the following formula (B-2a). Examples of compounds having a hydroxyl group, alkoxy group, or halo group bonded to the α-carbon atom (benzyl carbon atom, etc.) of an alkylaryl group include the compound represented by the following formula (B-2b). Examples of compounds having two carbon-carbon double bonds include the compound represented by the following formula (B-2c) or (B-2d). (In formula (B-2a), formula (B-2b), and formula (B-2b), J １ J ２ , and Z ０ J in equation (B2) １ J ２ , and Z ０ These are synonymous. In equation (B-2a), X ａ , and X ｂ Each of these independently represents a hydroxyl group or an alkoxy group bonded to a secondary or tertiary carbon atom. In formula (B-2b), Y ａ , and Y ｂ Each of these independently represents a hydroxyl group, alkoxy group, or halo group bonded to the α-carbon (benzyl carbon atom, etc.) of the alkylaryl group. In formula (B-2d), n represents an integer from 0 to 4.

[0104] For example, when obtaining resin (G), X in formula (B-2a) ａ -J １ However, in formula (B2) *-J １ It is converted to J. ２ -X ｂ However, J in formula (B2) ２ -* is converted to For example, when obtaining resin (G), Y in formula (B-2b) ａ -J １ However, in formula (B2) *-J １ It is converted to J. ２ -Y ｂ However, J in formula (B2) ２ -It will be converted to *.

[0105] An example of formula (B-2a) is the following compound.

[0106] An example of formula (B-2b) is the following compound.

[0107] An example of formula (B-2c) is the following compound.

[0108] A few specific examples of unit structures containing the structure represented by formula (B2) are given below. * indicates the bonding site with unit structure (A). Needless to say, any unit structure may include the example structure as part of the whole.

[0109]

[0110] <<<B-5: Formula (B3)>>> The unit structure (B) includes, for example, the structure represented by the following formula (B3). The unit structure (B) may also be the structure represented by the following formula (B3). In formula (B3), Z is a monocyclic or dicyclic, tricyclic, or tetracyclic fused ring having 4 to 25 carbon atoms, which may have substituents. The number of carbon atoms referred to herein means only the number of carbon atoms constituting the ring skeleton of the monocyclic or dicyclic, tricyclic, or tetracyclic fused ring, excluding substituents, and does not include the number of heteroatoms constituting the heterocyclic ring if the monocyclic or fused ring is a heterocyclic ring.

[0111] The monoring described above is a monoring whose number of π electrons does not satisfy 4n+2 (where n is a non-negative integer) (hereinafter sometimes referred to as a "non-Hückel monoring"); at least one of the monorings constituting the diring, triring, and tetraring described above is a monoring whose number of π electrons does not satisfy 4n+2 (where n is a non-negative integer), and the remaining monorings may be monorings whose number of π electrons satisfies 4n+2 (where n is a non-negative integer) or monorings whose number of π electrons does not satisfy 4n+2 (where n is a non-negative integer).

[0112] The monocyclic, or bicyclic, tricyclic, or tetracyclic fused ring, may further form fused rings with one or more aromatic rings to form a quintuple or higher fused ring, wherein the number of carbon atoms in the quintuple or higher fused ring is preferably 40 or less. The number of carbon atoms referred to herein means only the number of carbon atoms constituting the ring skeleton of the quintuple or higher fused ring, excluding substituents, and does not include the number of heteroatoms constituting the heterocycle when the quintuple or higher fused ring is a heterocycle.

[0113] X and Y are the same or different, -CR ３１ R ３２ - Represents the base, R ３１ and R ３２ Each of these terms may be the same or different, representing a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms.

[0114] x and y represent the numbers X and Y, respectively, and each can independently represent either 0 or 1.

[0115] In formula (B3) And in formula (B3) At least one of these is bonded to any of the carbon atoms constituting the non-Hückel monoring of Z (referred to as "carbon Z") (when x=1, y=1) or extends from carbon Z (when x=0, y=0).

[0116] For example, in formula (B3) It is bonded to any of the carbon atoms constituting the non-Hückel monoring of Z (referred to as "carbon atom 1") (when x=1) or extends from carbon atom 1 (when x=0),

[0117] In formula (B3) It is bonded to any of the carbon atoms constituting the non-Hückel monoring of Z (referred to as "carbon atom 2") (when y=1) or extends from carbon atom 2 (when y=0), and carbon atom 1 and carbon atom 2 may be the same or different. If they are different, they may belong to the same non-Hückel monoring or to different non-Hückel monorings.

[0118] Furthermore, formula (B3) may optionally include linked carbon atoms other than carbon atoms 1 and 2. Note that if Z is a tricyclic or multicyclic fused ring, the permutational positional relationship between carbon atoms 1 and 2 in formula (B3) and one or two non-Hückel monorings to which they belong and the remaining monoring is arbitrary. Similarly, if carbon atoms 1 and 2 belong to different non-Hückel monorings (referred to as "non-Hückel monoring 1" and "non-Hückel monoring 2," respectively), the permutational positional relationship between non-Hückel monoring 1 and non-Hückel monoring 2 in the fused ring is also arbitrary. Some specific examples of organic groups containing the structure represented by formula (B3) are given below. The bonding site to the unit structure (A) is not particularly limited. Needless to say, the structure may include the example structure as part of the whole.

[0119] Although some examples include those with more than two bonding sites (*), these surplus bonding sites can be used for bonding to aromatic rings in other polymer chains, crosslinking, etc.

[0120]

[0121]

[0122]

[0123]

[0124]

[0125]

[0126] In formula (B3) below, And in formula (B3) We will now describe the case where only one of the atoms is bonded to any of the carbon atoms constituting the non-Hückel monoring of Z (referred to as "carbon atom Z") (when x=1, y=1) or extends from carbon atom Z (when x=0, y=0). As a more specific structure of equation (B3) in this case, for example, in the following equation (C31), p and k can be bonding hands. １ and k ２ Of these, p and k １ , or p and k ２This can result in the unit structure (B) represented by formula (B3). The remaining bonds are connected to hydrogen atoms.

[0127] Furthermore, in the following equation (C32), p and k can be bonding points. １ , k ２ And of m, p and k １ p and k ２ Alternatively, p and m can form a unit structure (B) represented by formula (B3). The remaining bonds are bonded to hydrogen atoms.

[0128] A few more specific examples of formula (B3) corresponding to formula (C31) or formula (C32) are given below. * indicates the bonding site with the unit structure (A).

[0129] In equation (B3), bonds extend from the aromatic rings in these structures to other unit structures (for example, unit structure (A)), but these bonds are omitted in the specific examples below. Needless to say, any unit structure may include the example structure as part of the whole. Furthermore, in the above specific example, if there are no bonds from the aromatic ring, it can be considered a specific example of a polymer end.

[0130] Novolac resins having the structure represented by formula (AB) can be prepared by known methods. For example, ring-containing compounds represented by H-A-H and OHC-B, O=C-B, RO-B-OR, RO-CH ２ -B-CH ２ It can be prepared by condensing oxygen-containing compounds represented by -OR, etc. Here, A and B are the same as above. R represents a hydrogen atom, a halogen, or an alkyl group having about 1 to 3 carbon atoms.

[0131] The ring-containing compound and the oxygen-containing compound may be used individually, or two or more may be used in combination. In this condensation reaction, the oxygen-containing compound can be used in a ratio of 0.1 to 10 moles, preferably 0.1 to 2 moles, per mole of the ring-containing compound.

[0132] Examples of catalysts used in the condensation reaction include mineral acids such as sulfuric acid, phosphoric acid, and perchloric acid; organic sulfonic acids such as p-toluenesulfonic acid, p-toluenesulfonic acid monohydrate, methanesulfonic acid, and trifluoromethanesulfonic acid; and carboxylic acids such as formic acid and oxalic acid. The amount of catalyst used varies depending on the type of catalyst used, but is usually 0.001 to 10,000 parts by mass, preferably 0.01 to 1,000 parts by mass, and more preferably 0.05 to 100 parts by mass, per 100 parts by mass of the cyclic compound (total of multiple types).

[0133] The condensation reaction can be carried out without a solvent, but it is usually carried out using a solvent. The solvent is not particularly limited as long as it can dissolve the reaction substrate and does not inhibit the reaction. Examples include 1,2-dimethoxyethane, diethylene glycol dimethyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, tetrahydrofuran, tetrahydropyran, dioxane, 1,2-dichloromethane, 1,2-dichloroethane, toluene, N-methylpyrrolidone, and dimethylformamide. The condensation reaction temperature is usually 40°C to 200°C, preferably 100°C to 180°C. The reaction time varies depending on the reaction temperature, but is usually 5 minutes to 50 hours, preferably 5 minutes to 24 hours.

[0134] The weight-average molecular weight of the novolac resin according to one aspect of the present invention is typically 500 to 100,000, preferably 600 to 50,000, 700 to 10,000, or 800 to 8,000.

[0135] The resin (G) content in the resist underlayer film forming composition is preferably 25 to 100% by mass, more preferably 50 to 100% by mass, and even more preferably 70 to 100% by mass, relative to the mass of the film-forming component. Here, the film-forming component refers to the component obtained by removing the solvent component from the resist underlayer film forming composition.

[0136] The molar ratio of unit structure (A) to unit structure (B) in resin (G) is preferably, for example, 30:70 to 50:50, more preferably 40:60 to 50:50, and even more preferably 50:55 to 50:50. Furthermore, the molar ratio of unit structure (A) to unit structure (B) in resin (G) can also be expressed as the molar ratio of compound (A), which is the raw material for unit structure (A), to compound (B), which is the raw material for unit structure (B). The molar ratio of compound (A) to compound (B) is preferably, for example, 30:70 to 50:50, more preferably 40:60 to 50:50, and even more preferably 50:55 to 50:50. Here, compound (A) may be one type or two or more types. Similarly, compound (B) may be one type or two or more types.

[0137] The resin (G) is preferably a resin synthesized by polymerizing at least one compound having a biphenyl skeleton or biphenyl analog structure with at least one aromatic ketone or aliphatic ketone in the presence of an acid catalyst. Examples of aromatic ketones or aliphatic ketones include the ketone compounds described in (B-2) above. Examples of acid catalysts include at least one selected from the group consisting of acids and their salts, and acid generators, which will be described later.

[0138] <Solvent> A composition for forming a resist underlayer film, which is one aspect of the present invention, contains a solvent.

[0139] The solvent is not particularly limited as long as it can dissolve the specific novolac resin and any other optional components that may be added as needed.

[0140] Examples of solvents include methyl cellosolve acetate, ethyl cellosolve acetate, propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, methyl isobutyl carbinol, propylene glycol monobutyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, and Luene, xylene, methyl ethyl ketone, cyclopentanone, cyclohexanone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyethyl acetate, ethyl hydroxyethyl acetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol Monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol dipropyl ether, propylene glycol dibutyl ether, ethyl lactate, propyl lactate, isopropyl lactate, butyl lactate, isobutyl lactate, methyl formate, ethyl formate, propyl formate, isopropyl formate, butyl formate, isobutyl formate, amyl formate, isoamyl formate, methyl acetate, ethyl acetate, amyl acetate, isoamyl acetate, hexyl acetate, methyl propionate, ethyl propionate, propyl propionate,Examples of solvents include isopropyl propionate, butyl propionate, isobutyl propionate, methyl butyrate, ethyl butyrate, propyl butyrate, isopropyl butyrate, butyl butyrate, isobutyl butyrate, methyl 2-hydroxy-2-methylpropionate, methyl 3-methoxy-2-methylpropionate, methyl 2-hydroxy-3-methylbutyrate, ethyl methoxyethyl, 3-methoxybutyl acetate, 3-methoxypropyl acetate, 3-methyl-3-methoxybutyl acetate, 3-methyl-3-methoxybutyl propionate, 3-methyl-3-methoxybutyl butyrate, methyl acetoacetate, methyl propyl ketone, methyl butyl ketone, 2-heptanone, 3-heptanone, 4-heptanone, N,N-dimethylformamide, N-methylacetamide, N,N-dimethylacetamide, N-methylpyrrolidone, 4-methyl-2-pentanol, and γ-butyrolactone. These solvents can be used individually or in combination of two or more. Furthermore, the boiling point of the solvent that can be used is preferably 140°C or higher, more preferably 160°C or higher, but is not particularly limited.

[0141] Furthermore, solvents with a boiling point of 160°C or higher can be included in combination with solvents with a boiling point of less than 160°C.

[0142] As such high-boiling point solvents, for example, the following compounds described in International Publication No. 2018 / 131562 (A1) can be preferably used.

[0143] [R in equation (i)] １ , R ２ and R ３ Each represents a hydrogen atom, an oxygen atom, a sulfur atom, or an alkyl group having 1 to 20 carbon atoms, which may be interrupted by an amide bond. These atoms may be the same or different, and may be bonded to each other to form a ring structure. Alternatively, 1,6-diacetoxyhexane (boiling point 260°C), tripropylene glycol monomethyl ether (boiling point 242°C), and various other high-boiling point solvents described in paragraph 0082 of Japanese Patent Publication No. 2021-84974 can be preferably used.

[0144] Alternatively, as described in Japanese Patent Publication No. 2019-20701, dipropylene glycol monomethyl ether acetate (boiling point 213°C), diethylene glycol monoethyl ether acetate (boiling point 217°C), diethylene glycol monobutyl ether acetate (boiling point 247°C), dipropylene glycol dimethyl ether (boiling point 171°C), dipropylene glycol monomethyl ether (boiling point 187°C), dipropylene glycol monobutyl ether (boiling point 231°C), tripropylene glycol mo Various high-boiling point solvents described in paragraphs 0023 to 0031 of the published patent can be preferably used, including methyl ether (boiling point 242°C), γ-butyrolactone (boiling point 204°C), benzyl alcohol (boiling point 205°C), propylene carbonate (boiling point 242°C), tetraethylene glycol dimethyl ether (boiling point 275°C), 1,6-diacetoxyhexane (boiling point 260°C), dipropylene glycol (boiling point 230°C), 1,3-butylene glycol diacetate (boiling point 232°C), and others.

[0145] A composition for forming a resist underlayer film, according to one aspect of the present invention, may contain an acid and / or a salt thereof and / or an acid generator.

[0146] Examples of acids include p-toluenesulfonic acid, trifluoromethanesulfonic acid, salicylic acid, 5-sulfosalicylic acid, 4-phenolsulfonic acid, camphorsulfonic acid, 4-chlorobenzenesulfonic acid, benzenedisulfonic acid, 1-naphthalenesulfonic acid, citric acid, benzoic acid, hydroxybenzoic acid, and naphthalenecarboxylic acid.

[0147] As the salt, the aforementioned acid salts can also be used. While not limited to these, ammonia derivative salts such as trimethylamine salt and triethylamine salt, pyridine derivative salts, and morpholine derivative salts can be suitably used.

[0148] Only one type of acid and / or its salt may be used, or two or more types may be used in combination. The amount added is usually 0.0001 to 20% by mass, preferably 0.0005 to 10% by mass, and more preferably 0.01 to 5% by mass, relative to the total solids.

[0149] Examples of acid generators include thermal acid generators and photoacid generators.

[0150] Examples of thermal acid generators include 2,4,4,6-tetrabromocyclohexadienone, benzoin tosylate, 2-nitrobenzyl tosylate, K-PURE® CXC-1612, CXC-1614, TAG-2172, TAG-2179, TAG-2678, TAG2689, TAG2700 (manufactured by King Industries), and SI-45, SI-60, SI-80, SI-100, SI-110, SI-150 (manufactured by Sanshin Chemical Industry Co., Ltd.), and other alkyl organic sulfonates.

[0151] The photoacid generator produces acid when the resist is exposed to light. Therefore, the acidity of the underlying film can be adjusted. This is one method for matching the acidity of the underlying film to that of the upper resist. Furthermore, adjusting the acidity of the underlying film allows for adjustment of the pattern shape of the resist formed on the upper layer.

[0152] Examples of photoacid generators included in the resist underlayer film forming composition of the present invention include onium salt compounds, sulfonimide compounds, and disulfonyl diazomethane compounds.

[0153] Examples of iodonium salt compounds include iodonium salt compounds such as diphenyliodonium hexafluorophosphate, diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoron-butanesulfonate, diphenyliodonium perfluoron-octanesulfonate, diphenyliodonium camphorsulfonate, bis(4-tert-butylphenyl)iodonium camphorsulfonate and bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate, and sulfonium salt compounds such as triphenylsulfonium hexafluoroantimonate, triphenylsulfonium nonafluoron-butanesulfonate, triphenylsulfonium camphorsulfonate and triphenylsulfonium trifluoromethanesulfonate.

[0154] Examples of sulfonimide compounds include N-(trifluoromethanesulfonyloxy)succinimide, N-(nonafluoron-butanesulfonyloxy)succinimide, N-(camphorsulfonyloxy)succinimide, and N-(trifluoromethanesulfonyloxy)naphthalimide.

[0155] Examples of disulfonyl diazomethane compounds include bis(trifluoromethylsulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, bis(phenylsulfonyl)diazomethane, bis(p-toluenesulfonyl)diazomethane, bis(2,4-dimethylbenzenesulfonyl)diazomethane, and methylsulfonyl-p-toluenesulfonyldiazomethane.

[0156] Only one type of acid generator may be used, or two or more types may be used in combination.

[0157] If an acid generator is used, the ratio is 0.01 to 10 parts by mass, or 0.1 to 8 parts by mass, or 0.5 to 5 parts by mass, per 100 parts by mass of solid content of the resist underlayer film forming composition.

[0158] A resist underlayer film forming composition according to one aspect of the present invention may optionally contain, in addition to the above, a crosslinking agent, a surfactant, a photoabsorbent, a rheology modifier, an adhesion aid, and the like.

[0159] Typical crosslinking agents include aminoplast crosslinking agents and phenoplast crosslinking agents.

[0160] As the crosslinking agent, a crosslinking agent with high heat resistance can be used. Preferably, a crosslinking agent with high heat resistance is a compound containing a crosslinking substituent having an aromatic ring (e.g., a benzene ring, a naphthalene ring) in its molecule.

[0161] Examples of aminoplast crosslinking agents include highly alkylated, alkoxylated, or alkoxyalkylated melamine, benzoguanamine, glycoluryl, urea, and polymers thereof. Preferably, the crosslinking agent has at least two crosslinking substituents and is a compound such as methoxymethylated glycoluryl, butoxymethylated glycoluryl, methoxymethylated melamine, butoxymethylated melamine, methoxymethylated benzoguanamine, butoxymethylated benzoguanamine, methoxymethylated urea, butoxymethylated urea, methoxymethylated thiourea, or methoxymethylated thiourea. Condensed products of these compounds can also be used.

[0162] Preferably, it is at least one selected from the group consisting of tetramethoxymethylglycoluryl and hexamethoxymethylmelamine.

[0163] Here are a few specific examples:

[0164]

[0165] Examples of phenoplast crosslinking agents include highly alkylated, alkoxylated, or alkoxyalkylated aromatics and polymers thereof. Preferably, the crosslinking agent has at least two crosslinking substituents in one molecule, and is a compound such as 2,6-dihydroxymethyl-4-methylphenol, 2,4-dihydroxymethyl-6-methylphenol, bis(2-hydroxy-3-hydroxymethyl-5-methylphenyl)methane, bis(4-hydroxy-3-hydroxymethyl-5-methylphenyl)methane, 2,2-bis(4-hydroxy-3,5-dihydroxymethylphenyl)propane, bis(3-formyl-4-hydroxyphenyl)methane, bis(4-hydroxy-2,5-dimethylphenyl)formylmethane, or α,α-bis(4-hydroxy-2,5-dimethylphenyl)-4-formyltoluene. Condensates of these compounds can also be used.

[0166] Examples of such compounds include compounds having the substructure of formula (4) below, and polymers or oligomers having the repeating unit of formula (5) below.

[0167] The above R １１ , R １２ , R １３ , and R １４ n1 is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and the alkyl groups described above can be used. n1 is an integer from 1 to 4, n2 is an integer from 1 to (5-n1), and (n1+n2) is an integer from 2 to 5. n3 is an integer from 1 to 4, n4 is from 0 to (4-n3), and (n3+n4) is an integer from 1 to 4. The oligomers and polymers can be used with a number of repeating unit structures ranging from 2 to 100, or from 2 to 50.

[0168] Here are a few specific examples:

[0169]

[0170]

[0171]

[0172]

[0173] Crosslinking agents such as aminoplast crosslinking agents and phenoplast crosslinking agents may be used individually or in combination of two or more. Aminoplast crosslinking agents can be manufactured by known methods or similar methods, or commercially available products may be used.

[0174] Furthermore, the amount of crosslinking agent used, such as aminoplast crosslinking agent or phenoplast crosslinking agent, varies depending on the coating solvent used, the substrate used, the required solution viscosity, the required film shape, etc., but is 0.001% by mass or more, 0.01% by mass or more, 0.05% by mass or more, 0.5% by mass or more, or 1.0% by mass or more, relative to the total solid content of the resist underlayer film forming composition according to the present invention, and is 80% by mass or less, 50% by mass or less, 40% by mass or less, 20% by mass or less, or 10% by mass or less.

[0175] The resist underlayer film forming composition according to the present invention does not produce pinholes or striations, and a surfactant may be added to further improve the coatability against surface unevenness.

[0176] Examples of surfactants include nonionic surfactants such as: polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, and polyoxyethylene oleyl ether; polyoxyethylene alkylaryl ethers such as polyoxyethylene octyl phenol ether and polyoxyethylene nonyl phenol ether; polyoxyethylene-polyoxypropylene block copolymers; sorbitan fatty acid esters such as sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, and sorbitan tristearate; and polyoxyethylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, and polyoxyethylene sorbitan tristearate. Examples include fluorine-based surfactants such as Eftop EF301, EF303, EF352 (manufactured by Tochem Products Co., Ltd., product names), Megafac F171, F173, R-30, R-40 (manufactured by Dainippon Ink, Inc., product names), Florard FC430, FC431 (manufactured by Sumitomo 3M Limited, product names), Asahiguard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by Asahi Glass Co., Ltd., product names), and organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.).

[0177] The amount of these surfactants added is usually 2.0% by mass or less, preferably 1.0% by mass or less, relative to the total solid content of the resist underlayer film forming composition according to the present invention. These surfactants may be added individually or in combination of two or more types.

[0178] Examples of light absorbers include commercially available light absorbers listed in "Technology and Market of Industrial Dyes" (CMC Publishing) and "Dye Handbook" (edited by the Society of Synthetic Organic Chemistry), such as C.I. Disperse Yellow 1, 3, 4, 5, 7, 8, 13, 23, 31, 49, 50, 51, 54, 60, 64, 66, 68, 79, 82, 88, 90, 93, 102, 114 and 124; C.I. Disperse Orange 1, 5, 13, 25, 29, 30, 31, 44, 57, 72 and 73; C.I. DisperseRed 1, 5, 7, 13, 17, 19, 43, 50, 54, 58, 65, 72, 73, 88, 117, 137, 143, 199 and 210; C. I. DisperseViolet 43; C. I. DisperseBlue 96; C. I. Fluorescent Brightening Agent 112, 135 and 163; C. I. SolventOrange 2 and 45; C. I. SolventRed 1, 3, 8, 23, 24, 25, 27 and 49; C. I. PigmentGreen 10; C. I. Pigment Brown 2 and others can be suitably used. The above light absorber is usually blended in a proportion of 10% by mass or less, preferably 5% by mass or less, relative to the total solid content of the resist underlayer film forming composition according to the present invention.

[0179] Rheology modifiers are added primarily to improve the fluidity of the resist underlayer film formation composition, and particularly in the baking process, to improve the uniformity of the resist underlayer film thickness and the filling of holes by the resist underlayer film formation composition. Specific examples include phthalate derivatives such as dimethyl phthalate, diethyl phthalate, diisobutyl phthalate, dihexyl phthalate, and butyl isodecyl phthalate; adipic acid derivatives such as dinormal butyl adipate, diisobutyl adipate, diisooctyl adipate, and octyldecyl adipate; maleic acid derivatives such as di(n-butyl) malate, diethyl malate, and dinonyl malate; oleic acid derivatives such as methyl oleate, butyl oleate, and tetrahydrofurfuryl oleate; or stearic acid derivatives such as n-butyl stearate and glyceryl stearate. These rheology modifiers are typically blended in a proportion of less than 30% by mass relative to the total solid content of the resist underlayer film formation composition according to the present invention.

[0180] Adhesion aids are added primarily to improve the adhesion between the substrate or resist and the resist underlayer film forming composition, and especially to prevent the resist from peeling off during development. Specific examples include chlorosilanes such as trimethylchlorosilane, dimethylvinylchlorosilane, methyldiphenylchlorosilane, and chloromethyldimethylchlorosilane; alkoxysilanes such as trimethylmethoxysilane, dimethyldiethoxysilane, methyldimethoxysilane, dimethylvinylethoxysilane, diphenyldimethoxysilane, and phenyltriethoxysilane; silazanes such as hexamethyldisilazane, N,N'-bis(trimethylsilyl)urea, dimethyltrimethylsilylamine, and trimethylsilylimidazole; and vinyltrichlorosilane. Examples of adhesive aids include silanes such as ran, γ-chloropropyltrimethoxysilane, γ-aminopropyltriethoxysilane, and γ-glycidoxypropyltrimethoxysilane; heterocyclic compounds such as benzotriazole, benzimidazole, indazole, imidazole, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, urazole, thiouracil, mercaptoimidazole, and mercaptopyrimidine; and ureas such as 1,1-dimethylurea and 1,3-dimethylurea, or thiourea compounds. These adhesive aids are typically blended in a proportion of less than 5% by mass, preferably less than 2% by mass, relative to the total solid content of the resist underlayer film forming composition according to the present invention.

[0181] The solid content of the resist underlayer film forming composition according to the present invention is 0.1 to 70% by mass, or 0.1 to 60% by mass. The solid content is the proportion of all components in the resist underlayer film forming composition excluding the solvent. The solid content may contain a crosslinkable resin in a proportion of 1 to 99.9% by mass, or 50 to 99.9% by mass, or 50 to 95% by mass, or 50 to 90% by mass.

[0182] [Resist Underlayer Film] The resist underlayer film of the present invention is a cured product of the resist underlayer film forming composition of the present invention. The resist underlayer film can be formed using the resist underlayer film forming composition of the present invention, for example, as follows.

[0183] Substrates used in the manufacture of semiconductor devices (e.g., silicon wafer substrates, silicon dioxide coated substrates (SiO ２ A resist underlayer film forming composition according to one embodiment of the present invention is applied to a substrate (such as a glass substrate, silicon nitride substrate (SiN substrate), silicon oxide nitride substrate (SiON substrate), titanium nitride substrate (TiN substrate), tungsten substrate (W substrate), glass substrate, ITO substrate, polyimide substrate, and low dielectric constant material (low-k material) coated substrate, etc.) using an appropriate coating method such as a spinner or coater, and then fired using a heating means such as a hot plate to form a resist underlayer film. The firing conditions are appropriately selected from a firing temperature of 80°C to 800°C and a firing time of 0.3 to 60 minutes. Preferably, the firing temperature is 150°C to 500°C and the firing time is 0.5 to 2 minutes. Air may be used as the atmospheric gas during firing, or an inert gas such as nitrogen or argon may be used. In one embodiment, it is particularly preferable that the oxygen concentration is 1% or less. The thickness of the underlying film formed here can be, for example, 10 to 1000 nm, 20 to 500 nm, 30 to 400 nm, or 50 to 300 nm. Furthermore, if a quartz substrate is used as the substrate, a replica (mold replica) of the quartz imprint mold can be fabricated.

[0184] Furthermore, according to one aspect of the present invention, an adhesion layer and / or a silicon-containing layer containing 99% by mass or less, or 50% by mass or less, of Si can be formed on the resist underlayer film by coating or vapor deposition. For example, in addition to the method of forming the adhesion layer described in Japanese Patent Application Publication No. 2013-202982 and Japanese Patent No. 5827180, or the silicon-containing resist underlayer film (inorganic resist underlayer film) formation composition described in International Publication No. 2009 / 104552 (A1) by spin coating, a Si-based inorganic material film can be formed by CVD or the like.

[0185] Furthermore, by applying a resist underlayer film forming composition, which is one aspect of the present invention, to a semiconductor substrate having stepped portions and portions without steps (a so-called stepped substrate) and firing it, the step difference between the stepped portions and the portions without steps can be reduced.

[0186] [Method for forming a resist pattern] The method for forming a resist pattern of the present invention includes at least the step of applying 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 forming a resist pattern of the present invention may also include the following steps: - A step of forming a resist film on the resist underlayer film. - A step of irradiating the resist film with light or an electron beam, then developing the resist film to obtain a resist pattern. and - A step of etching the resist underlayer film using the resist pattern as a mask.

[0187] [Method for Manufacturing a Semiconductor Device] (i) A method for manufacturing a semiconductor device according to one aspect of the present invention includes the steps of: forming a resist underlayer film on a semiconductor substrate using a resist underlayer film forming composition according to one aspect of the present invention; forming a resist film on the resist underlayer film; forming a resist pattern by irradiating the resist film with light or an electron beam and developing it; etching the resist underlayer film through the resist pattern to form a patterned resist underlayer film; and processing the semiconductor substrate through the patterned resist underlayer film.

[0188] (ii) A method for manufacturing a semiconductor device according to one aspect of the present invention includes the steps of: forming a resist underlayer film on a semiconductor substrate using a resist underlayer film forming composition according to one aspect of the present invention; forming a hard mask on the resist underlayer film; further forming a resist film on the hard mask; forming a resist pattern by irradiating the resist film with light or an electron beam and developing it; etching the hard mask through the resist pattern to form a patterned hard mask; etching the resist underlayer film through the patterned hard mask to form a patterned resist underlayer film; and processing the semiconductor substrate through the patterned resist underlayer film.

[0189] (iii) Furthermore, a method for manufacturing a semiconductor device according to one aspect of the present invention includes the steps of: forming a resist underlayer film on a semiconductor substrate using a resist underlayer film forming composition according to one aspect of the present invention; forming a hard mask on the resist underlayer film; further forming a resist film on the hard mask; forming a resist pattern by irradiating the resist film with light or an electron beam and developing it; etching the hard mask through the resist pattern to form a patterned hard mask; etching the resist underlayer film through the patterned hard mask to form a patterned resist underlayer film; removing the hard mask; and processing the semiconductor substrate through the patterned resist underlayer film.

[0190] (iv) A method for manufacturing a semiconductor device according to one aspect of the present invention includes the steps of: forming a resist underlayer film on a semiconductor substrate using a resist underlayer film forming composition according to one aspect of the present invention; forming a hard mask on the resist underlayer film; further forming a resist film on the hard mask; forming a resist pattern by irradiating the resist film with light or an electron beam and developing it; etching the hard mask through the resist pattern to form a patterned hard mask; etching the resist underlayer film through the patterned hard mask to form a patterned resist underlayer film; removing the hard mask; forming a vapor-deposited film (spacer) on the resist underlayer film after the hard mask has been removed; processing the vapor-deposited film (spacer) by etching; removing the patterned resist underlayer film and leaving the patterned vapor-deposited film (spacer); and processing the semiconductor substrate through the patterned vapor-deposited film (spacer).

[0191] The semiconductor substrate can be processed using the manufacturing methods described in (i) to (iv) above.

[0192] The step of forming a resist underlayer film using a resist underlayer film formation composition according to one aspect of the present invention is as described above in [Resist Underlayer Film].

[0193] A hard mask, such as a silicon-containing film, may be formed as a second resist underlayer on the resist underlayer formed by the above process, and a resist pattern may be formed thereon [as described in (ii) to (iv)].

[0194] The hard mask may be a coated film of inorganic material, or a vapor-deposited film of inorganic material formed by vapor deposition methods such as CVD or PVD, or a SiO film, SiN film, or SiO ２ A membrane can be used as an example.

[0195] Furthermore, an anti-reflective coating (BARC) may be formed on this hard mask, or a resist shape correction film that does not have anti-reflective properties may be formed.

[0196] In the process of forming the resist pattern, exposure is performed either through a mask (reticle) for forming a predetermined pattern or by direct drawing. For example, g-line, i-line, KrF excimer laser, ArF excimer laser, EUV, and electron beams can be used as exposure sources. After exposure, post-exposure baking is performed as needed. Then, the resist is developed with a developer (e.g., 2.38% by mass aqueous solution of tetramethylammonium hydroxide, butyl acetate), and further rinsed with a rinse solution or pure water to remove the used developer. Finally, post-baking is performed to dry the resist pattern and improve its adhesion to the substrate.

[0197] The etching process performed after the formation of the resist pattern is carried out by dry etching.

[0198] Furthermore, the following gases are used for processing the hard mask (silicon-containing layer), resist underlayer film, and substrate: CF ４ CHF ３ ,CH ２ F ２ CH ３ F, C ４ F ６ , C ４ F ８ , O ２ , N ２ O, NO ２ , H ２He can be used. These gases may be used alone or in mixtures of two or more gases. Furthermore, these gases may be mixed with argon, nitrogen, carbon dioxide, carbonyl sulfide, sulfur dioxide, neon, or nitrogen trifluoride.

[0199] The resist film may be patterned by a nanoimprint method or a self-assembled film method.

[0200] In nanoimprint lithography, the resist composition is formed using a patterned mold that is transparent to irradiated light. In contrast, self-assembled film lithography uses self-assembled films, such as diblock polymers (e.g., polystyrene-polymethyl methacrylate), which naturally form ordered structures on the nanometer scale, to create patterns.

[0201] In the nanoimprint method, before applying the curable composition that will become the resist film, a silicon-containing layer (hard mask layer) may be optionally formed on the resist underlayer by coating or vapor deposition, and an adhesion layer may be further formed on the resist underlayer or the silicon-containing layer (hard mask layer) by coating or vapor deposition, and the curable composition that will become the resist film may be applied on the adhesion layer.

[0202] Furthermore, wet etching may be performed to simplify the process steps and reduce damage to the processed substrate. This helps to suppress variations in processed dimensions and a reduction in pattern roughness, making it possible to process the substrate with a high yield. For this reason, in (iii) to (iv) above, the hard mask can be removed by either etching or an alkaline chemical solution. In particular, when using an alkaline chemical solution, there are no restrictions on the components, but it is preferable that the alkaline components include the following.

[0203] Examples of alkaline components include tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, methyltripropylammonium hydroxide, methyltributylammonium hydroxide, ethyltrimethylammonium hydroxide, dimethyldiethylammonium hydroxide, benzyltrimethylammonium hydroxide, hexadecyltrimethylammonium hydroxide, and (2-hydroxyethyl)trimethylammonium hydroxide, monoethanolamine, diethanolamine, triethanolamine, 2-(2-aminoethoxy)ethanol, N,N-dimethylethanolamine, N,N-diethylethanolamine, N Examples include N-dibutylethanolamine, N-methylethanolamine, N-ethylethanolamine, N-butylethanolamine, N-methyldiethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, tetrahydrofurfurylamine, N-(2-aminoethyl)piperazine, 1,8-diazabicyclo[5.4.0]undecene-7, 1,4-diazabicyclo[2.2.2]octane, hydroxyethylpiperazine, piperazine, 2-methylpiperazine, trans-2,5-dimethylpiperazine, cis-2,6-dimethylpiperazine, 2-piperidinemethanol, cyclohexylamine, 1,5-diazabicyclo[4,3,0]nonene-5, etc. Furthermore, from the viewpoint of handling, tetramethylammonium hydroxide and tetraethylammonium hydroxide are particularly preferred, and an inorganic base may be used in combination with a quaternary ammonium hydroxide. As inorganic bases, alkali metal hydroxides such as potassium hydroxide, sodium hydroxide, and rubidium hydroxide are preferred, with potassium hydroxide being more preferred.

[0204] The present invention will be described more specifically below with reference to synthesis examples, examples, and comparative examples, but the present invention is not limited to the examples described below.

[0205] The weight-average molecular weight Mw of the resins shown in Synthesis Examples 1 to 7 below was 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: GPC column: TSKgel Super-MultiporeHZ-N (2 columns) Column temperature: 40°C Solvent: Tetrahydrofuran (THF) Flow rate: 0.35 ml / min Standard sample: Polystyrene (manufactured by Tosoh Corporation)

[0206] [Synthesis of Resins] For the synthesis of resins with structural formulas (S1) to (S4) as resins to be used as the underlayer film of the resist, and for the synthesis of structural formulas (S'1) to (S'3) as comparative examples, the following compound groups A, B, C, catalyst group D, solvent group E, and reprecipitation solvent group F were used.

[0207] (Compound groups A to C)

[0208] (Catalyst Group D) p-toluenesulfonic acid: D1 3-mercaptopropionic acid: D2 Potassium carbonate: D3

[0209] (Solvent group E) Propylene glycol monomethyl ether acetate (= PGMEA): E1 Acetone: E2

[0210] (Reprecipitation solvent group F) Methanol / water: F1 Methanol: F2

[0211] [Synthesis Example 1] 10.7 g of (A1), 10.4 g of (B1), 10.1 g of (D1), 0.4 g of (D2), and 33.3 g of (E1) were placed in a flask. The mixture was then heated at 120°C under a nitrogen atmosphere and reacted for approximately 48 hours. After the reaction was stopped, the mixture was reprecipitated with (F1) and dried to obtain a resin (S1) with the following structure. The weight-average molecular weight Mw, measured in polystyrene equivalent by GPC, was approximately 3,500. The obtained resin was dissolved in PGMEA, and ion exchange was carried out for 4 hours using a cation exchange resin and an anion exchange resin to obtain a solution of the target compound.

[0212] [Synthesis Examples 2-5] Compound group A, compound group B, catalyst group D, solvent group E, and reprecipitation solvent group F were changed as shown in Table 1 to synthesize resins for use as the resist underlayer film. The experimental procedure was the same as in Synthesis Example 1. The resins were synthesized under the conditions shown in Table 1 to obtain the example resins (S2) to (S4), the comparative example resin (S'1), and their solutions.

[0213]

[0214] The structural formulas of the obtained resins (S1) to (S4) and resin (S'1) are shown below.

[0215]

[0216] [Synthesis Example 6] 10.0 g of the reprecipitated resin (S1) obtained in Synthesis Example 1, 7.99 g of (D3), and 23.5 g of (E2) were placed in a flask. Then, the flask was placed under a nitrogen atmosphere, 5.1 g of (C1) was added, and the mixture was heated under reflux and reacted for approximately 24 hours. After the reaction was stopped, the reaction solution was filtered, the organic layer was concentrated, redissolved in PGMEA, reprecipitated using (F2), and dried to obtain the resin (S'2) shown in the following structure. The weight-average molecular weight Mw, measured in polystyrene equivalent by GPC, was approximately 3,300. The obtained resin was dissolved in PGMEA, and ion exchange was carried out for 4 hours using a cation exchange resin and an anion exchange resin to obtain the target compound solution.

[0217] [Synthesis Example 7] In Synthesis Example 6, resin (S1) was changed to (S'1) 5.6 g, and resin (S'3) and its compound solution were obtained under the same conditions and procedures using (D3) 4.4 g, (E2) 12.9 g, and (C1) 2.7 g. The resin (S'3) and its compound solution were shown in the following structure.

[0218] [Preparation of compositions for forming a resist underlayer film] [Examples 1-4, Comparative Examples 1-3] Each PGMEA solution of resins (S1)-(S4) and (S'1)-(S'3) was diluted with PGMEA and filtered through a 0.1 μm polytetrafluoroethylene microfilter to prepare compositions for forming a resist underlayer film (M1-M4, M'1-M'3).

[0219] [Measurement of Etching Rate] The etching equipment and etching gas used for etching measurement are as follows: RIE-200NL (Samco): CF ４　　 50 sccm

[0220] The resist underlayer film formation compositions of Examples 1-4 and Comparative Examples 1-3 were heated at 400°C for 90 seconds to adjust their concentration so that the film thickness was approximately 100 nm. Each composition was then applied to a silicon wafer using a spin coater and heated again. As the etching gas, CF ４ The dry etching rate was measured using [a specific method]. The dry etching rate ratio was calculated as (difference in thickness of the resist underlayer film before and after etching) / (difference in thickness of the KrF resist before and after etching). Compositions with a ratio less than 0.9 were judged to have etching resistance "○", and compositions with a ratio of 0.9 or higher were judged to have etching resistance "×". The results are shown in Table 2.

[0221] [Embedding Test for Stepped Substrates] As an embedding test for stepped substrates, SiO ２ The substrate was checked to see if the resist underlayer film formation composition filled the stepped substrate with a trench width of 10 nm and a depth of 200 nm. The resist underlayer film formation compositions of Examples 1 to 4 and Comparative Examples 1 to 3 were applied to the substrate and then baked at 400°C for 90 seconds to form a resist underlayer film of approximately 100 nm. The embedding properties of this substrate were observed using a scanning electron microscope (S-4800) manufactured by Hitachi High-Technologies Corporation. If there were no voids up to the bottom of the pattern, it was considered to have good embedding properties and was judged as "○", and if voids were present it was judged as "×". The results are shown in Table 2.

[0222] [Planarization test on stepped substrates] As a planarization test on stepped substrates, SiO ２On a substrate, the coating thickness of a dense pattern area (DENSE) with a trench width of 25 nm, a pitch of 50 nm, and a depth of 100 nm was compared with that of an open area (OPEN) where no pattern was formed. The resist underlayer film formation compositions of Examples 1-4 and Comparative Examples 1-3 were applied to the substrates, and then baked at 400°C for 90 seconds to form a resist underlayer film of approximately 100 nm. The planarity of this substrate was observed using a scanning electron microscope (S-4800) manufactured by Hitachi High-Technologies Corporation, and the planarity was evaluated by measuring the difference in film thickness between the dense area (patterned area) and the open area (unpatterned area) of the stepped substrate (this is the coating step difference between the dense area and the open area, and is called Bias). The evaluation was judged as follows: Bias of less than 15 nm was considered to be the best planarity ("○"), Bias of 15 nm or more and less than 25 nm was "△", and Bias of 25 nm or more was "×". The results are shown in Table 2.

[0223]

[0224] Based on the above, the resin obtained in this invention demonstrated excellent embedding and planarization properties for patterned substrates. Furthermore, it showed sufficient etching resistance to F-based (fluorine-based) gases, which are commonly used etching gases. From these viewpoints, it can be expected to be applied to a wide range of semiconductor devices.

[0225] The present invention provides a resist underlayer film formation composition for use in a multilayer lithography process that is suitable for processes requiring heat resistance of 400°C or higher, exhibits good planarization and embedding properties on a microfabricated substrate, yields an excellent resist pattern, shows sufficient curing characteristics, and also provides an anti-reflective coating effect.

Claims

1. A composition for forming a resist underlayer film, comprising a resin (G) having a composite unit structure and a solvent, wherein the composite unit structure comprises a unit structure (A) having a benzene ring with one hydroxyl group and a unit structure (B) having one or more carbon atoms, the unit structure (A) having a biphenyl skeleton in which the benzene ring and other benzene rings are linked by a single bond, or a biphenyl analog structure in which the benzene ring and other benzene rings are linked via a divalent group, and the resin (G) is a resin obtained by a reaction that generates a covalent bond between the carbon atoms constituting the benzene ring of the unit structure (A) and the carbon atoms in the unit structure (B).

2. The resist lower layer film forming composition according to claim 1, wherein the resin (G) contains any one or two of the composite unit structures represented by the following formula (1a) and the following formula (1b) as the composite unit structure. (In formula (1a) and formula (1b), R １ and R ２ each independently represents an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a halogen atom, and R ３ and R ４ each independently represents a hydrogen atom, an aromatic hydrocarbon group which may have a substituent other than a hydroxy group, or an aliphatic hydrocarbon group which may have a substituent other than a hydroxy group. When R ３ and R ４ bonded to the same carbon atom each represent an aromatic hydrocarbon group which may have a substituent other than a hydroxy group, they may be bonded to each other to form a fluorene ring. When R ３ and R ４ bonded to the same carbon atom each represent an aliphatic hydrocarbon group which may have a substituent other than a hydroxy group, they may be bonded to each other to form an aliphatic hydrocarbon ring. k1 and k2 each independently represent 0 or 1, m1 and m2 each independently represent 0 to 3, (k1 + k2) is 1, and X represents a single bond, -O-, -S-, -COO-, -CO-, -SS-, -SO ２ -, or an alkylene group having 1 to 6 carbon atoms.) 3. The resist underlayer film forming composition according to claim 2, wherein in formula (1a) and formula (1b), the substituents that the aromatic hydrocarbon group and the aliphatic hydrocarbon group may have are one or more groups selected from halogen atoms, alkyl groups, alkenyl groups, alkynyl groups, alkoxy groups, aryl groups, aryloxy groups, formyl groups, cyano groups, nitro groups, tertiary amino groups, ester groups, sulfide-containing groups, and ether-bond-containing groups.

4. The resist underlayer film forming composition according to claim 2, wherein in formula (1a) and formula (1b), the aromatic hydrocarbon group is a phenyl group or a naphthyl group.

5. The resist underlayer film forming composition according to claim 2, wherein in formula (1a) and formula (1b), the aliphatic hydrocarbon group is an alkyl group having 1 to 10 carbon atoms.

6. The resist underlayer film forming composition according to claim 1, wherein the resin (G) is a resin synthesized by polymerizing at least one compound having the biphenyl skeleton or the biphenyl analog structure with at least one aromatic ketone or aliphatic ketone in the presence of an acid catalyst.

7. The resist underlayer film forming composition according to claim 1, wherein the solvent comprises a solvent with a boiling point of 160°C or higher.

8. The resist underlayer film forming composition according to claim 1, further comprising at least one selected from the group consisting of acids and salts thereof, and acid generators.

9. The resist underlayer film forming composition according to claim 1, further comprising a crosslinking agent.

10. The resist underlayer film forming composition according to claim 9, wherein the crosslinking agent is at least one selected from the group consisting of aminoplast crosslinking agents and phenoplast crosslinking agents.

11. The resist underlayer film forming composition according to claim 1, further comprising a surfactant.

12. A resist underlayer film on a semiconductor substrate, which is a cured product of a resist underlayer film forming composition according to any one of claims 1 to 11.

13. A method for forming a resist pattern used in semiconductor manufacturing, comprising the step of applying a resist underlayer film forming composition according to any one of claims 1 to 11 onto a semiconductor substrate and firing it to form a resist underlayer film.

14. A method for manufacturing a semiconductor device, comprising the steps of: forming a resist underlayer film on a semiconductor substrate using a resist underlayer film forming composition according to any one of claims 1 to 11; forming a resist film on the resist underlayer film; forming a resist pattern by irradiating the resist film with light or an electron beam and developing it; etching the resist underlayer film through the resist pattern to form a patterned resist underlayer film; and processing a semiconductor substrate through the patterned resist underlayer film.

15. A method for manufacturing a semiconductor device, comprising the steps of: forming a resist underlayer film on a semiconductor substrate using a resist underlayer film forming composition according to any one of claims 1 to 11; forming a hard mask on the resist underlayer film; further forming a resist film on the hard mask; forming a resist pattern by irradiating the resist film with light or an electron beam and developing it; etching the hard mask through the resist pattern to form a patterned hard mask; etching the resist underlayer film through the patterned hard mask to form a patterned resist underlayer film; and processing the semiconductor substrate through the patterned resist underlayer film.

16. A method for manufacturing a semiconductor device, comprising the steps of: forming a resist underlayer film on a semiconductor substrate using a resist underlayer film forming composition according to any one of claims 1 to 11; forming a hard mask on the resist underlayer film; further forming a resist film on the hard mask; forming a resist pattern by irradiating the resist film with light or an electron beam and developing it; etching the hard mask through the resist pattern to form a patterned hard mask; etching the resist underlayer film through the patterned hard mask to form a patterned resist underlayer film; removing the hard mask; and processing the semiconductor substrate through the patterned resist underlayer film.

17. A method for manufacturing a semiconductor device, comprising the steps of: forming a resist underlayer film on a semiconductor substrate using a resist underlayer film forming composition according to any one of claims 1 to 11; forming a hard mask on the resist underlayer film; further forming a resist film on the hard mask; forming a resist pattern by irradiating the resist film with light or an electron beam and developing it; etching the hard mask through the resist pattern to form a patterned hard mask; etching the resist underlayer film through the patterned hard mask to form a patterned resist underlayer film; removing the hard mask; forming a vapor-deposited film on the resist underlayer film after removal of the hard mask; processing the vapor-deposited film by etching; removing the patterned resist underlayer film to leave the patterned vapor-deposited film; and processing the semiconductor substrate through the patterned vapor-deposited film.

18. The method for manufacturing a semiconductor device according to claim 15, wherein the hard mask is formed by coating a composition containing an inorganic substance or by depositing an inorganic substance.

19. The method for manufacturing a semiconductor device according to claim 14, wherein the resist film is patterned by nanoimprint or self-assembled film.

20. The method for manufacturing a semiconductor device according to claim 16, wherein the hard mask is removed by either dry etching or an alkaline chemical solution.

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