Resist underlayer film formation composition

Abstract

This resist underlayer film formation composition contains a resin (A), a solvent (B), and a surfactant (C). The surfactant (C) is a copolymer containing a constituent unit derived from a specific monomer.

Description

Composition for forming resist underlayer film

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

[0002] In the manufacture of semiconductor devices, microfabrication by lithography using a resist composition has traditionally been performed. This microfabrication process involves forming a thin film of a photoresist composition on a semiconductor substrate, such as a silicon wafer, irradiating the thin film with active light such as ultraviolet light through a mask pattern bearing a device pattern, developing the thin film, and etching the substrate using the resulting photoresist pattern as a protective film, thereby forming fine irregularities on the substrate surface corresponding to the photoresist pattern. In recent years, the integration density of semiconductor devices has increased, and in addition to the conventionally used i-line (wavelength 365 nm), KrF excimer laser (wavelength 248 nm), and ArF excimer laser (wavelength 193 nm), the practical use of EUV light (wavelength 13.5 nm) or EB (electron beam) is being considered for cutting-edge microfabrication. As a result, poor resist pattern formation due to influences from the semiconductor substrate, etc., has become a major problem. To address this issue, methods of providing a resist underlayer film between the resist and the semiconductor substrate have been widely investigated.

[0003] A resist underlayer film can be produced by applying a resist underlayer film-forming composition containing a polymer, a solvent, etc., onto a semiconductor substrate and baking the composition. With the diversification of semiconductor manufacturing processes, there is a demand for a resist underlayer film with small film thickness differences and good coverage (planarization properties) for various layouts on uneven substrates.

[0004] For example, Patent Document 1 proposes a composition for forming a resist underlayer film, which contains a surfactant having a perfluoroalkyl partial structure, for the purpose of improving the flatness of the surface of a coating film.

[0005] International Publication No. 2015 / 122296

[0006] Fluorine-containing surfactants are effective in improving planarization during film formation, but perfluoroalkyl compounds and polyfluoroalkyl compounds are called PFAS (Per and Polyfluoroalkyl Substances) and are restricted substances under the European REACH (Registration, Evaluation, Authorization and Restriction of Chemicals) regulations, and regulations on their use are expected to become increasingly strict in the future. Therefore, there is a strong demand for the use of surfactants that do not fall under PFAS. Silicone-based surfactants are known as non-fluorine-based surfactants with good planarization properties, but when an organic resist underlayer film is used, it is desirable to use organic surfactants from the viewpoint of dry etching selectivity.

[0007] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a composition for forming a resist underlayer film using a non-fluorinated organic surfactant, as well as methods for producing a resist underlayer film, a laminate, and a semiconductor element, and a pattern forming method, all of which use the composition for forming a resist underlayer film.

[0008] The present inventors have conducted extensive research to solve the above problems, and as a result have found that the above problems can be solved, and have completed the present invention having the following gist.

[0009] That is, the present invention encompasses the following aspects: [1] A composition for forming a resist underlayer film, comprising a resin (A), a solvent (B), and a surfactant (C), wherein the surfactant (C) is a copolymer containing structural units derived from monomers represented by the following formulas (I), (II), and (III): (In formula (I), R １ represents a hydrogen atom or a methyl group, R ２ represents an alkylene group having 1 to 4 carbon atoms, R ３ represents an aliphatic hydrocarbon group having 10 to 30 carbon atoms. ４ and R ５may be the same or different and represent a hydrogen atom or a methyl group, AO represents an oxyalkylene group having 2 to 4 carbon atoms, and n is the average number of moles added and is 1 to 200. In formula (III), R ６ is an aliphatic hydrocarbon group having 1 to 12 carbon atoms.) [2] The composition for forming a resist underlayer film according to [1], wherein the surfactant (C) is a copolymer containing structural units derived from two or more types of monomers represented by formula (I). [3] The composition for forming a resist underlayer film according to [1] or [2], wherein the resin (A) contains at least one selected from the group consisting of polyester resins, acrylic resins, methacrylic resins, resins containing an aromatic ring, polyether resins, arylene resins, triazine resins, and calixarene resins. [4] The composition for forming a resist underlayer film according to any of [1] to [3], wherein the resin (A) has a repeating unit represented by formula (1) below: (In the formula, A's each independently represent a hydrogen atom, a methyl group, or an ethyl group; Q １ and Q ２ represents the following formula (2) or the following formula (3): (In formula (2), Q ３ represents an alkylene group having 1 to 10 carbon atoms, which may contain a sulfide bond or a disulfide bond, an alkenylene group having 2 to 10 carbon atoms, a phenylene group, a naphthylene group, or an anthrylene group. The phenylene group, naphthylene group, and anthrylene group may each independently be substituted with a group selected from the group consisting of an alkyl group having 1 to 6 carbon atoms, a phenyl group, a halogen atom, an alkoxy group having 1 to 6 carbon atoms, a nitro group, a cyano group, a hydroxy group, and an alkylthio group having 1 to 6 carbon atoms. In formula (3), each B independently represents a single bond or an alkylene group having 1 to 5 carbon atoms. In formulas (2) and (3), * represents a bond. Each n independently represents 0 or 1. Each m independently represents 0 or 1. Each X independently represents a group represented by formula (4), (5), or (6) below. (In formula (4) and formula (5), R １are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 3 to 6 carbon atoms, a benzyl group, or a phenyl group. The alkyl group and alkenyl group may be substituted with a halogen atom, a hydroxy group, or a cyano group. The benzyl group may have a hydrogen atom on the aromatic ring substituted with a hydroxy group. The phenyl group may be substituted with a group selected from the group consisting of an alkyl group having 1 to 6 carbon atoms, a halogen atom, an alkoxy group having 1 to 6 carbon atoms, a nitro group, a cyano group, a hydroxy group, and an alkylthio group having 1 to 6 carbon atoms, and two R １ may be bonded to each other to form a ring having 3 to 6 carbon atoms. ２ represents a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 3 to 6 carbon atoms, a benzyl group, or a phenyl group. The phenyl group may be substituted with a group selected from the group consisting of an alkyl group having 1 to 6 carbon atoms, a halogen atom, an alkoxy group having 1 to 6 carbon atoms, a nitro group, a cyano group, a hydroxy group, and an alkylthio group having 1 to 6 carbon atoms. １ and Q ２ At least one of the above contains a structure represented by formula (3): [5] The composition for forming a resist underlayer film according to any one of [1] to [4], wherein the resin (A) has a composite unit structure represented by the following formula (AB): (In formula (AB), A represents a unit structure (A) having an aromatic ring, and B represents a unit structure (B) having one or more carbon atoms.) [6] The composition for forming a resist underlayer film according to any one of [1] to [5], wherein the solvent (B) comprises at least one selected from the group consisting of alkylene glycol monoalkyl ethers and monocarboxylic acid esters of alkylene glycol monoalkyl ethers. [7] The composition for forming a resist underlayer film according to any one of [1] to [6], further comprising a crosslinking agent (D). [8] The composition for forming a resist underlayer film according to [7], wherein the crosslinking agent (D) is at least one selected from the group consisting of aminoplast crosslinking agents and phenoplast crosslinking agents. [9] The composition for forming a resist underlayer film according to any one of [1] to [8], further comprising a curing catalyst (E).

[10] A resist underlayer film, which is a cured product of the composition for forming a resist underlayer film according to any one of [1] to [9].

[11] A laminate comprising a semiconductor substrate and the resist underlayer film according to

[10] .

[12] A method for manufacturing a semiconductor device, comprising: forming a resist underlayer film on a semiconductor substrate using the composition for forming a resist underlayer film according to any one of [1] to [9], and forming a resist film on the resist underlayer film.

[13] A pattern formation method, comprising: forming a resist underlayer film on a semiconductor substrate using the composition for forming a resist underlayer film according to any one of [1] to [9], forming a resist film on the resist underlayer film, irradiating the resist film with light or an electron beam and then developing the resist film to obtain a resist pattern, and etching the resist underlayer film using the resist pattern as a mask.

[0010] According to the present invention, it is possible to provide a composition for forming a resist underlayer film using a non-fluorinated organic surfactant, as well as a method for producing a resist underlayer film, a laminate, and a semiconductor element, and a method for forming a pattern, all of which use the composition for forming a resist underlayer film.

[0011] (Composition for forming a resist underlayer film) The composition for forming a resist underlayer film of the present invention contains a resin (A), a solvent (B), and a surfactant (C). The composition for forming a resist underlayer film may also contain a crosslinking agent (D), a curing catalyst (E), etc. By including the surfactant (C), the composition for forming a resist underlayer film can improve hump height.

[0012] <Resin (A)> The resin (A) is not particularly limited, and examples thereof include the following resins, polyester resins, acrylic resins, methacrylic resins, resins containing an aromatic ring, polyether resins, arylene resins, triazine resins, and calixarene resins, or combinations thereof. The resin may be a polymer, oligomer, or low-molecular-weight compound.

[0013] <<Resin (A-1)>> Resin (A-1) can be synthesized by a ring-opening reaction of a polyfunctional epoxy compound, but the synthesis method is not limited. The polyfunctional epoxy compound is a compound having two or more epoxy groups.

[0014] The resin (A) is preferably a resin (A-1) having a repeating unit represented by the following formula (1):

[0015]

[0016] In the formula, A's each independently represent a hydrogen atom, a methyl group, or an ethyl group; １ and Q ２ represents formula (2) or formula (3).

[0017]

[0018] In formula (2), Q ３represents an alkylene group having 1 to 10 carbon atoms, which may contain a sulfide bond or a disulfide bond, an alkenylene group having 2 to 10 carbon atoms, a phenylene group, a naphthylene group, or an anthrylene group. The phenylene group, naphthylene group, and anthrylene group may each independently be substituted with a group selected from the group consisting of an alkyl group having 1 to 6 carbon atoms, a phenyl group, a halogen atom, an alkoxy group having 1 to 6 carbon atoms, a nitro group, a cyano group, a hydroxy group, and an alkylthio group having 1 to 6 carbon atoms. In formula (3), each B independently represents a single bond or an alkylene group having 1 to 5 carbon atoms. In formulas (2) and (3), * represents a bond. Each n independently represents 0 or 1. Each m independently represents 0 or 1. Each X is a group represented by formula (4), formula (5), or formula (6).

[0019]

[0020] In formula (4) and formula (5), R １ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 3 to 6 carbon atoms, a benzyl group, or a phenyl group. The alkyl group and alkenyl group may be substituted with a halogen atom, a hydroxy group, or a cyano group. The benzyl group may have a hydrogen atom on the aromatic ring substituted with a hydroxy group. The phenyl group may be substituted with a group selected from the group consisting of an alkyl group having 1 to 6 carbon atoms, a halogen atom, an alkoxy group having 1 to 6 carbon atoms, a nitro group, a cyano group, a hydroxy group, and an alkylthio group having 1 to 6 carbon atoms, and two R １ may be bonded to each other to form a ring having 3 to 6 carbon atoms.

[0021] In formula (6), R ２ represents a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 3 to 6 carbon atoms, a benzyl group, or a phenyl group. The phenyl group may be substituted with a group selected from the group consisting of an alkyl group having 1 to 6 carbon atoms, a halogen atom, an alkoxy group having 1 to 6 carbon atoms, a nitro group, a cyano group, a hydroxy group, and an alkylthio group having 1 to 6 carbon atoms.

[0022] However, Q １ and Q２ At least one of the above contains a structure represented by formula (3).

[0023] The alkylene group having 1 to 10 carbon atoms may be linear, branched, or cyclic, and examples thereof include methylene, ethylene, propylene, pentamethylene, cyclohexylene, 2-methylpropylene, and 1-methylethylidene. Furthermore, the alkylene group having 1 to 10 carbon atoms and containing a sulfide bond or a disulfide bond includes alkylene groups containing a sulfide bond or a disulfide bond represented by the following formula:

[0024] (In the formula, * represents a bond.)

[0025] The alkenylene group having 2 to 10 carbon atoms may be straight-chain, branched or cyclic, and examples thereof include ethenylene, propenylene, butenylene, pentenylene, hexenylene, heptenylene, octenylene and nonenylene groups.

[0026] The alkyl group having 1 to 6 carbon atoms may be linear, branched, or cyclic, and examples thereof include methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, t-butyl, n-pentyl, i-pentyl, neopentyl, n-hexyl, cyclopentyl, and cyclohexyl groups.

[0027] The alkoxy group having 1 to 6 carbon atoms may be linear, branched or cyclic, and examples thereof include methoxy, ethoxy, i-propoxy, n-pentyloxy, n-hexyloxy and cyclohexyloxy groups.

[0028] The alkylthio group having 1 to 6 carbon atoms may be linear, branched or cyclic, and examples thereof include methylthio, ethylthio, i-propylthio, n-pentylthio and cyclohexylthio groups.

[0029] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0030] Two R's １Examples of the ring having 3 to 6 carbon atoms formed by bonding include a cyclobutane ring, a cyclopentane ring, and a cyclohexane ring.

[0031] Examples of the repeating unit represented by formula (1) include, but are not limited to, those represented by the following formulas (7) to (31), in which Me is a methyl group.

[0032]

[0033] [wherein X represents a group represented by formula (4), formula (5) or formula (6), R ６ and R ７ each independently represents an alkylene group having 1 to 3 carbon atoms or a direct bond, and p is the number of repeating structural units and represents an integer of 5 to 100. [wherein X represents a group represented by formula (4), formula (5) or formula (6), R ６ and R ７ each independently represents an alkylene group having 1 to 3 carbon atoms or a direct bond; R ８ represents an alkylene group having 1 to 3 carbon atoms, m represents 0 or 1, and r represents the number of repeating structural units and is an integer of 5 to 100.

[0034]

[0035]

[0036]

[0037]

[0038]

[0039] In the above formula (31), R is an alcohol residue (an organic group other than the hydroxyl group of an alcohol), and this R represents an alkyl group, an ether group, or a combination thereof. Examples of the R include an alkyl group and an alkoxyalkyl group. Examples of the alkyl group and the alkoxy group include those described above.

[0040] In the composition for forming a resist underlayer film, the resin (A-1) may be a single polymer or a combination of two or more polymers.

[0041] The molecular weight of the resin (A-1) contained in the composition for forming a resist underlayer film is, in terms of weight average molecular weight, for example, 1,000 to 200,000, or for example, 3,000 to 100,000, or 5,000 to 20,000.

[0042] Resin (A-1) having a repeating unit represented by formula (1) can be synthesized by a method including the following steps 1 and 2. In the following description, a crude polymer refers to a polymer synthesized in step 1, and a purified polymer refers to a polymer obtained from a solution containing the crude polymer through step 2.

[0043] <First Step> The first step is a step of reacting a monomer represented by the following formula (a) (hereinafter sometimes abbreviated as component (a)) with a monomer represented by the following formula (b) (hereinafter sometimes abbreviated as component (b)) in an organic solvent in the presence of a quaternary phosphonium salt or a quaternary ammonium salt to synthesize a crude polymer having a repeating unit represented by the following formula (1):

[0044]

[0045] In the formula, A, Q １ and Q ２ is the same as above.

[0046] Specific examples of component (a) include the following: １ Examples of the compound in which is a group represented by formula (2) include diglycidyl ester compounds and diglycidyl ether compounds.

[0047] Examples of the diglycidyl ester compound include terephthalic acid diglycidyl ester, isophthalic acid diglycidyl ester, phthalic acid diglycidyl ester, 2,5-dimethylterephthalic acid diglycidyl ester, 2,5-diethylterephthalic acid diglycidyl ester, 2,3,5,6-tetrachloroterephthalic acid diglycidyl ester, 2,3,5,6-tetrabromoterephthalic acid diglycidyl ester, 2-nitroterephthalic acid diglycidyl ester, and 2,3,5,6-tetrafluoroterephthalic acid diglycidyl ester. Oroterephthalic acid diglycidyl ester, 2,5-dihydroxyterephthalic acid diglycidyl ester, 2,6-dimethylterephthalic acid diglycidyl ester, 2,5-dichloroterephthalic acid diglycidyl ester, 2,3-dichloroisophthalic acid diglycidyl ester, 3-nitroisophthalic acid diglycidyl ester, 2-bromoisophthalic acid diglycidyl ester, 2-hydroxyisophthalic acid diglycidyl ester, 3-hydroxyisophthalic acid diglycidyl ester, 2-methoxyisophthalic acid diglycidyl ester Diisophthalic acid diglycidyl ester, 5-phenylisophthalic acid diglycidyl ester, 3-nitrophthalic acid diglycidyl ester, 3,4,5,6-tetrachlorophthalic acid diglycidyl ester, 4,5-dichlorophthalic acid diglycidyl ester, 4-hydroxyphthalic acid diglycidyl ester, 4-nitrophthalic acid diglycidyl ester, 4-methylphthalic acid diglycidyl ester, 3,4,5,6-tetrafluorophthalic acid diglycidyl ester, 2,6-naphthalenedicarboxylic acid diglycidyl ester diglycidyl ester of 1,2-naphthalenedicarboxylic acid, diglycidyl ester of 1,4-naphthalenedicarboxylic acid, diglycidyl ester of 1,8-naphthalenedicarboxylic acid, diglycidyl ester of anthracene-9,10-dicarboxylic acid, diglycidyl ester of 1,2-cyclohexanedicarboxylic acid, diglycidyl ester of dithiodiglycolic acid, diglycidyl ester of 2,2′-thiodiglycolic acid, and diglycidyl ester of diglycolic acid.

[0048] Examples of diglycidyl ether compounds include ethylene glycol diglycidyl ether, 1,3-propanediol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,5-pentanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, 1,2-benzenediol diglycidyl ether, 1,3-benzenediol diglycidyl ether, 1,4-benzenediol diglycidyl ether, and 1,6-naphthalenediol diglycidyl ether.

[0049] Q １ is a group represented by formula (3), for example, a diglycidyl hydantoin compound, a diglycidyl barbituric acid compound, or a diglycidyl isocyanuric acid compound.

[0050] Examples of diglycidyl barbituric acid compounds include 1,3-diglycidyl-5,5-diethylbarbituric acid, 1,3-diglycidyl-5-phenyl-5-ethylbarbituric acid, 1,3-diglycidyl-5-ethyl-5-isoamylbarbituric acid, 1,3-diglycidyl-5-allyl-5-isobutylbarbituric acid, 1,3-diglycidyl-5-allyl-5-isopropylbarbituric acid, 1,3-diglycidyl-5-β-bromoallyl-5-sec-butyl ... Examples thereof include glycidyl-5-ethyl-5-(1-methyl-1-butenyl)barbituric acid, 1,3-diglycidyl-5-isopropyl-5-β-bromoallyl barbituric acid, 1,3-diglycidyl-5-(1-cyclohexyl)-5-ethylmalonyl urea, 1,3-diglycidyl-5-ethyl-5-(1-methylbutyl)malonyl urea, 1,3-diglycidyl-5,5-diallylmalonyl urea diglycidyl, and 1,3-diglycidyl-5-ethyl-5-normal butyl barbituric acid.

[0051] Examples of diglycidyl isocyanuric acid compounds include monoallyl diglycidyl isocyanuric acid, monomethyl diglycidyl isocyanuric acid, monoethyl diglycidyl isocyanuric acid, monopropyl diglycidyl isocyanuric acid, monomethylthiomethyl diglycidyl isocyanuric acid, monoisopropyl diglycidyl isocyanuric acid, monomethoxymethyl diglycidyl isocyanuric acid, monobutyl diglycidyl isocyanuric acid, monomethoxyethoxymethyl diglycidyl isocyanuric acid, monophenyl diglycidyl isocyanuric acid, monobromo diglycidyl isocyanuric acid, monoallyl isocyanuric acid diglycidyl ester, and monomethyl isocyanuric acid diglycidyl ester.

[0052] Specific examples of component (b) include the following: ２ However, examples of compounds having the group represented by formula (2) include dicarboxylic acid compounds.

[0053] Examples of dicarboxylic acid compounds include terephthalic acid, isophthalic acid, phthalic acid, 2,5-dimethylterephthalic acid, 2,5-diethylterephthalic acid, 2,3,5,6-tetrachloroterephthalic acid, 2,3,5,6-tetrabromoterephthalic acid, 2-nitroterephthalic acid, 2,3,5,6-tetrafluoroterephthalic acid, 2,5-dihydroxyterephthalic acid, 2,6-dimethylterephthalic acid, 2,5-dichloroterephthalic acid, 2,3-dichloroisophthalic acid, 3-nitroisophthalic acid, 2-bromoisophthalic acid, 2-hydroxyisophthalic acid, 3-hydroxyisophthalic acid, 2-methoxyisophthalic acid, 5-phenylisophthalic acid, 3-nitrophthalic acid, 3,4,5,6-tetrachlorophthalic acid, 4,5-dichloro Examples of suitable carboxylic acids include 4-hydroxyphthalic acid, 4-nitrophthalic acid, 4-methylphthalic acid, 3,4,5,6-tetrafluorophthalic acid, 2,6-naphthalenedicarboxylic acid, 1,2-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, anthracene-9,10-dicarboxylic acid, ethylene glycol, 1,3-propanedicarboxylic acid, 4-hydroxybenzoic acid, fumaric acid, dithiodiglycolic acid, 2,2'-thiodiglycolic acid, tartaric acid, malonic acid, succinic acid, glutaric acid, adipic acid, itaconic acid, 3,3'-(5-methyl-2,4,6-trioxo-1,3,5-triazine-1,3-diyldipropionic acid, and 3,3'-dithiodipropionic acid.

[0054] Q ２ Examples of the compound in which is a group represented by formula (3) include hydantoin compounds, barbituric acid compounds, and isocyanuric acid compounds.

[0055] Examples of the hydantoin compound include hydantoin, 5,5-diphenylhydantoin, 5,5-dimethylhydantoin, 5-ethylhydantoin, 5-benzylhydantoin, 5-ethyl-5-phenylhydantoin, 5-methylhydantoin, 5,5-tetramethylenehydantoin, 5,5-pentamethylenehydantoin, 5-(4-hydroxybenzyl)-hydantoin, 5-phenylhydantoin, 5-hydroxymethylhydantoin, and 5-(2-cyanoethyl)hydantoin.

[0056] Examples of barbituric acid compounds include barbituric acid, 5,5-dimethylbarbituric acid, 5,5-diethylbarbituric acid (also known as barbital), 5-methyl-5-ethylbarbituric acid, 5,5-diallylbarbituric acid (also known as allobarbital), 5-ethyl-5-phenylbarbituric acid (also known as phenobarbital), 5-ethyl-5-isopentylbarbituric acid (also known as amobarbital), 5,5-diallylmalonylurea, 5-ethyl-5-isoamylbarbituric acid, and 5-allyl-5-isobutyric acid. Examples of barbituric acid include 5-allyl-5-isopropylbarbituric acid, 5-β-bromoallyl-5-sec-butylbarbituric acid, 5-ethyl-5-(1-methyl-1-butenyl)barbituric acid, 5-isopropyl-5-β-bromoallylbarbituric acid, 5-(1-cyclohexyl)-5-ethylmalonylurea, 5-ethyl-5-(1-methylbutyl)malonylurea, 5,5-dibromobarbituric acid, 5-phenyl-5-ethylbarbituric acid, and 5-ethyl-5-normal butylbarbituric acid.

[0057] Examples of the isocyanuric acid compound include monoallyl isocyanuric acid, monomethyl isocyanuric acid, monoethyl isocyanuric acid, monopropyl isocyanuric acid, monoisopropyl isocyanuric acid, monophenyl isocyanuric acid, monobenzyl isocyanuric acid, and monochloroisocyanuric acid.

[0058] The components (a) and (b) exemplified above can usually be combined by selecting one compound from each of them, but this is not limited thereto, and multiple compounds may be selected and used for either or both of the components (a) and (b), provided that at least one of the components (a) and (b) contains a compound having a skeleton selected from hydantoin, barbituric acid, and isocyanuric acid.

[0059] Examples of the component (a) that can be suitably used in the present invention include the following compounds, but the component (a) is not limited to these.

[0060]

[0061] In addition, examples of the component (b) that can be suitably used in the present invention include the following compounds, but are not limited to these.

[0062]

[0063] The blending ratio (molar ratio) of component (a) and component (b) is not particularly limited, but from the viewpoint of suppressing the remaining unreacted epoxy group-containing component (a), it is preferable that component (a) and component (b) are equimolar, or that component (b) is in excess relative to component (a), and more preferably (a):(b) = 1:1.21 to 1:1. By keeping the blending ratio at or below the upper limit, it becomes easier to obtain a polymer having the desired Mw.

[0064] Examples of quaternary phosphonium salts include methyltriphenylphosphonium bromide, ethyltriphenylphosphonium bromide, butyltriphenylphosphonium bromide, hexyltriphenylphosphonium bromide, tetrabutylphosphonium bromide, benzyltriphenylphosphonium bromide, methyltriphenylphosphonium chloride, ethyltriphenylphosphonium chloride, butyltriphenylphosphonium chloride, hexyltriphenylphosphonium chloride, tetrabutylphosphonium chloride, benzyltriphenylphosphonium chloride, methyltriphenylphosphonium iodide, ethyltriphenylphosphonium iodide, butyltriphenylphosphonium iodide, hexyltriphenylphosphonium iodide, tetrabutylphosphonium iodide, and benzyltriphenylphosphonium iodide. In the present invention, ethyltriphenylphosphonium bromide or tetrabutylphosphonium bromide can be preferably used.

[0065] Examples of quaternary ammonium salts include tetramethylammonium fluoride, tetramethylammonium chloride, tetramethylammonium bromide, tetramethylammonium nitrate, tetramethylammonium sulfate, tetramethylammonium acetate, tetraethylammonium chloride, tetraethylammonium bromide, tetrapropylammonium chloride, tetrapropylammonium bromide, tetrabutylammonium fluoride, tetrabutylammonium chloride, tetrabutylammonium bromide, benzyltrimethylammonium chloride, phenyltrimethylammonium chloride, benzyltriethylammonium chloride, methyltributylammonium chloride, benzyltributylammonium chloride, methyltrioctylammonium chloride, etc. In the present invention, benzyltriethylammonium chloride can be preferably used.

[0066] The amount of the quaternary phosphonium salt and quaternary ammonium salt to be added is not particularly limited as long as it is an amount that allows the reaction to proceed, but is preferably 0.1 to 10.0%, and more preferably 1.0 to 5.0%, based on the number of moles of component (a).

[0067] The organic solvent used in the first step may be any solvent that does not affect the reaction, and examples thereof include benzene, toluene, xylene, ethyl lactate, butyl lactate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, cyclohexanone, and N-methylpyrrolidone. These may be used alone or in combination of two or more. In the present invention, propylene glycol monomethyl ether is preferred, taking into consideration the intended use of the composition using the final polymer obtained.

[0068] The amount of organic solvent used can be appropriately set depending on the type and amount of each of the above components, and is not particularly limited. In the present invention, in consideration of efficiently progressing the reaction, the amount is preferably such that the total solid content concentration of the above components is 5 to 40 mass%, more preferably 10 to 30 mass%, and even more preferably 15 to 25 mass%. In the present invention, the solid content means the components other than the solvent that constitute the solution.

[0069] The reaction temperature in the first step is usually 200° C. or lower, and considering the boiling point of the organic solvent used, it is preferably 150° C. or lower, and more preferably 130° C. or lower. There are no particular restrictions on the lower limit of the reaction temperature, but considering the need to quickly complete the condensation reaction of components (a) and (b), it is preferably 50° C. or higher, and more preferably 60° C. or higher. Furthermore, reflux may be performed during heating.

[0070] The reaction time cannot be generally determined because it depends on the reaction temperature and the reactivity of the raw materials, but it is usually about 1 to 48 hours, and when the reaction temperature is 60 to 130°C, it is generally about 15 to 30 hours.

[0071] <Second Step> The second step is a step of mixing a solution containing the crude polymer obtained in the first step (hereinafter referred to as the crude polymer solution) with a poor solvent to precipitate a crude polymer having a repeating unit represented by formula (1), followed by filtration. The second step makes it possible to remove low-molecular-weight components contained in the crude polymer. Here, the crude polymer solution may be the reaction solution obtained in the first step as is, or may be a solution obtained by dissolving a crude polymer isolated by an appropriate means such as drying in an appropriate solvent. In the latter case, the organic solvent used in the first step may be used as the solvent.

[0072] The poor solvent used in the second step can be a solvent in which the polymer has low solubility and in which low-molecular-weight components are soluble, such as diethyl ether, cyclopentyl methyl ether, diisopropyl ether, or isopropyl alcohol. These can be used alone or in combination of two or more. In the present invention, isopropyl alcohol can be preferably used.

[0073] In the present invention, when the crude polymer solution and the poor solvent are mixed, the order of mixing is not particularly limited, and the crude polymer solution may be added to the poor solvent, or the poor solvent may be added to the crude polymer solution. However, in consideration of removing as many low-molecular-weight components as possible, the method of adding the crude polymer solution to the poor solvent is preferred.

[0074] When mixing the two, they may be added gradually by dropwise addition or the entire amount may be added all at once. However, in consideration of reducing the content of low molecular weight components in the purified polymer, the method of adding them gradually by dropwise addition is preferred.

[0075] The amount of the poor solvent used relative to the crude polymer solution is not particularly limited as long as it is an amount that does not cause precipitation of low-molecular-weight components and can sufficiently precipitate the polymer, but is preferably 2 to 30 times by mass, more preferably 5 to 20 times by mass, and even more preferably 5 to 15 times by mass, relative to the total mass of the crude polymer solution.

[0076] The temperature during mixing may be appropriately set within the range from the melting point of the solvent to the boiling point of the solvent, and is not particularly limited. However, it can usually be set to about −20 to 50° C., and in consideration of the ease of precipitation and workability, the temperature is preferably 0 to 50° C., and more preferably 0 to 30° C.

[0077] A preferred embodiment of the above-mentioned mixing operation is, for example, a method in which a crude polymer solution having a total solids concentration of 5 to 50% by mass is gradually added to a poor solvent in an amount of 5 to 20 times by mass, in which the poor solvent is gradually added over 15 minutes to 1 hour per 50 g of crude polymer solution, but is not limited thereto.

[0078] After the mixing operation is completed, stirring may be continued for a predetermined period of time to remove more of the low molecular weight components. In this case, the stirring time is preferably 10 minutes to 2 hours, more preferably 15 minutes to 1 hour.

[0079] In order to further reduce the polydispersity of the polymer, a step may be carried out in which the precipitate separated by filtration in the second step is dissolved again in the organic solvent used in the first step, the resulting solution is mixed with the poor solvent, and the resulting precipitate is separated by filtration.

[0080] The second step described above can remove 30% by mass or more, preferably 40% by mass or more, more preferably 70% by mass or more, and even more preferably 90% by mass or more of the low-molecular-weight components contained in the crude polymer, and ultimately yields a polymer (purified polymer) having a low-molecular-weight component content of 10% by mass or less, preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 1% by mass or less.

[0081] The Mw of the resulting purified polymer is generally 1,000 to 200,000, preferably 3,000 to 100,000, more preferably 4,000 to 47,000, even more preferably 7,000 to 47,000, and still more preferably 7,000 to 27,000. In the present invention, Mw is a polystyrene-equivalent value measured by gel permeation chromatography (GPC).

[0082] Resin (A-1) includes polymers described in WO 2009 / 096340, WO 2021 / 111976, WO 2021 / 111977 and WO 2013 / 018802. The contents of WO 2009 / 096340, WO 2021 / 111976, WO 2021 / 111977 and WO 2013 / 018802 are incorporated herein by reference in their entirety to the same extent as if expressly set forth herein.

[0083] <<Resin (A-2)>> The resin (A) may contain a (meth)acrylic resin (A-2). Examples of the (meth)acrylic resin (A-2) include a polymer containing (meth)acrylic acid, a (meth)acrylic acid ester, or a vinyl compound. In this specification, the term "(meth)acrylic resin" refers to both or either an acrylic resin and a methacrylic resin. Similarly, the term "(meth)acrylic acid" refers to both or either an acrylic acid and a methacrylic acid, and the term "(meth)acrylic acid ester" refers to both or either an acrylic acid ester and a methacrylic acid ester.

[0084] Examples of (meth)acrylic acid esters include lactone (meth)acrylates such as γ-butyrolactone (meth)acrylate, alkyl (meth)acrylates, hydroxyalkyl (meth)acrylates such as hydroxyethyl methacrylate, (meth)acrylamides, and aromatic (meth)acrylates such as phenyl (meth)acrylate and benzyl (meth)acrylate. In this specification, (meth)acrylate refers to both or either of acrylate and methacrylate.

[0085] Examples of vinyl compounds include vinyl ethers such as alkyl vinyl ether and vinyl aryl ether, and styrenes such as styrene, hydroxystyrene, and alkoxystyrene. The vinyl compounds may be polymerized to form random copolymers, block copolymers, or graft copolymers. The resins forming the resist underlayer film of the present invention can be synthesized by radical polymerization, anionic polymerization, cationic polymerization, or other methods. Various methods, such as solution polymerization, suspension polymerization, emulsion polymerization, and bulk polymerization, are possible.

[0086] <<Resin (A-3)>> Resin (A) may include resin (A-3). Resins suitable as resin (A-3) are disclosed in U.S. Patent Nos. 5,939,236; 5,886,102; 5,851,738; and 5,851,730. Particularly preferred resins for use in the resist underlayer film-forming composition of the present invention contain ester repeat units. Preferably, the ester groups are not photoacid-labile. That is, the ester repeat units do not undergo deblocking or other cleavage during typical lithographic processes such as pre-exposure baking, exposure to actinic radiation, post-exposure heating, and / or development. Preferably, the ester repeat units are present in the polymer backbone. That is, the ester group (—(C═O)O—) is present in a branched or substantially linear chain that forms the polymer chain. It is also preferred that such ester groups have an aromatic substituent, for example, a phenyl, naphthyl, or anthracene substituent such as obtained by reacting an alkyl phthalate with a polyol.

[0087] Such polyester resins may contain other repeating units, either as pendant or side chain units or as other repeating units in the polymer backbone. For example, the resins can be copolymers (e.g., those with two different repeating units in the resin backbone), terpolymers (e.g., those with three different repeating units in the resin backbone), tetrapolymers (e.g., those with four different repeating units in the resin backbone), or pentapolymers (e.g., those with five different repeating units in the resin backbone). For example, polymers containing ether and ester groups, and polymers containing alkylene repeating units with ether and ester groups are suitable. Additional repeating units containing one or more oxygen atoms are preferred in many applications.

[0088] Examples of preferred resins that can be used in the resist underlayer film-forming composition of the present invention include those formed by reacting a compound having one or more carbonyl groups (e.g., an ester, an acid anhydride, or a carboxylic acid) with a compound having one or more hydroxy groups, preferably at least two hydroxy groups. The carboxy-containing compound also preferably contains two or more carboxy groups (-(C=O)-O-H). The carboxy and hydroxy compounds are reacted, preferably in the presence of an acid, optionally with other compounds if a copolymer or higher polymer is desired, to provide a polyester resin.

[0089] Such polyester resins are preferably prepared by charging a reaction vessel with a polyol, a carboxylate compound, and any other compounds to be incorporated into the resin, and an acid, such as a sulfonic acid, such as methanesulfonic acid or paratoluenesulfonic acid. The reaction mixture is preferably stirred at an elevated temperature, e.g., at least about 80°C, more typically at least about 100°C, 110°C, 120°C, 130°C, 140°C, or 150°C, for a time sufficient to form the polymer, e.g., at least about 2, 3, 4, 5, 6, 8, 12, 16, 20, or 24 hours.

[0090] In antireflective applications, one or more compounds are preferably reacted to form a resin containing moieties that function as chromophores for absorbing radiation used to expose an overcoated photoresist coating layer. For example, phthalate compounds (e.g., phthalic acid or dialkyl phthalates (i.e., diesters, e.g., each ester having 1-6 carbon atoms, preferably dimethyl or diethyl phthalate)) are polymerized with aromatic or non-aromatic polyols, and optionally other reactive compounds, to provide polyesters useful in compositions for use with photoresists imaged at sub-200 nm wavelengths, e.g., 193 nm. Similarly, resins useful in compositions for use with overcoated photoresists imaged at sub-300 nm or sub-200 nm wavelengths, e.g., 248 nm or 193 nm, include naphthyl compounds, e.g., naphthyl compounds having one, two, or more carboxy substituents, e.g., dialkyl, especially di-C １－６ Alkyl naphthalene dicarboxylates can be polymerized. Also preferred are reactive anthracene compounds, such as anthracene compounds having one or more carboxy or ester groups, such as one or more methyl ester or ethyl ester groups.

[0091] The compound having a chromophore unit can have one or, preferably, two or more hydroxy groups and can be reacted with a carboxy-containing compound. For example, a phenyl or anthracene compound having one, two, or more hydroxy groups can be reacted with a carboxy-containing compound.

[0092] Additionally, the resist underlayer film composition may contain a material having a chromophore unit different from that of the polyester resin component. For example, the composition may contain a polymeric or non-polymeric compound having a phenyl, anthracene, naphthyl, or other unit. However, it is often preferred that the ester resin contain the chromophore moiety.

[0093] Examples of the resin (A-3) include the polymers described in Japanese Patent No. 4478379. The contents of Japanese Patent No. 4478379 are incorporated herein by reference in their entirety to the same extent as if set forth explicitly.

[0094] <<Resin (A-4)>> The resin (A) may contain a polyether-based resin (A-4). The polyether-based resin is preferably a linear resin containing an ether bond in the main chain. A polyether resin in which alicyclic hydrocarbon rings are connected by ether bonds can be preferably used. These polyether resins have a structure in which an epoxy group is attached to an alicyclic hydrocarbon ring, and examples thereof include a 1,2-epoxy-4-(2-oxiranyl)cyclohexane adduct of 2,2-bis(hydroxymethyl)-1-butanol (manufactured by Daicel Chemical Industries, Ltd., trade name EHPE3150) and a 1,2-epoxy-4-(2-oxiranyl)cyclohexane adduct of 2,2-bis(hydroxymethyl)-1-butanol and 3,4-epoxycyclohexenylmethyl-3',4'-epoxycyclohexenecarboxylate (manufactured by Daicel Chemical Industries, Ltd., trade name EHPE3150CE). Polyether resins can also be used by reacting the epoxy groups of the above-mentioned epoxy-containing polyether resins with fused-ring aromatic carboxylic acids or monocyclic aromatic carboxylic acids. The fused-ring aromatic carboxylic acids and monocyclic aromatic carboxylic acids are preferably carboxylic acids having a ring formed from benzene or its fused rings. The fused-ring aromatic carboxylic acids are, for example, carboxylic acids having a polycyclic structure formed by condensing benzene rings, such as naphthalenecarboxylic acid and anthracenecarboxylic acid, with 9-anthracenecarboxylic acid being particularly preferred. Benzoic acid is preferably used as the monocyclic aromatic carboxylic acid. Furthermore, a mixture of the fused-ring aromatic carboxylic acid and the monocyclic aromatic carboxylic acid can also be used, preferably in a molar ratio of 3:7 to 7:3, preferably 4:6 to 6:4.

[0095] <<Resin (A-5)>> The resin (A) may contain a resin (A-5). Examples of the resin (A-5) include a polymer having a composite unit structure represented by the following formula (AB). The resin (A-5) is a resin obtained by a reaction that forms a covalent bond between a carbon atom constituting an aromatic ring of the unit structure (A) described below and a carbon atom in the unit structure (B) described below.

[0096] (In formula (AB), A represents a unit structure (A) having an aromatic ring, and B represents a unit structure (B) having one or more carbon atoms.)

[0097] <<<A-1: Unit Structure (A)>>> The unit structure (A) has an aromatic ring. The unit structure (A) has, for example, at least one of an oxygen atom constituting the aromatic ring, a sulfur atom constituting the aromatic ring, an oxygen atom bonded to the aromatic ring, a nitrogen atom constituting the aromatic ring, and a nitrogen atom directly bonded to the aromatic ring. The unit structure (A) does not have a heteroatom, for example, as an atom constituting the aromatic ring or an atom bonded to the aromatic ring.

[0098] The number of carbon atoms contained in the unit structure (A) is not particularly limited, but is, for example, 4 to 100, and preferably 4 to 50.

[0099] Preferably, such aromatic rings have from 4 to 30, more preferably from 4 to 24, carbon atoms.

[0100] Preferably, such aromatic ring is one or more benzene rings, naphthalene rings, anthracene rings, or pyrene rings; or a condensed ring of a benzene ring, a naphthalene ring, an anthracene ring, or a pyrene ring with a heterocycle or an aliphatic ring (such as a fluorene ring, a benzofluorene ring, a dibenzofluorene ring, an indole ring, a carbazole ring, or an indolocarbazole ring).

[0101] The aromatic ring may have any substituent, and from the viewpoint of polymerization reactivity, the substituent may contain the minimum necessary number of heteroatoms.In addition, the aromatic ring may have two or more aromatic rings connected by a linking group, and the linking group may contain the minimum necessary number of heteroatoms.Examples of the heteroatom include an oxygen atom, a nitrogen atom, a sulfur atom, etc.

[0102] The "aromatic ring" may contain at least one heteroatom selected from N, S and O on, within or between the rings.

[0103] Examples of heteroatoms that may be contained on the ring include nitrogen atoms contained in amino groups (e.g., propargylamino groups) and cyano groups; oxygen atoms contained in oxygen-containing substituents such as formyl groups, hydroxy groups, carboxy groups, alkoxy groups, alkenyloxy groups, alkynyloxy groups (e.g., propargyloxy groups), and aryloxy groups; and nitrogen atoms and oxygen atoms contained in nitro groups, which are oxygen-containing and nitrogen-containing substituents. Examples of heteroatoms that may be contained in the ring include oxygen atoms contained in furan and xanthene, nitrogen atoms contained in carbazole and pyrrole, and sulfur atoms contained in phenothiazine. Examples of heteroatoms that may be contained in the linking group of two or more aromatic rings include -NH-, -NHCO-, -O-, -COO-, -CO-, -S-, -SS-, and -SO ２ Examples of the aromatic ring include a nitrogen atom, an oxygen atom, and a sulfur atom. In this specification, "an atom constituting an aromatic ring" is synonymous with "an atom contained within the ring." "An atom bonded to an aromatic ring" refers to, for example, "an atom directly bonded to the ring among atoms or groups contained on the ring" and "an atom directly bonded to the ring among atoms contained between rings." For example, the atoms constituting a benzene ring are carbon atoms. For example, the atoms constituting a pyrrole ring are carbon atoms and nitrogen atoms. For example, the oxygen atom of a hydroxyl group in phenol is not an atom constituting an aromatic ring. For example, the oxygen atom of a hydroxyl group in phenol is an atom bonded to the benzene ring, and is an atom directly bonded to the benzene ring among groups contained on the benzene ring.

[0104] <<<A-2: Examples of Skeletons Constituting the Unit Structure (A)>>> The unit structure (A) has, for example, a skeleton having an aromatic ring.

[0105] The skeleton having an aromatic ring is preferably an aromatic amine skeleton, a nitrogen-containing aromatic heterocyclic skeleton, or a phenol skeleton.

[0106] The unit structure (A) is, for example, a residue obtained by removing two hydrogen atoms from a skeleton having an aromatic ring. The skeleton having an aromatic ring is derived, for example, from a compound having an aromatic ring when synthesizing the resin (A). The skeleton having an aromatic ring is, for example, a residue obtained by removing two hydrogen atoms from a compound having an aromatic ring when synthesizing the resin (A).

[0107] The skeleton having an aromatic ring may have a substituent.

[0108] <<<<<A-2-1: Aromatic Amine Skeleton>>>> The aromatic amine skeleton refers to a skeleton having an aromatic ring and a nitrogen atom that is bonded to the aromatic ring but is not part of the ring. Examples of the aromatic amine skeleton include skeletons represented by the following formulas (A-1a) to (A-1c). Note that, as described below, in the unit structure (A), the hydrogen atom of the NH group may be replaced with a substituent. (In formulas (A-1a) to (A-1c), Ar １１ R each independently represents a residue of an aromatic ring. １１ each independently represents a hydrogen atom or a residue of an aromatic ring.

[0109] Ar １１ and R １１ Examples of the aromatic ring in the residue of the aromatic ring include aromatic rings represented by the following formula (G1).

[0110] Examples of the skeleton represented by formula (A-1a) include the following skeletons:

[0111] Examples of the skeleton represented by formula (A-1b) include the following skeletons:

[0112] Examples of the skeleton represented by formula (A-1c) include the following skeletons:

[0113] <<<<<A-2-2: Nitrogen-Containing Aromatic Heterocyclic Skeleton>>>> The nitrogen-containing aromatic heterocyclic skeleton refers to a skeleton having an aromatic heterocycle having a nitrogen atom among the atoms constituting the heterocycle. Examples of the nitrogen-containing aromatic heterocycle include a pyrrole ring, an indole ring, a carbazole ring, a pyridine ring, an acridine ring, a phenoxazine ring, and a phenothiazine ring. Examples of the nitrogen-containing aromatic heterocyclic skeleton include a skeleton represented by the following formula (A-2a), (A-2b-1), (A-2b-2), (A-2c-1), (A-2c-2), (A-2c-3), or (A-2c-4). Note that, as described below, in the unit structure (A), the hydrogen atom of the NH group may be replaced by a substituent. (In the formula, Ar ２１ R each independently represents a residue of an aromatic ring. ２１ R each independently represents a hydrogen atom or a residue of an aromatic ring. ２２ each independently represents a hydrogen atom or a residue of an aromatic ring. ２２ may be joined together to form an unsaturated aliphatic ring. One of the unsaturated bonds in the unsaturated aliphatic ring refers to an unsaturated bond constituting a pyrrole ring. Each R independently represents a hydrogen atom, a residue of an aromatic ring, or a bond to 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 partial structure (In1) and the partial structure (In2), and the partial structure (Ca1) and the partial structure (Ca2), respectively, are bonded by two nitrogen atoms bonding together, or by two Ar ２１ or a nitrogen atom and Ar ２１ In formula (A-2b-2) and formula (A-2c-4), when L is a linking group, L is N or Ar ２１ is bonded to

[0114] Ar ２１ , R ２１ , R ２２ and the aromatic ring in the residue of the aromatic ring of R includes, for example, an aromatic ring represented by the following formula (G2).

[0115] Two adjacent R ２２ Examples of the unsaturated aliphatic ring formed by combining these include the following rings:

[0116] Examples of the linking group for L include a saturated hydrocarbon group having 1 to 5 carbon atoms and a valence of (n1+n2), and a residue obtained by removing (n1+n2) hydrogen atoms from an aromatic ring.

[0117] Examples of the skeleton represented by formula (A-2a) include the following skeletons:

[0118] Examples of the skeleton represented by formula (A-2b-1) include the following skeletons:

[0119] Examples of the skeleton represented by formula (A-2b-2) include the following skeletons:

[0120] Examples of the skeleton represented by formula (A-2c-1) include the following skeletons:

[0121] Examples of the skeleton represented by formula (A-2c-2) or formula (A-2c-3) include the following skeletons:

[0122] Examples of the skeleton represented by formula (A-2c-4) include the following skeletons:

[0123] <<<<A-2-3: Phenol Skeleton>>>> The phenol skeleton refers to a skeleton having an aromatic ring and a hydroxy group bonded to the aromatic ring. The number of hydroxy groups bonded to the aromatic ring of the phenol skeleton is not particularly limited and may be one or more. When there are more than one hydroxy groups, the number may be 2 to 10 or 2 to 8. When there are more than one hydroxy groups, the hydroxy groups may be bonded to the same aromatic ring (for example, a benzene ring) or to different aromatic rings. As will be described later, in the unit structure (A), the hydrogen atom of the hydroxy group bonded to the aromatic ring may be replaced with a substituent.

[0124] Examples of the phenol skeleton include skeletons represented by the following formula (A-4). (In the formula, n1, n2, n4, n5, n6, and n9 each independently represent an integer of 1 to 4. n3a, n3b, n7a, n7b, n8a, and n8b each independently represent an integer of 0 to 4, provided that the sum of n3a and n3b ​​is 1 or more, the sum of n7a and n7b is 1 or more, and the sum of n8a and n8b is 1 or more.)

[0125] Examples of the phenol skeleton include skeletons represented by the following formula (A-5a), formula (A-5b), formula (A-5c), and formula (A-5d). (In the formula, Ar ４１ each independently represents a residue of an aromatic ring. １ is -O-, -S-, -SO ２ - or an alkylene group which may be substituted with a halogen atom. ２ each independently represents a single bond, —O—, —S—, or —SO ２ Y represents - or an alkylene group which may be substituted with a halogen atom. １ represents a trivalent saturated hydrocarbon group. ２represents a tetravalent saturated hydrocarbon group. m1 and m2 each independently represent an integer of 0 to 3, provided that the sum of m1 and m2 is 1 or more. m3 to m5 each independently represent an integer of 0 to 3, provided that the sum of m3 to m5 is 1 or more. m6 to m8 each independently represent an integer of 0 to 3, provided that the sum of m6 to m8 is 1 or more. m9 to m12 each independently represent an integer of 0 to 3, provided that the sum of m9 to m12 is 1 or more.

[0126] Ar ４１ Examples of the aromatic ring in the residue of the aromatic ring include aromatic rings represented by the following formula (G3).

[0127] X １ , and X ２ The number of carbon atoms in the alkylene group which may be substituted with a halogen atom in the formula (I) is, for example, 1 to 20. The structure of the alkylene group may be, for example, linear, branched, cyclic, or a combination of two or more thereof. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0128] Y １ , and Y ２ The number of carbon atoms in the saturated hydrocarbon group in the formula (I) is, for example, 1 to 20. The structure of the saturated hydrocarbon group may be, for example, linear, branched, or cyclic, or a combination of two or more thereof.

[0129] Examples of the skeleton represented by formula (A-4) include the following skeletons:

[0130] Examples of the skeleton represented by formula (A-5a) include the following skeletons:

[0131] Examples of the skeleton represented by formula (A-5b) include the following skeletons:

[0132] Examples of the skeleton represented by formula (A-5c) include the following skeletons:

[0133] Examples of the skeleton represented by formula (A-5d) include the following skeletons:

[0134] Furthermore, the H of NH in the skeleton having an aromatic ring, the H of a hydroxy group bonded to the aromatic ring in the skeleton having an aromatic ring, and the hydrogen atom bonded to the aromatic ring in the skeleton having an aromatic ring may be substituted with a substituent. Examples of the substituent include the substituents (S) represented by the following formulae (S1) to (S7).

[0135] (In formulas (S1) to (S7), R ｓａ represents a monovalent non-aromatic hydrocarbon group having 1 to 10 carbon atoms. ｓｂ R each independently represents a single bond or a divalent non-aromatic hydrocarbon group having 1 to 10 carbon atoms. ｓｃ R each independently represents a divalent non-aromatic hydrocarbon group having 1 to 10 carbon atoms. ｓｄ ａｌｋｙｎｙｌ each independently represents an alkynyl group having 2 to 4 carbon atoms. ｓａ each independently represents a monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms. ｓｂ each independently represents a divalent aromatic hydrocarbon group having 6 to 20 carbon atoms. ｓａ and X ｓｂ each independently represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, or X ｓａ and X ｓｂ together with the carbon atom bonded to the hydroxy group, form a carbonyl group. n represents an integer of 0 to 5. * represents a bond.

[0136] <R ｓａ > R ｓａExamples of the monovalent non-aromatic hydrocarbon group having 1 to 10 carbon atoms in the formula (I) include an alkyl group having 1 to 10 carbon atoms and a monovalent unsaturated hydrocarbon group having 2 to 10 carbon atoms. The monovalent unsaturated hydrocarbon group having 2 to 10 carbon atoms has one or more carbon-carbon multiple bonds. When the monovalent unsaturated hydrocarbon group having 2 to 10 carbon atoms has two or more carbon-carbon multiple bonds, the two or more carbon-carbon multiple bonds may all be carbon-carbon double bonds, all may be carbon-carbon triple bonds, or may be a mixture of carbon-carbon double bonds and carbon-carbon triple bonds. The two or more carbon-carbon multiple bonds may or may not be conjugated.

[0137] <R ｓｂ , and R ｓｃ > R ｓｂ , and R ｓｃ In the formula, examples of the divalent non-aromatic hydrocarbon group having 1 to 10 carbon atoms include an alkylene group having 1 to 10 carbon atoms and a divalent unsaturated hydrocarbon group having 2 to 10 carbon atoms. The divalent unsaturated hydrocarbon group having 2 to 10 carbon atoms has one or more carbon-carbon multiple bonds. When the divalent unsaturated hydrocarbon group having 2 to 10 carbon atoms has two or more carbon-carbon multiple bonds, the two or more carbon-carbon multiple bonds may all be carbon-carbon double bonds, all may be carbon-carbon triple bonds, or may be a mixture of carbon-carbon double bonds and carbon-carbon triple bonds. The two or more carbon-carbon multiple bonds may or may not be conjugated. R ｓｂ , and R ｓｃ Examples of the group include the following groups: (* represents a bond.)

[0138] <R ｓｄ ａｌｋｙｎｙｌ > R ｓｄ ａｌｋｙｎｙｌ represents an alkynyl group having 2 to 4 carbon atoms. Examples of the alkynyl group having 2 to 4 carbon atoms include an ethenyl group, a 1-propynyl group, and a propargyl group (2-propynyl group).

[0139] <Ar ｓａ > Ar ｓａThe monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms in the formula (I) is a residue obtained by removing one hydrogen atom from an aromatic hydrocarbon having 6 to 20 carbon atoms. Examples of aromatic hydrocarbons having 6 to 20 carbon atoms include benzene, naphthalene, anthracene, phenanthrene, perinaphthane, pyrene, fluorene, and biphenyl.

[0140] <Ar ｓｂ > Ar ｓｂ The divalent aromatic hydrocarbon group having 6 to 20 carbon atoms in the formula (I) is a residue obtained by removing two hydrogen atoms from an aromatic hydrocarbon having 6 to 20 carbon atoms. Examples of aromatic hydrocarbons having 6 to 20 carbon atoms include benzene, naphthalene, anthracene, phenanthrene, pyrene, fluorene, and biphenyl.

[0141] <X ｓａ and X ｓｂ > X ｓａ and X ｓｂ In the formula (I), examples of the monovalent hydrocarbon group having 1 to 20 carbon atoms include a monovalent non-aromatic hydrocarbon group having 1 to 10 carbon atoms and a monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms. Examples of the monovalent non-aromatic hydrocarbon group having 1 to 10 carbon atoms include an alkyl group having 1 to 10 carbon atoms. A monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms is a residue obtained by removing one hydrogen atom from an aromatic hydrocarbon having 6 to 20 carbon atoms. Examples of aromatic hydrocarbons having 6 to 20 carbon atoms include benzene, naphthalene, anthracene, phenanthrene, perinaphthane, pyrene, fluorene, and biphenyl.

[0142] Examples of the substituent represented by formula (S1) include the following groups. (* represents a bond.)

[0143] Examples of the substituent represented by formula (S2) include the following groups. (* represents a bond.)

[0144] Examples of the substituent represented by formula (S3) include the following groups. (* represents a bond.)

[0145] Examples of the substituent represented by formula (S4) include the following groups. (* represents a bond.)

[0146] Examples of the substituent represented by formula (S5) include the following groups. (* represents a bond.)

[0147] Examples of the substituent represented by formula (S6) include the following groups. (* represents a bond.)

[0148] Examples of the substituent represented by formula (S7) include the following groups. (* represents a bond.)

[0149] Examples of other substituents include the following groups: (* represents a bond.)

[0150] The unit structure (A) is preferably at least one selected from the following: Note that the positions of the two bonds shown in each unit structure shown below are shown merely for convenience, and each bond can extend from any possible carbon atom, and the positions are not limited thereto.

[0151] (Examples of unit structures composed of aromatic amine skeletons) -NH- can also have a structure in which the hydrogen atom on the N is substituted.

[0152]

[0153] (Examples of unit structures composed of nitrogen-containing aromatic heterocyclic skeletons)

[0154] (Example of a unit structure composed of a phenol skeleton)

[0155] <<<B-1: Unit Structure (B)>>> The unit structure (B) has one or more carbon atoms. The unit structure (B) is, for example, a unit structure derived from an aldehyde compound or an aldehyde equivalent. The aldehyde equivalent is an organic compound capable of forming a covalent bond with an aromatic ring, and is an organic compound having a ketone group; an acetal group; a ketal group; a hydroxyl group or an alkoxy group bonded to a secondary or tertiary carbon atom; a hydroxyl group, an alkoxy group, or a halo group bonded to the α-position carbon atom of an alkylaryl group; or a carbon-carbon unsaturated bond. The unit structure (B) is one or more unit structures containing a linking carbon atom bonded to an aromatic ring in the unit structure (A) [see (I-1) above], and includes, for example, a structure represented by the formula (B1), (B2), or (B3) shown below. The unit structure (B) can link two unit structures (A) by forming a covalent bond with the unit structure (A).

[0156] <<<<B-2: Formula (B1)>>>> The unit structure (B) includes, for example, a structure represented by the following formula (B1): The unit structure (B) may 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 a substituent, a heterocyclic ring having 3 to 30 carbon atoms which may have a substituent, or a linear, branched, or cyclic alkyl group having 10 or less carbon atoms which may have a substituent. R and R' may form a structure having a ring structure together with the carbon atom to which they are bonded. * represents a bond.

[0157] Examples of the substituent include a hydroxy group, a carboxy group, a formyl group, a nitro group, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, a cyano group, and a group in which the H of a hydroxy group has been substituted with the above-mentioned substituent (S).

[0158] Furthermore, the two bonds in formula (B1) can be covalently bonded to the aromatic rings in the two structural units (A), respectively.

[0159] In the definition of R and R′ in formula (B1), examples of the “aromatic ring” include aromatic hydrocarbon rings such as benzene, indene, naphthalene, azulene, styrene, toluene, xylene, mesitylene, cumene, anthracene, phenanthrene, triphenylene, benzanthracene, pyrene, chrysene, fluorene, biphenyl, corannulene, perylene, fluoranthene, benzo[k]fluoranthene, benzo[b]fluoranthene, benzo[ghi]perylene, coronene, dibenzo[g,p]chrysene, acenaphthylene, acenaphthene, naphthacene, pentacene, and cyclooctatetraene, more typically aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and pyrene; furan, pyran, pyridine, pyrimidine, Examples of aromatic heterocycles include pyrazine, thiophene, pyrrole, N-alkylpyrrole, N-arylpyrrole, imidazole, pyridine, pyrimidine, pyrazine, triazine, thiazole, indole, phenylindole, bisindolefluorene, bisindolebenzofluorene, bisindoledibenzofluorene, purine, quinoline, isoquinoline, chromene, thianthrene, phenothiazine, phenoxazine, xanthene, acridine, phenazine, carbazole, and indolocarbazole, and more typically include, but are not limited to, furan, thiophene, pyrrole, indole, phenylindole, bisindolefluorene, phenothiazine, carbazole, and indolocarbazole. Furthermore, the term "aromatic ring" also includes organic groups having one or more fused aromatic rings (such as benzene, naphthalene, anthracene, and pyrene) with one or more fused aliphatic or heterocyclic rings. Examples of the aliphatic ring include cyclobutane, cyclobutene, cyclopentane, cyclopentene, cyclohexane, cyclohexene, methylcyclohexane, methylcyclohexene, cycloheptane, and cycloheptene, and examples of the heterocycle include furan, thiophene, pyrrole, imidazole, pyran, pyridine, pyrimidine, pyrazine, pyrrolidine, piperidine, piperazine, and morpholine. The "aromatic ring" may be an organic group having a structure in which two or more aromatic rings are linked by a divalent linking group.Examples of the divalent linking group include an alkylene group, an arylene group, -NH-, -NHCO-, -O-, -COO-, -CO-, -S-, -SS-, and -SO. ２ -, etc. The divalent linking group may also be a divalent group obtained by removing one hydrogen atom from any of the substituents of the aromatic ring described above. The "aromatic ring" may have a substituent such as a halogen atom, an alkyl group, a hydroxyl group, or a carboxy group.

[0160] In the definitions of R and R' in formula (B1), the term "heterocycle" encompasses both aliphatic heterocycles and aromatic heterocycles, and is a concept that encompasses not only monocyclic (heteromonocyclic) but also polycyclic (heteropolycyclic) cycles. In the case of a polycyclic cycle, at least one monocyclic cycle is a heteromonocyclic cycle, but the remaining monocyclic cycles may be aromatic hydrocarbon monocyclic cycles or alicyclic monocyclic cycles. For the aromatic heterocycle, the examples of the "aromatic ring" mentioned above can be referred to. As with the "aromatic ring", it may have a substituent.

[0161] In the definition of R and R′ in formula (B1), examples of the “alkyl group” include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, a cyclopropyl group, an n-butyl group, an i-butyl group, an s-butyl group, a t-butyl group, a cyclobutyl group, a 1-methyl-cyclopropyl group, a 2-methyl-cyclopropyl group, an n-pentyl group, a 1-methyl-n-butyl group, a 2-methyl-n-butyl group, a 3-methyl-n-butyl group, a 1,1-dimethyl-n-propyl group, a 1,2-dimethyl-n-propyl group, a 2,2-dimethyl-n-propyl group, a 1- Ethyl-n-propyl group, cyclopentyl group, 1-methyl-cyclobutyl group, 2-methyl-cyclobutyl group, 3-methyl-cyclobutyl group, 1,2-dimethyl-cyclopropyl group, 2,3-dimethyl-cyclopropyl group, 1-ethyl-cyclopropyl group, 2-ethyl-cyclopropyl group, n-hexyl group, 1-methyl-n-pentyl group, 2-methyl-n-pentyl group, 3-methyl-n-pentyl group, 4-methyl-n-pentyl group, 1,1-dimethyl-n-butyl group, 1,2-dimethyl-n-butyl group, 1,3-dimethyl-n-butyl group ethyl 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 cyclobutyl group, 3-ethylcyclobutyl group, 1,2-dimethylcyclobutyl group, 1,3-dimethylcyclobutyl group, 2,2-dimethylcyclobutyl group, 2,3-dimethylcyclobutyl group, 2,4-dimethylcyclobutyl group, 3,3-dimethylcyclobutyl group, 1-n-propylcyclopropyl group, 2-n-propylcyclopropyl group, 1-i-propylcyclopropyl group, 2-i-propylcyclopropyl group, 1,2,2-trimethylcyclopropyl group, 1,2,3-trimethylcyclopropyl group, 2,2,Examples of the cyclopropyl group include a 3-trimethyl-cyclopropyl group, a 1-ethyl-2-methyl-cyclopropyl group, a 2-ethyl-1-methyl-cyclopropyl group, a 2-ethyl-2-methyl-cyclopropyl group, a 2-ethyl-3-methyl-cyclopropyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, and an n-decyl group.

[0162] Preferably, R and R' are each independently phenyl, naphthalenyl, anthracenyl, phenanthrenyl, naphthacenyl, or pyrenyl.

[0163] Examples of the ring structure formed by R and R' together with the carbon atoms to which they are bonded include structures represented by the following formulas. (In the formula, each Ar independently represents a residue of an aromatic ring. The carbon atom marked with * is the carbon atom bonded to R and R′ in formula (B1).)

[0164] Examples of the aromatic ring of Ar include aromatic rings represented by formula (G1).

[0165] The unit structure (B) containing the structure represented by formula (B1) is derived from, for example, an aldehyde compound or a ketone compound. Examples of the aldehyde compound include the compound represented by the following formula (B-1a). Examples of the ketone compound include the compound represented by the following formula (B-1b). (In formula (B-1a) and formula (B-1b), R and R' have the same meanings as R and R' in formula (B1), respectively, with the proviso that R and R' are other than a hydrogen atom. In formula (B-1b), R and R' may form a structure having a ring structure together with the carbon atom to which they are bonded.)

[0166] For example, in obtaining resin (A-5), the carbonyl groups in formula (B-1a) and formula (B-1b) are converted to *-C-* in formula (B1).

[0167] Some specific examples of the unit structure (B) containing the structure represented by formula (B1) are as follows. * basically indicates the bonding site with the unit structure (A). Needless to say, the structure may contain the exemplified structure as a part of the whole.

[0168] The content of the resin (A) is, for example, preferably 50 to 99.9 mass %, more preferably 60 to 99.9 mass %, and even more preferably 70 to 99.5 mass %, based on the total solid content of the composition for forming a resist underlayer film. Here, the "total solid content of the composition for forming a resist underlayer film" refers to the total mass of the components of the composition for forming a resist underlayer film excluding the solvent (B), which will be described later.

[0169] <Solvent (B)> The solvent (B) is not particularly limited and may be water or an organic solvent. Examples of the organic solvent include alkylene glycol monoalkyl ethers and monocarboxylic acid esters of alkylene glycol monoalkyl ethers.

[0170] Examples of the alkylene group of the alkylene glycol monoalkyl ether include alkylene groups having 2 to 4 carbon atoms. Examples of the alkyl group of the alkylene glycol monoalkyl ether include alkyl groups having 1 to 4 carbon atoms. Examples of the number of carbon atoms of the alkylene glycol monoalkyl ether include 3 to 8. Examples of the alkylene glycol monoalkyl ether include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, and propylene glycol monoethyl ether.

[0171] Examples of the alkylene group of the monocarboxylic acid ester of alkylene glycol monoalkyl ether include alkylene groups having 2 to 4 carbon atoms. Examples of the alkyl group of the monocarboxylic acid ester of alkylene glycol monoalkyl ether include alkyl groups having 1 to 4 carbon atoms. Examples of the monocarboxylic acid of the monocarboxylic acid ester of alkylene glycol monoalkyl ether include saturated monocarboxylic acids having 2 to 4 carbon atoms. Examples of saturated monocarboxylic acids having 2 to 4 carbon atoms include acetic acid, propionic acid, and butyric acid. Examples of the number of carbon atoms of the monocarboxylic acid ester of alkylene glycol monoalkyl ether include those having 5 to 10 carbon atoms. Examples of the monocarboxylic acid ester of alkylene glycol monoalkyl ether include methyl cellosolve acetate, ethyl cellosolve acetate, propylene glycol monomethyl ether acetate, and propylene glycol propyl ether acetate.

[0172] Other organic solvents include, for example, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, cycloheptanone, 4-methyl-2-pentanol, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate, ethyl ethoxyacetate, 2-hydroxyethyl acetate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, 2-heptanone, methoxycyclopentane, anisole, γ-butyrolactone, N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide.

[0173] Among these solvents (B), alkylene glycol monoalkyl ethers and monocarboxylic acid esters of alkylene glycol monoalkyl ethers are preferred.

[0174] These solvents (B) may be used alone or in combination of two or more.

[0175] The mass proportion of the organic solvent in the solvent (B) is not particularly limited, but is preferably 50 mass % to 100 mass %.

[0176] The content of the solvent (B) in the composition for forming a resist underlayer film is not particularly limited, but is preferably 50% by mass to 99.99% by mass, more preferably 75% by mass to 99.95% by mass, and particularly preferably 90% by mass to 99.9% by mass.

[0177] <Surfactant (C)> The surfactant (C) is a copolymer containing structural units derived from monomers represented by the following formulas (I), (II), and (III). It is also called a surface conditioner. The surfactant (C) is a non-fluorine-based organic surfactant that does not contain fluorine. Since the composition for forming a resist underlayer film of this embodiment contains the surfactant (C), it does not fall under the category of PFAS and has good planarization properties. In addition, it is desirable from the viewpoint of dry etching selectivity. (In formula (I), R １ represents a hydrogen atom or a methyl group, R ２ represents an alkylene group having 1 to 4 carbon atoms, R ３ represents an aliphatic hydrocarbon group having 10 to 30 carbon atoms. ４ and R ５ may be the same or different and represent a hydrogen atom or a methyl group, AO represents an oxyalkylene group having 2 to 4 carbon atoms, and n is the average number of moles added and is 1 to 200. In formula (III), R ６ is an aliphatic hydrocarbon group having 1 to 12 carbon atoms.

[0178] The monomer represented by formula (I) is, for example, 2-hexadecanamidoethyl acrylate (R １ is a hydrogen atom, R ２ is an ethylene group, R ３ is a pentadecyl group), 2-octadecaneamidoethyl acrylate (a compound in which R １ is a hydrogen atom, R ２is an ethylene group, R ３ is a heptadecyl group).

[0179] The monomer represented by formula (II) is, for example, α-methacryloyl-ω-methoxypoly(oxyethylene) (R ４ and R ５ is a methyl group, AO is an oxyethylene group, and n is a compound of 2 to 20.

[0180] Examples of the monomer represented by formula (III) include N-cyclohexylmaleimide (R ６ is a cyclohexyl group).

[0181] The surfactant (C) may be a copolymer containing structural units derived from two or more types of monomers represented by formula (I).

[0182] Specific examples of the surfactant (C) include copolymers containing a structural unit represented by the following formula (IV). (In formula (IV), a+b+c+d=1, a, b, c, and d are each independently a number greater than 0 and less than 1 that represents a mass ratio, and n is a number from 2 to 20 that represents the average number of moles added.)

[0183] In formula (IV), a is, for example, preferably 0.25 to 0.45. In formula (IV), b is, for example, preferably 0.05 to 0.25. In formula (IV), c is, for example, preferably 0.40 to 0.70. In formula (IV), d is, for example, preferably 0.001 to 0.01. a, b, c, and d in formula (IV) can be determined by NMR measurement or the like.

[0184] A copolymer containing a structural unit represented by formula (IV) can be obtained by mixing raw material monomers in a predetermined weight ratio in a solvent and reacting them at a desired temperature for a desired time. The copolymer containing a structural unit represented by formula (IV) may be a block copolymer or a random copolymer. Furthermore, the copolymer containing a structural unit represented by formula (IV) may contain other structural units.

[0185] Compared to fluorine-based surfactants and silicone-based surfactants, general organic surfactants are inferior in leveling properties (flattening properties during film formation) and removability in an edge bead removal process (hereinafter abbreviated as "EBR") for removing unnecessary photoresist residues and contaminants applied to the edge or rear surface of a substrate. However, the surfactant (C) of this embodiment is a copolymer containing structural units derived from a specific monomer, and therefore has excellent leveling properties and removability in EBR.

[0186] The content of the surfactant (C) is usually 3.0% by mass or less, preferably 2.0% by mass or less, based on the solid content of the resin (A). The lower limit of the content of the surfactant (C) is, for example, 0.1% by mass, based on the solid content of the resin (A). The surfactant (C) may be added alone or in combination of two or more.

[0187] <Crosslinking Agent (D)> The crosslinking agent (D) is not particularly limited. The crosslinking agent (D) has a structure different from that of the compound (A) and the polymer (C).

[0188] The crosslinking agent (D) is preferably an aminoplast crosslinking agent or a phenoplast crosslinking agent. The aminoplast crosslinking agent is an addition condensation product of a compound having an amino group, such as melamine or guanamine, with formaldehyde. The phenoplast crosslinking agent is an addition condensation product of a compound having a phenolic hydroxy group with formaldehyde.

[0189] Examples of the crosslinking agent (D) include compounds having two or more of the following structures: (In the structure, R １０１ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an alkoxyalkyl group having 2 to 6 carbon atoms. * represents a bond.) The bond is bonded to, for example, a nitrogen atom or a carbon atom constituting an aromatic hydrocarbon ring.

[0190] R １０１ is preferably a hydrogen atom, a methyl group, an ethyl group or a group represented by the following structure. (In the structure, R １０２represents a hydrogen atom, a methyl group, or an ethyl group. * represents a bond.

[0191] The crosslinking agent (D) is preferably a melamine compound, a guanamine compound, a glycoluril compound, a urea compound, or a compound having a phenolic hydroxy group, which may be used alone or in combination of two or more.

[0192] Examples of the melamine compound include hexamethylol melamine, hexamethoxymethyl melamine, a compound in which 1 to 6 methylol groups of hexamethylol melamine have been methoxymethylated, or a mixture thereof, hexamethoxyethyl melamine, hexaacyloxymethyl melamine, a compound in which 1 to 6 methylol groups of hexamethylol melamine have been acyloxymethylated, or a mixture thereof.

[0193] Examples of the guanamine compound include tetramethylolguanamine, tetramethoxymethylguanamine, a compound in which one to four methylol groups of tetramethylolguanamine are methoxymethylated, or a mixture thereof; tetramethoxyethylguanamine, tetraacyloxyguanamine, a compound in which one to four methylol groups of tetramethylolguanamine are acyloxymethylated, or a mixture thereof; and the like.

[0194] Examples of glycoluril compounds include tetramethylol glycoluril, tetramethoxy glycoluril, tetramethoxymethyl glycoluril, compounds in which one to four methylol groups of tetramethylol glycoluril are methoxymethylated or mixtures thereof, and compounds in which one to four methylol groups of tetramethylol glycoluril are acyloxymethylated or mixtures thereof.

[0195] The glycoluril compound may be, for example, a glycoluril derivative represented by the following formula (1E). (In formula (1E), four R １ each independently represents a methyl group or an ethyl group, R ２ and R ３each independently represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group.

[0196] Examples of the glycoluril derivative represented by the formula (1E) include compounds represented by the following formulas (1E-1) to (1E-6).

[0197] The glycoluril derivative represented by formula (1E) can be obtained, for example, by reacting a glycoluril derivative represented by the following formula (2E) with at least one compound represented by the following formula (3d).

[0198] (In formula (2E), R ２ and R ３ each independently represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group; R ４ each independently represents an alkyl group having 1 to 4 carbon atoms.

[0199] (In formula (3d), R １ represents a methyl group or an ethyl group.

[0200] Examples of glycoluril derivatives represented by formula (2E) include compounds represented by formulas (2E-1) to (2E-4) below. Furthermore, examples of compounds represented by formula (3d) include compounds represented by formulas (3d-1) and (3d-2) below.

[0201] Examples of the urea compound include tetramethylol urea, tetramethoxymethyl urea, tetramethylol urea compounds in which one to four methylol groups are methoxymethylated, or mixtures thereof, and tetramethoxyethyl urea.

[0202] Examples of the compound having a phenolic hydroxy group include compounds represented by the following formula (G-1) or (G-2). (In formula (G-1) and formula (G-2), Q １ represents a single bond or a monovalent organic group. １ and R ４R represents an alkyl group having 2 to 10 carbon atoms, or an alkyl group having 2 to 10 carbon atoms and an alkoxy group having 1 to 10 carbon atoms. ２ and R ５ R represents a hydrogen atom or a methyl group. ３ and R ６ n represents an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 40 carbon atoms. １ is 1≦n １ an integer ≦3, n ２ is 2≦n ２ an integer ≦5, n ３ is 0≦n ３ an integer ≦3, n ４ is 0≦n ４ an integer ≦3, 3≦(n １ +n ２ +n ３ +n ４ ) represents an integer ≦6. ５ is 1≦n ５ an integer ≦3, n ６ is 1≦n ６ an integer ≦4, n ７ is 0≦n ７ an integer ≦3, n ８ is 0≦n ８ an integer ≦3, 2≦(n ５ +n ６ +n ７ +n ８ ) represents an integer of ≦5. m1 represents an integer of 2 to 10.

[0203] Examples of compounds having a phenolic hydroxy group include compounds represented by the following formula (G-3) or formula (G-4): The compound represented by formula (G-1) or formula (G-2) may be obtained by reacting a compound represented by the following formula (G-3) or formula (G-4) with a hydroxyl group-containing ether compound or an alcohol having 2 to 10 carbon atoms. (In formula (G-3) and formula (G-4), Q ２ represents a single bond or a divalent organic group. ８ , R ９ , R １１ and R １２ R represents a hydrogen atom or a methyl group.７ and R １０ n represents an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 40 carbon atoms. ９ is 1≦n ９ an integer ≦3, n １０ is 2≦n １０ an integer ≦5, n １１ is 0≦n １１ an integer ≦3, n １２ is 0≦n １２ an integer ≦3, 3≦(n ９ +n １０ +n １１ +n １２ ) represents an integer ≦6. １３ is 1≦n １３ an integer ≦3, n １４ is 1≦n １４ an integer ≦4, n １５ is 0≦n １５ an integer ≦3, n １６ is 0≦n １６ an integer ≦3, 2≦(n １３ +n １４ +n １５ +n １６ ) represents an integer of ≦5. m2 represents an integer of 2 to 10. ２ In the above, the m2-valent organic group includes, for example, an m2-valent organic group having 1 to 4 carbon atoms.

[0204] Examples of the compound represented by formula (G-1) or formula (G-2) include the following compounds:

[0205] Examples of the compound represented by formula (G-3) or formula (G-4) include the following compounds: The above compound is available as a product of Asahi Organic Chemicals Co., Ltd. and Honshu Chemical Industry Co., Ltd. An example of the product is TMOM-BP, a product name of Asahi Organic Chemicals Co., Ltd.

[0206] Among these, glycoluril compounds are preferred, specifically tetramethylol glycoluril, tetramethoxy glycoluril, tetramethoxymethyl glycoluril, tetramethylol glycoluril compounds in which one to four methylol groups have been methoxymethylated or mixtures thereof, and tetramethylol glycoluril compounds in which one to four methylol groups have been acyloxymethylated or mixtures thereof, with tetramethoxymethyl glycoluril being more preferred.

[0207] The molecular weight of the crosslinking agent (D) is not particularly limited, but is preferably 500 or less.

[0208] The content of the crosslinking agent (D) in the composition for forming a resist underlayer film is not particularly limited, but is, for example, 1% by mass to 70% by mass, and preferably 5% by mass to 60% by mass, relative to the resin (A).

[0209] <Curing Catalyst (E)> The curing catalyst (E) contained as an optional component in the composition for forming a resist underlayer film may be either a thermal acid generator or a photoacid generator, but it is preferable to use a thermal acid generator. Examples of the thermal acid generator include sulfonic acid compounds or carboxylic acid compounds such as p-toluenesulfonic acid, trifluoromethanesulfonic acid, pyridinium-p-toluenesulfonate (pyridinium-p-toluenesulfonic acid), pyridinium phenolsulfonic acid, pyridinium-p-hydroxybenzenesulfonic acid (pyridinium p-phenolsulfonate salt), pyridinium-trifluoromethanesulfonic acid, salicylic acid, camphorsulfonic acid, 5-sulfosalicylic acid, 4-chlorobenzenesulfonic acid, 4-hydroxybenzenesulfonic acid, benzenedisulfonic acid, 1-naphthalenesulfonic acid, citric acid, benzoic acid, hydroxybenzoic acid, N-methylmorpholine-p-toluenesulfonic acid, N-methylmorpholine-p-hydroxybenzenesulfonic acid, and N-methylmorpholine-5-sulfosalicylic acid.

[0210] Examples of the photoacid generator include an onium salt compound, a sulfonimide compound, and a disulfonyldiazomethane compound.

[0211] Examples of the onium salt compound include iodonium salt compounds such as diphenyliodonium hexafluorophosphate, diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoro-normal butanesulfonate, diphenyliodonium perfluoro-normal octanesulfonate, diphenyliodonium camphorsulfonate, bis(4-tert-butylphenyl)iodonium camphorsulfonate, and bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate; and sulfonium salt compounds such as triphenylsulfonium hexafluoroantimonate, triphenylsulfonium nonafluoro-normal butanesulfonate, triphenylsulfonium camphorsulfonate, and triphenylsulfonium trifluoromethanesulfonate.

[0212] Examples of the sulfonimide compound include N-(trifluoromethanesulfonyloxy)succinimide, N-(nonafluoronormalbutanesulfonyloxy)succinimide, N-(camphorsulfonyloxy)succinimide, and N-(trifluoromethanesulfonyloxy)naphthalimide.

[0213] Examples of the disulfonyldiazomethane compound include bis(trifluoromethylsulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, bis(phenylsulfonyl)diazomethane, bis(p-toluenesulfonyl)diazomethane, bis(2,4-dimethylbenzenesulfonyl)diazomethane, and methylsulfonyl-p-toluenesulfonyldiazomethane.

[0214] The curing catalyst (E) may be used alone or in combination of two or more.

[0215] When the curing catalyst (E) is used, the content of the curing catalyst (E) relative to the crosslinking agent (D) is, for example, 0.1% by mass to 50% by mass, and preferably 1% by mass to 30% by mass.

[0216] The solid content of the composition for forming a resist underlayer film of the present invention, that is, the content of components excluding the solvent (B), is, for example, 0.01% by mass to 10% by mass.

[0217] (Resist Underlayer Film) The resist underlayer of the present invention is a cured product of the composition for forming a resist underlayer film described above. The resist underlayer film can be produced, for example, by applying the composition for forming a resist underlayer film described above onto a semiconductor substrate and baking it.

[0218] Examples of the semiconductor substrate onto which the resist underlayer film forming composition is applied include silicon wafers, germanium wafers, and wafers of compound semiconductors such as gallium arsenide, indium phosphide, gallium nitride, indium nitride, and aluminum nitride.

[0219] When a semiconductor substrate having an inorganic film formed on its surface is used, the inorganic film can be formed by, for example, ALD (atomic layer deposition), CVD (chemical vapor deposition), reactive sputtering, ion plating, vacuum deposition, or spin coating (spin-on glass: SOG). Examples of the inorganic film include a polysilicon film, a silicon oxide film, a silicon nitride film, a BPSG (Boro-Phospho Silicate Glass) film, a titanium nitride film, a titanium nitride oxide film, a tungsten film, a gallium nitride film, or a gallium arsenide film.

[0220] The resist underlayer film-forming composition of the present invention is applied to such a semiconductor substrate by a suitable application method such as a spinner or coater. The composition is then baked using a heating means such as a hot plate to form a resist underlayer film. The baking conditions are appropriately selected from a baking temperature of 100°C to 400°C and a baking time of 0.3 to 60 minutes. A baking temperature of 120°C to 350°C and a baking time of 0.5 to 30 minutes are preferred, and a baking temperature of 150°C to 300°C and a baking time of 0.8 to 10 minutes are more preferred.

[0221] The thickness of the resist underlayer film may be, for example, 0.001 μm (1 nm) to 10 μm, 0.002 μm (2 nm) to 1 μm, 0.005 μm (5 nm) to 0.5 μm (500 nm), 0.001 μm (1 nm) to 0.05 μm (50 nm), 0.002 μm (2 nm) to 0.05 μm (50 nm), 0.003 μm (3 nm) to 0.05 μm (50 nm), 0.004 μm (4 nm) to 0.05 μm (50 nm), 0.005 μm (5 nm) to 0.05 μm (5 0 nm), 0.003 μm (3 nm) to 0.03 μm (30 nm), 0.003 μm (3 nm) to 0.02 μm (20 nm), 0.005 μm (5 nm) to 0.02 μm (20 nm), 0.005 μm (5 nm) to 0.02 μm (20 nm), 0.003 μm (3 nm) to 0.01 μm (10 nm), 0.005 μm (5 nm) to 0.01 μm (10 nm), 0.003 μm (3 nm) to 0.006 μm (6 nm), or 0.005 μm (5 nm).

[0222] The method for measuring the film thickness of the resist underlayer film in this specification is as follows: Name of measuring device: Ellipso film thickness measuring device RE-3100 (SCREEN Corporation) SWE (single wavelength ellipsometer) mode Arithmetic mean of 8 points (for example, measuring 8 points at 1 cm intervals in the X direction of the wafer)

[0223] (Laminate) The laminate of the present invention includes a semiconductor substrate and the resist underlayer film of the present invention. Examples of the semiconductor substrate include the semiconductor substrates described above. The resist underlayer film is disposed on the semiconductor substrate, for example.

[0224] (Method for manufacturing a semiconductor element, method for forming a pattern) The method for manufacturing a semiconductor element of the present invention includes at least the following steps: forming a resist underlayer film on a semiconductor substrate using the composition for forming a resist underlayer film of the present invention, and forming a resist film on the resist underlayer film.

[0225] The pattern forming method of the present invention includes at least the following steps: forming a resist underlayer film on a semiconductor substrate using the composition for forming a resist underlayer film of the present invention, forming a resist film on the resist underlayer film, irradiating the resist film with light or an electron beam and then developing the resist film to obtain a resist pattern, and etching the resist underlayer film using the resist pattern as a mask.

[0226] Typically, a resist layer is formed on the resist underlayer film. The film thickness of the resist layer is, for example, 3,000 nm or less, 2,000 nm or less, 1,800 nm or less, 1,500 nm or less, or 1,000 nm or less. The lower limit is 100 nm, 80 nm, 50 nm, 30 nm, 20 nm, or 10 nm.

[0227] The resist film formed on the resist underlayer film by a known method (e.g., coating and baking a resist composition) is not particularly limited as long as it is responsive to light or electron beam (EB) irradiation. Both negative and positive photoresists can be used. In this specification, resists responsive to EB are also referred to as photoresists. Examples of photoresists include positive photoresists composed of a novolak resin and a 1,2-naphthoquinone diazide sulfonic acid ester; chemically amplified photoresists composed of a binder having a group that decomposes in the presence of an acid to increase the alkaline dissolution rate and a photoacid generator; chemically amplified photoresists composed of a low-molecular-weight compound that decomposes in the presence of an acid to increase the alkaline dissolution rate of the photoresist, an alkali-soluble binder, and a photoacid generator; chemically amplified photoresists composed of a binder having a group that decomposes in the presence of an acid to increase the alkaline dissolution rate, a low-molecular-weight compound that decomposes in the presence of an acid to increase the alkaline dissolution rate of the photoresist, and a photoacid generator; and resists containing metal elements. Examples of such photoresists include V146G (trade name) manufactured by JSR Corporation, APEX-E (trade name) manufactured by Shipley Co., Ltd., PAR710 (trade name) manufactured by Sumitomo Chemical Co., Ltd., and AR2772 and SEPR430 (trade names) manufactured by Shin-Etsu Chemical Co., Ltd. Further examples include fluorine-containing polymer photoresists such as those described in Proc. SPIE, Vol. 3999, 330-334 (2000), Proc. SPIE, Vol. 3999, 357-364 (2000), and Proc. SPIE, Vol. 3999, 365-374 (2000).

[0228] Also, WO2019 / 188595, WO2019 / 187881, WO2019 / 187803, WO2019 / 167737, WO2019 / 167725, WO2019 / 187445, WO2019 / 167419, WO2019 / 123842, WO2019 / 054282, WO2019 / 058945, WO2019 / 058890, WO2019 / 039290, WO2019 / 044259, WO2019 / 044231, WO2019 / 026549, WO2018 / 193954, WO201 9 / 172054, WO2019 / 021975, WO2018 / 230334, WO2018 / 194123, JP 2018-180525, WO2018 / 190088, JP 2018-070596, JP 2018-028090, JP 2016-153409, JP 2016-130240, JP 2016-108325, JP 2016-047920, JP 2016-035570, JP 2016-035567, JP 2016-035565, JP 2019-101417, JP 2019-117373, JP 2019-052294, JP 2019-008280, JP 2019-008279, JP 2019-003176, JP 2019-003175, JP 2018-197853, JP 2019-191298, JP 2019-061217, JP 2018-045152, JP 2018-022039, JP 2016-090441, JP 2015-10878, JP 2012-168279, JP 2012-022261, JP 2012-022258, JP 2011-043749, JP 2010-18 1857, JP 2010-128369, WO2018 / 031896, JP 2019-113855, WO2017 / 156388, WO2017 / 066319, JP 2018-41099, WO2016 / 065120, WO2015 / 026482, JP 2016-29498, JP 2011-253185, etc., radiation-sensitive resin compositions, so-called resist compositions such as high-resolution patterning compositions based on organometallic solutions, and metal-containing resist compositions can be used, but are not limited to these.

[0229] Examples of the resist composition include the following compositions.

[0230] An actinic ray-sensitive or radiation-sensitive resin composition comprising: Resin A having a repeating unit having an acid-decomposable group in which a polar group is protected with a protecting group that is cleaved by the action of an acid; and a compound represented by the following general formula (121):

[0231] In the general formula (121), m represents an integer of 1 to 6. １ and R ２ each independently represents a fluorine atom or a perfluoroalkyl group. １ is -O-, -S-, -COO-, -SO ２ - or -SO ３ - represents. ２ represents an alkylene group which may have a substituent or a single bond. １ represents a cyclic organic group which may have a substituent. ＋ represents a cation.

[0232] A metal-containing film-forming composition for extreme ultraviolet or electron beam lithography, comprising a compound having a metal-oxygen covalent bond and a solvent, wherein the metal element constituting the compound belongs to Periods 3 to 7 of Groups 3 to 15 of the periodic table.

[0233] A radiation-sensitive resin composition comprising: a polymer having a first structural unit represented by the following formula (31) and a second structural unit represented by the following formula (32) containing an acid-dissociable group; and an acid generator.

[0234] In formula (31), Ar is a group obtained by removing (n+1) hydrogen atoms from an arene having 6 to 20 carbon atoms. １ is a hydroxy group, a sulfanyl group, or a monovalent organic group having 1 to 20 carbon atoms. n is an integer of 0 to 11. When n is 2 or more, multiple R １ are the same or different. ２ is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. ３ is a monovalent group having 1 to 20 carbon atoms containing the above acid-dissociable group. Z is a single bond, an oxygen atom, or a sulfur atom. R ４is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0235] A resist composition comprising: a resin (A1) containing a structural unit having a cyclic carbonate structure, a structural unit represented by the following formula, and a structural unit having an acid labile group; and an acid generator.

[0236] [In the formula, R ２ represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom; X １ represents a single bond, —CO—O—*, or —CO—NR ４ -*, * represents a bond to -Ar, R ４ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have one or more groups selected from the group consisting of a hydroxy group and a carboxy group.]

[0237] Examples of the resist film include the following.

[0238] A resist film comprising a base resin comprising a repeating unit represented by the following formula (a1) and / or a repeating unit represented by the following formula (a2), and a repeating unit that generates an acid bonded to a polymer main chain upon exposure:

[0239] (In formula (a1) and formula (a2), R Ａ are each independently a hydrogen atom or a methyl group. １ and R ２ are each independently a tertiary alkyl group having 4 to 6 carbon atoms. ３ are each independently a fluorine atom or a methyl group, and m is an integer of 0 to 4. １ X is a single bond, a phenylene group, or a naphthylene group, or a linking group having 1 to 12 carbon atoms and containing at least one selected from an ester bond, a lactone ring, a phenylene group, and a naphthylene group. ２ is a single bond, an ester bond, or an amide bond.

[0240] Examples of resist materials include the following:

[0241] A resist material comprising a polymer having a repeating unit represented by the following formula (b1) or (b2):

[0242] (In formula (b1) and formula (b2), R Ａ is a hydrogen atom or a methyl group. １ is a single bond or an ester group. ２ is a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms or an arylene group having 6 to 10 carbon atoms, and some of the methylene groups constituting the alkylene group may be substituted with an ether group, an ester group or a lactone ring-containing group; and X ２ At least one hydrogen atom contained in X is substituted with a bromine atom. ３ Rf is a single bond, an ether group, an ester group, or a linear, branched, or cyclic alkylene group having 1 to 12 carbon atoms, and some of the methylene groups constituting the alkylene group may be substituted with an ether group or an ester group. １ ~Rf ４ are each independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, but at least one is a fluorine atom or a trifluoromethyl group. １ and Rf ２ may combine to form a carbonyl group. １ ~R ５ are each independently a linear, branched, or cyclic alkyl group having 1 to 12 carbon atoms, a linear, branched, or cyclic alkenyl group having 2 to 12 carbon atoms, an alkynyl group having 2 to 12 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or an aryloxyalkyl group having 7 to 12 carbon atoms, in which some or all of the hydrogen atoms may be substituted with a hydroxy group, a carboxy group, a halogen atom, an oxo group, a cyano group, an amide group, a nitro group, a sultone group, a sulfone group, or a sulfonium salt-containing group, and in which some of the methylene groups constituting these groups may be substituted with an ether group, an ester group, a carbonyl group, a carbonate group, or a sulfonate ester group. １ and R ２may be bonded to form a ring together with the sulfur atom to which they are attached.

[0243] A resist material comprising a base resin containing a polymer containing a repeating unit represented by the following formula (a):

[0244] (In formula (a), R Ａ is a hydrogen atom or a methyl group. １ is a hydrogen atom or an acid labile group. ２ is a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, or a halogen atom other than bromine. １ X is a single bond, a phenylene group, or a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms which may contain an ester group or a lactone ring. ２ is -O-, -O-CH ２ - or -NH-. m is an integer of 1 to 4. u is an integer of 0 to 3. However, m+u is an integer of 1 to 4.

[0245] A resist composition that generates an acid upon exposure, and whose solubility in a developer changes due to the action of the acid, comprising: a base component (A) whose solubility in a developer changes due to the action of the acid; and a fluorine additive component (F) that exhibits decomposition in an alkaline developer, wherein the fluorine additive component (F) comprises a fluororesin component (F1) that has a structural unit (f1) that includes a base dissociable group, and a structural unit (f2) that includes a group represented by the following general formula (f2-r-1):

[0246] [In formula (f2-r-1), Rf ２１ are each independently a hydrogen atom, an alkyl group, an alkoxy group, a hydroxy group, a hydroxyalkyl group, or a cyano group. n" is an integer of 0 to 2. * is a bond.

[0247] The structural unit (f1) includes a structural unit represented by the following general formula (f1-1) or a structural unit represented by the following general formula (f1-2).

[0248] [In formulas (f1-1) and (f1-2), each R is independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. X is a divalent linking group that does not have an acid-dissociable site. A ａｒｙｌ represents a divalent aromatic cyclic group which may have a substituent. ０１ is a single bond or a divalent linking group. ２ are each independently an organic group having a fluorine atom.

[0249] Coatings, coating solutions, and coating compositions include, for example:

[0250] A coating comprising a metal oxo-hydroxo network with organic ligands via metal carbon bonds and / or metal carboxylate bonds.

[0251] Inorganic oxo-hydroxo-based compositions.

[0252] a coating solution comprising an organic solvent; a first organometallic composition having the formula R ｚ SnO （２－（ｚ／２）－（ｘ／２）） (OH) ｘ (where 0<z≦2 and 0<(z+x)≦4), formula R′ ｎ SnX ４－ｎ wherein n=1 or 2, or mixtures thereof, where R and R′ are independently hydrocarbyl groups having 1 to 31 carbon atoms, and X is a ligand having a hydrolyzable bond to Sn, or a combination thereof; and a hydrolyzable metal compound having the formula MX′ ｖ wherein M is a metal selected from Groups 2 to 16 of the Periodic Table of the Elements, v is a number from 2 to 6, and X' is a ligand having a hydrolyzable M-X bond or a combination thereof.

[0253] an organic solvent and a solution of the formula RSnO （３／２－ｘ／２） (OH) ｘand a first organometallic compound of the formula: wherein 0<x<3, wherein the solution contains from about 0.0025M to about 1.5M tin, and R is an alkyl or cycloalkyl group having from 3 to 31 carbon atoms, the alkyl or cycloalkyl group being bonded to the tin at a secondary or tertiary carbon atom.

[0254] An aqueous inorganic patterning precursor solution comprising a mixture of water, metal suboxide cations, polyatomic inorganic anions, and radiation-sensitive ligands comprising peroxide groups.

[0255] Irradiation with light or electron beams is carried out, for example, through a mask (reticle) for forming a predetermined pattern. For example, i-line, KrF excimer laser, ArF excimer laser, EUV (extreme ultraviolet), or EB (electron beam) can be used. The composition for forming a resist underlayer film of the present invention is preferably applied for EB (electron beam) or EUV (extreme ultraviolet: 13.5 nm) irradiation, more preferably for EUV (extreme ultraviolet) exposure. The irradiation energy of the electron beam and the exposure dose of light are not particularly limited.

[0256] After irradiation with light or electron beams and before development, baking (PEB: Post Exposure Bake) may be performed. The baking temperature is not particularly limited, but is preferably 60° C. to 150° C., more preferably 70° C. to 120° C., and particularly preferably 75° C. to 110° C. The baking time is not particularly limited, but is preferably 1 second to 10 minutes, more preferably 10 seconds to 5 minutes, and particularly preferably 30 seconds to 3 minutes.

[0257] For example, an alkaline developer is used for development. The development temperature can be, for example, 5°C to 50°C. The development time can be, for example, 10 seconds to 300 seconds. Examples of alkaline developers that can be used include aqueous solutions of alkalis such as inorganic alkalis (e.g., sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia); primary amines (e.g., ethylamine and n-propylamine); secondary amines (e.g., diethylamine and di-n-butylamine); tertiary amines (e.g., triethylamine and methyldiethylamine); alcohol amines (e.g., dimethylethanolamine and triethanolamine); quaternary ammonium salts (e.g., tetramethylammonium hydroxide, tetraethylammonium hydroxide, and choline); and cyclic amines (e.g., pyrrole and piperidine). Furthermore, the aqueous solutions of the alkalis can be used by adding an appropriate amount of alcohols (e.g., isopropyl alcohol) or a nonionic surfactant. Among these, preferred developers are aqueous solutions of quaternary ammonium salts, more preferably aqueous solutions of tetramethylammonium hydroxide and choline. Furthermore, surfactants and the like can also be added to these developers. Alternatively, development may be carried out with an organic solvent such as butyl acetate instead of an alkaline developer, and the portions of the photoresist where the alkaline dissolution rate is not improved may be developed.

[0258] Next, the resist underlayer film is etched using the formed resist pattern as a mask. The etching may be dry etching or wet etching, but dry etching is preferred. If the inorganic film is formed on the surface of the semiconductor substrate used, the surface of the inorganic film is exposed. If the inorganic film is not formed on the surface of the semiconductor substrate used, the surface of the semiconductor substrate is exposed. Thereafter, the semiconductor substrate is processed by a known method (e.g., dry etching), thereby manufacturing a semiconductor device.

[0259] Next, the present invention will be explained in detail with reference to synthesis examples and examples, but the present invention is not limited to these.

[0260] The weight-average molecular weights of the polymers shown in Synthesis Examples 1 to 5 below were measured by gel permeation chromatography (hereinafter abbreviated as GPC). A GPC device manufactured by Tosoh Corporation was used for the measurements, and the measurement conditions were as follows: Column temperature: 40°C, Flow rate: 0.35 ml / min, Eluent: tetrahydrofuran (THF), Standard sample: polystyrene (Tosoh Corporation).

[0261] Synthesis Example 1 Into a reaction flask was added 3.00 g of monoallyl diglycidyl isocyanuric acid (product name: MA-DGIC, manufactured by Shikoku Chemical Industry Co., Ltd.), 0.88 g of 1,2,3,4-cyclobutanetetracarboxylic dianhydride (manufactured by Tokyo Chemical Industry Co., Ltd.), 1.14 g of monoallyl isocyanuric acid (product name: MA-ICA, manufactured by Shikoku Chemical Industry Co., Ltd.), 0.19 g of tetrabutylphosphonium bromide (manufactured by Hokko Chemical Industry Co., Ltd.), and 0.05 g of 4-dimethylaminopyridine (manufactured by Tokyo Chemical Industry Co., Ltd.), and 21.07 g of propylene glycol monomethyl ether. The resulting mixture was heated and stirred in a nitrogen atmosphere at 120°C for 23 hours in a reaction flask. The resulting reaction product corresponded to formula (x-1), and had a weight average molecular weight Mw of 11,719 as measured by GPC in terms of polystyrene. (In formula (x-1), Me represents a methyl group, and m and n represent the average number of repetitions.)

[0262] Synthesis Example 2 A polymer having the same composition as the reaction product synthesized in Synthesis Example 3 of WO2018 / 203540 was synthesized. The synthesis method is described below. 29.21 g of propylene glycol monomethyl ether was added to 2.29 g of monoallyl diglycidyl isocyanuric acid (product name: MA-DGIC, manufactured by Shikoku Chemical Industry Co., Ltd.), 1.50 g of HP-4032D (manufactured by DIC Corporation), 3.15 g of 3,3'-dithiodipropionic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.34 g of tetrabutylphosphonium bromide (manufactured by Hokko Chemical Industry Co., Ltd.) in a reaction flask. The resulting mixture was heated and stirred in a nitrogen atmosphere at 105°C for 20 hours in a reaction flask. The resulting reaction product corresponded to formula (x-2), and had a weight average molecular weight Mw of 4,500 as measured by GPC in terms of polystyrene.

[0263] Example 1 43.039 g of propylene glycol monomethyl ether, 4.950 g of propylene glycol monomethyl ether acetate, 0.096 g of tetramethoxymethyl glycoluril (Nihon Cytec Industries Co., Ltd., product name: POWDERLINK [registered trademark] 1174), 0.009 g of phenolsulfonic acid (Tokyo Chemical Industry Co., Ltd.), and 0.004 g of a surfactant (NOF Corporation, product name: AP-001) were added to 1.900 g of a solution containing 0.385 g of the reaction product obtained by the method described in Synthesis Example 1 of JP 2016-128925 A to obtain a solution. The solution was then filtered using a polyethylene microfilter having a pore size of 0.02 μm to prepare a composition for forming a resist underlayer film. The surfactant was a copolymer of formula (IV) in which a was 0.35, b was 0.15, c was 0.50, d was 0.001, and n was 2-20. (In formula (IV), a, b, c, and d are each independently a number of 0 to 1 representing a mass ratio, and n is a number of 2 to 20 representing the average number of moles added.)

[0264] Example 2 42.791 g of propylene glycol monomethyl ether, 4.950 g of propylene glycol monomethyl ether acetate, 0.096 g of tetramethoxymethyl glycoluril (Nihon Cytec Industries Co., Ltd., trade name: POWDERLINK [registered trademark] 1174), 0.009 g of phenolsulfonic acid (Tokyo Chemical Industry Co., Ltd.), and 0.004 g of a surfactant (NOF Corporation, trade name: AP-001) were added to 2.148 g of a solution containing 0.385 g of the reaction product obtained by the method described in Synthesis Example 1 of WO 2005 / 098542 to form a solution. The solution was then filtered using a polyethylene microfilter having a pore size of 0.02 μm to prepare a composition for forming a resist underlayer film.

[0265] Example 3 42.792 g of propylene glycol monomethyl ether, 4.950 g of propylene glycol monomethyl ether acetate, 0.096 g of tetramethoxymethyl glycoluril (Nihon Cytec Industries Co., Ltd., trade name: POWDERLINK [registered trademark] 1174), 0.009 g of phenolsulfonic acid (Tokyo Chemical Industry Co., Ltd.), and 0.008 g of a surfactant (NOF Corporation, trade name: AP-001) were added to 2.147 g of a solution containing 0.385 g of the reaction product obtained by the method described in Synthesis Example 1 of WO 2009 / 096340 to form a solution. The solution was then filtered using a polyethylene microfilter having a pore size of 0.02 μm to prepare a composition for forming a resist underlayer film.

[0266] Example 4 43.105 g of propylene glycol monomethyl ether, 4.950 g of propylene glycol monomethyl ether acetate, 0.096 g of tetramethoxymethyl glycoluril (Nihon Cytec Industries Co., Ltd., trade name: POWDERLINK [registered trademark] 1174), 0.009 g of phenolsulfonic acid (Tokyo Chemical Industry Co., Ltd.), and 0.004 g of a surfactant (NOF Corporation, trade name: AP-001) were added to 1.834 g of a solution containing 0.385 g of a reaction product corresponding to the formula (x-1) to obtain a solution. The solution was then filtered using a polyethylene microfilter having a pore size of 0.02 μm to prepare a composition for forming a resist underlayer film.

[0267] Example 5 43.578 g of propylene glycol monomethyl ether, 4.950 g of propylene glycol monomethyl ether acetate, 0.095 g of tetramethoxymethyl glycoluril (Nihon Cytec Industries Co., Ltd., trade name: POWDERLINK [registered trademark] 1174), 0.009 g of phenolsulfonic acid (Tokyo Chemical Industry Co., Ltd.), and 0.011 g of a surfactant (NOF Corporation, trade name: AP-001) were added to 1.355 g of a solution containing 0.379 g of the reaction product obtained by the method described in Synthesis Example 2 of WO2017 / 191767 to form a solution. The solution was then filtered using a polyethylene microfilter having a pore size of 0.02 μm to prepare a composition for forming a resist underlayer film.

[0268] Example 6 42.583 g of propylene glycol monomethyl ether, 4.950 g of propylene glycol monomethyl ether acetate, 0.096 g of tetramethoxymethyl glycoluril (Nihon Cytec Industries Co., Ltd., trade name: POWDERLINK [registered trademark] 1174), 0.009 g of phenolsulfonic acid (Tokyo Chemical Industry Co., Ltd.), and 0.007 g of a surfactant (NOF Corporation, trade name: AP-001) were added to 2.329 g of a solution containing 0.378 g of a reaction product corresponding to the formula (x-2) to obtain a solution. The solution was then filtered using a polyethylene microfilter having a pore size of 0.02 μm to prepare a composition for forming a resist underlayer film.

[0269] Example 7 42.988 g of propylene glycol monomethyl ether, 4.950 g of propylene glycol monomethyl ether acetate, 0.096 g of tetramethoxymethyl glycoluril (Nihon Cytec Industries Co., Ltd., trade name: POWDERLINK [registered trademark] 1174), 0.009 g of phenolsulfonic acid (Tokyo Chemical Industry Co., Ltd.), and 0.004 g of a surfactant (NOF Corporation, trade name: AP-001) were added to 1.951 g of a solution containing 0.385 g of the reaction product obtained by the method described in Synthesis Example 1 of WO2003 / 017002 to form a solution. The solution was then filtered using a polyethylene microfilter having a pore size of 0.02 μm to prepare a composition for forming a resist underlayer film.

[0270] Comparative Example 1 43.027 g of propylene glycol monomethyl ether, 4.950 g of propylene glycol monomethyl ether acetate, 0.096 g of tetramethoxymethyl glycoluril (Nihon Cytec Industries Co., Ltd., product name: POWDERLINK (registered trademark) 1174), and 0.009 g of phenolsulfonic acid (Tokyo Chemical Industry Co., Ltd.) were added to 1.915 g of a solution containing 0.388 g of the reaction product obtained by the method described in Synthesis Example 1 of JP 2016-128925 A to obtain a solution. The solution was then filtered using a polyethylene microfilter having a pore size of 0.02 μm, to prepare a composition for forming a resist underlayer film.

[0271] Comparative Example 2 42.777 g of propylene glycol monomethyl ether, 4.950 g of propylene glycol monomethyl ether acetate, 0.096 g of tetramethoxymethyl glycoluril (Nihon Cytec Industries Co., Ltd., trade name: POWDERLINK (registered trademark) 1174), and 0.009 g of phenolsulfonic acid (Tokyo Chemical Industry Co., Ltd.) were added to 2.165 g of a solution containing 0.388 g of the reaction product obtained by the method described in Synthesis Example 1 of WO 2005 / 098542 to obtain a solution. The solution was then filtered using a polyethylene microfilter having a pore size of 0.02 μm to prepare a composition for forming a resist underlayer film.

[0272] Comparative Example 3 42.778 g of propylene glycol monomethyl ether, 4.950 g of propylene glycol monomethyl ether acetate, 0.096 g of tetramethoxymethyl glycoluril (Nihon Cytec Industries Co., Ltd., trade name: POWDERLINK (registered trademark) 1174), and 0.009 g of phenolsulfonic acid (Tokyo Chemical Industry Co., Ltd.) were added to 2.164 g of a solution containing 0.388 g of the reaction product obtained by the method described in Synthesis Example 1 of WO2009 / 096340 to obtain a solution. The solution was then filtered using a polyethylene microfilter having a pore size of 0.02 μm to prepare a composition for forming a resist underlayer film.

[0273] Comparative Example 4 To 1.848 g of a solution containing 0.388 g of a reaction product corresponding to the formula (x-1), 43.094 g of propylene glycol monomethyl ether, 4.950 g of propylene glycol monomethyl ether acetate, 0.096 g of tetramethoxymethyl glycoluril (Nihon Cytec Industries Co., Ltd., product name: POWDERLINK (registered trademark) 1174), and 0.009 g of phenolsulfonic acid (Tokyo Chemical Industry Co., Ltd.) were added to obtain a solution. The solution was then filtered using a polyethylene microfilter having a pore size of 0.02 μm, to prepare a composition for forming a resist underlayer film.

[0274] Comparative Example 5 43.555 g of propylene glycol monomethyl ether, 4.950 g of propylene glycol monomethyl ether acetate, 0.096 g of tetramethoxymethyl glycoluril (Nihon Cytec Industries Co., Ltd., product name: POWDERLINK (registered trademark) 1174), and 0.009 g of phenolsulfonic acid (Tokyo Chemical Industry Co., Ltd.) were added to 1.387 g of a solution containing 0.388 g of the reaction product obtained by the method described in Synthesis Example 2 of WO2017 / 191767 to obtain a solution. The solution was then filtered using a polyethylene microfilter having a pore size of 0.02 μm to prepare a composition for forming a resist underlayer film.

[0275] Comparative Example 6 42.552 g of propylene glycol monomethyl ether, 4.950 g of propylene glycol monomethyl ether acetate, 0.097 g of tetramethoxymethyl glycoluril (Nihon Cytec Industries Co., Ltd., product name: POWDERLINK (registered trademark) 1174), and 0.009 g of phenolsulfonic acid (Tokyo Chemical Industry Co., Ltd.) were added to 2.390 g of a solution containing 0.388 g of a reaction product corresponding to the above formula (x-2) to obtain a solution. The solution was then filtered using a polyethylene microfilter having a pore size of 0.02 μm to prepare a composition for forming a resist underlayer film.

[0276] Comparative Example 7 42.976 g of propylene glycol monomethyl ether, 4.950 g of propylene glycol monomethyl ether acetate, 0.097 g of tetramethoxymethyl glycoluril (Nihon Cytec Industries Co., Ltd., trade name: POWDERLINK (registered trademark) 1174), and 0.009 g of phenolsulfonic acid (Tokyo Chemical Industry Co., Ltd.) were added to 1.966 g of a solution containing 0.388 g of the reaction product obtained by the method described in Synthesis Example 1 of WO 2003 / 017002 to obtain a solution. The solution was then filtered using a polyethylene microfilter having a pore size of 0.02 μm to prepare a composition for forming a resist underlayer film.

[0277] [EBR Performance Evaluation] Each of the resist underlayer film-forming compositions prepared in Examples 1 to 7 and Comparative Examples 1 to 7 was spin-coated onto a silicon wafer with a diameter of 200 mm using a spin coater (CLEAN TRACK ACT8) manufactured by Tokyo Electron Limited, and EBR was performed using OK73 thinner (Tokyo Ohka Kogyo Co., Ltd.). The silicon wafer after coating was heated on a hot plate at 205°C for 1 minute to form a resist underlayer film with a thickness of 25 nm. The shape of the wafer edge (EBR shape evaluation) was then evaluated using an electron microscope (100x magnification) based on the following evaluation criteria. The results are shown in Table 1. Evaluation criteria "A" can be said to indicate a good EBR shape, and excellent removability by EBR. (Evaluation Criteria) A: The EBR line uniformity on the resist underlayer film is consistent. B: The EBR line uniformity on the resist underlayer film is not consistent.

[0278]

[0279] The results in Table 1 above demonstrate that the coating films prepared using the compositions for forming resist underlayer films prepared in Examples 1 to 7 can obtain good EBR profiles. Furthermore, it can be said that they exhibit good EBR profiles compared to Comparative Examples 1 to 7. Therefore, Examples 1 to 7 exhibit good removability by EBR compared to Comparative Examples 1 to 7, and are therefore useful as compositions for forming resist underlayer films.

[0280] [Evaluation of Hump Performance] The height of the hump at the edge shape portion of the resist underlayer film formed in the same manner as in the EBR performance evaluation was measured using a film thickness step gauge (Dektak XT) manufactured by Bruker Japan, and the hump height ratio to the film thickness (hump height ratio) was calculated using the following formula: Hump height ratio = Hump height [nm] ÷ Film thickness [nm] The results are shown in Table 2. The lower the hump height ratio, the better the removability in EBR.

[0281]

[0282] From the results in Table 2 above, it can be said that the coating films prepared using the compositions for forming a resist underlayer film prepared in Examples 1 to 7 exhibit better hump height ratios than those of Comparative Examples 1 to 7. Therefore, Examples 1 to 7 exhibit better hump height ratios than those of Comparative Examples 1 to 7, and therefore have excellent removability by EBR and are useful as compositions for forming a resist underlayer film.

[0283] Synthesis Example 3 Under nitrogen, 2,2'-biphenol (25.00 g, 0.1343 mol, manufactured by Tokyo Chemical Industry Co., Ltd.), 1-naphthaldehyde (10.484 g, 0.0671 mol, manufactured by Aldrich Chemical), 1-pyrenecarboxaldehyde (15.457 g, 0.0671 mol, manufactured by Tokyo Chemical Industry Co., Ltd.), and methanesulfonic acid (3.871 g, 0.0403 mol, manufactured by Tokyo Chemical Industry Co., Ltd.) were added to a 100 mL four-neck flask, and propylene glycol monomethyl ether (54.81 g, manufactured by Kanto Chemical Co., Ltd.) was further charged. The mixture was stirred and heated to 120°C to dissolve the mixture and initiate polymerization. After 24 hours, the mixture was allowed to cool to room temperature and reprecipitated in methanol (2500 g, manufactured by Kanto Chemical Co., Ltd.). The resulting precipitate was filtered and dried in a vacuum dryer at 50°C for 10 hours to obtain a reaction product. The resulting reaction product corresponds to formula (x-3), and had a weight average molecular weight Mw of 5,000 and a polydispersity index Mw / Mn of 2.12, as measured by GPC in terms of polystyrene.

[0284] Synthesis Example 4 Under nitrogen, a 100 mL four-neck flask was charged with N-phenyl-1-naphthylamine (10.00 g, 0.046 mol, manufactured by Tokyo Chemical Industry Co., Ltd.), 1-naphthaldehyde (7.12 g, 0.046 mol, manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.876 g of methanesulfonic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), and 25.37 g of propylene glycol monomethyl ether acetate was then added. The mixture was then heated to 120°C and allowed to cool to room temperature after approximately 12 hours, precipitated with methanol, and the resulting precipitate was dried to obtain a reaction product. The resulting reaction product corresponded to formula (x-4), and had a weight-average molecular weight Mw of 1,600 as measured by GPC in terms of polystyrene. To the resulting reaction product, cation exchange resin and anion exchange resin in amounts equal to the solid content were added, and the mixture was stirred for 4 hours. The ion exchange resin was filtered to obtain a polymer solution.

[0285] Synthesis Example 5 Under nitrogen, a 500 mL four-neck flask was charged with α,α'-dihydroxy-1,3-diisopropylbenzene (37.33 g, 0.1921 mol, manufactured by Tokyo Chemical Industry Co., Ltd.), N,N'-diphenyl-1,4-phenylenediamine (50.00 g, 0.1921 mol, manufactured by Tokyo Chemical Industry Co., Ltd.), and paratoluenesulfonic acid monohydrate (1.53 g, 0.008 mol, manufactured by Tokyo Chemical Industry Co., Ltd.), and 207.33 g of propylene glycol monomethyl ether acetate (PGMEA, manufactured by Kanto Chemical Co., Ltd.) was further charged, stirred, and heated until reflux was confirmed to dissolve the mixture and initiate polymerization. After 16 hours, the mixture was allowed to cool to 60°C and then reprecipitated in methanol (1600 g, manufactured by Kanto Chemical Co., Ltd.). The resulting precipitate was filtered and dried in a vacuum dryer at 50°C for 16 hours to obtain the target reaction product (56.04 g) having a structural unit represented by formula (x-5). The weight average molecular weight Mw of the resulting reaction product measured by GPC in terms of polystyrene was 2,700.

[0286] Example 8 13.981 g of propylene glycol monomethyl ether, 24.779 g of propylene glycol monomethyl ether acetate, and 0.034 g of a surfactant (NOF Corporation, trade name: AP-001) were added to 11.206 g of a solution containing 3.362 g of the reaction product obtained by the method described in Synthesis Example 3 to obtain a solution. The solution was then filtered using a polyethylene microfilter having a pore size of 0.02 μm to prepare a composition for forming a resist underlayer film.

[0287] Example 9 To 8.1391 g of a solution containing 2.692 g of the reaction product obtained by the method described in Synthesis Example 4, 18.654 g of propylene glycol monomethyl ether, 13.207 g of propylene glycol monomethyl ether acetate, 0.539 g of 3,3',5,5'-tetrakis(methoxymethyl)biphenyl-4,4'-diol, 0.080 g of pyridinium-para-phenolsulfonic acid, and 0.054 g of a surfactant (NOF Corporation, trade name: AP-001) were added to obtain a solution. The resulting solution was then filtered using a polyethylene microfilter having a pore size of 0.02 μm to prepare a composition for forming a resist underlayer film.

[0288] Example 10 9.327 g of propylene glycol monomethyl ether, 21.618 g of propylene glycol monomethyl ether acetate, 0.543 g of 3,3',5,5'-tetrakis(methoxymethyl)biphenyl-4,4'-diol, 0.081 g of pyridinium-para-phenolsulfonic acid, and 0.027 g of a surfactant (NOF Corporation, trade name: AP-001) were added to 9.077 g of a solution containing 2.714 g of the reaction product obtained by the method described in Synthesis Example 5 to form a solution. The solution was then filtered using a polyethylene microfilter having a pore size of 0.02 μm to prepare a composition for forming a resist underlayer film.

[0289] Comparative Example 8 A composition for forming a resist underlayer film was prepared in the same manner as in Example 8, except that the surfactant (NOF Corporation, trade name: AP-001) was not added.

[0290] Comparative Example 9 A composition for forming a resist underlayer film was prepared in the same manner as in Example 9, except that the surfactant (NOF Corporation, trade name: AP-001) was not added.

[0291] Comparative Example 10 A composition for forming a resist underlayer film was prepared in the same manner as in Example 10, except that the surfactant (NOF Corporation, trade name: AP-001) was not added.

[0292] [EBR Performance Evaluation] Each of the resist underlayer film-forming compositions prepared in Examples 8 to 10 and Comparative Examples 8 to 10 was spin-coated onto a silicon wafer with a diameter of 300 mm using a spin coater (CLEAN TRACK LITHIUS Pro) manufactured by Tokyo Electron Limited, and EBR was performed using OK73 thinner (Tokyo Ohka Kogyo Co., Ltd.). After coating, the silicon wafer was heated on a hot plate at 240°C to 400°C for 60 to 90 seconds to form a resist underlayer film with a film thickness of 145 to 190 nm. The shape of the wafer edge (EBR shape evaluation) was then evaluated using an electron microscope (100x magnification) based on the following evaluation criteria. The results are shown in Table 3. Evaluation criteria "A" can be said to indicate a good EBR shape and excellent removability by EBR. (Evaluation Criteria) A: EBR line uniformity on the resist underlayer film is constant B: EBR line uniformity on the resist underlayer film is not constant

[0293]

[0294] The results in Table 3 above demonstrate that the coating films prepared using the compositions for forming resist underlayer films prepared in Examples 8 to 10 can obtain good EBR profiles. Furthermore, it can be said that they exhibit good EBR profiles compared to Comparative Examples 8 to 10. Therefore, Examples 8 to 10 exhibit good removability by EBR compared to Comparative Examples 8 to 10, and are therefore useful as compositions for forming resist underlayer films.

[0295] [Evaluation of Hump Performance] The height of the hump at the edge shape portion of the resist underlayer film formed in the same manner as in the EBR performance evaluation was measured using a film thickness step gauge (Dektak XT) manufactured by Bruker Japan, and the hump height ratio to the film thickness (hump height ratio) was calculated using the following formula: Hump height ratio = Hump height [nm] ÷ Film thickness [nm] The results are shown in Table 4. The lower the hump height ratio, the better the removability by EBR.

[0296]

[0297] From the results in Table 4 above, it can be said that the coating films prepared using the compositions for forming a resist underlayer film prepared in Examples 8 to 10 had hump height ratios that were 50% or more lower than those of Comparative Examples 8 to 10, and thus showed good results in improving humps. Therefore, Examples 8 to 10 showed good hump height ratios compared to Comparative Examples 8 to 10, and therefore had excellent removability by EBR, and were useful as compositions for forming a resist underlayer film.

Claims

1. A composition for forming a resist underlayer film, comprising a resin (A), a solvent (B) and a surfactant (C), wherein the surfactant (C) is a copolymer containing structural units derived from monomers represented by the following formulas (I), (II) and (III): (In formula (I), R １ represents a hydrogen atom or a methyl group, R ２ represents an alkylene group having 1 to 4 carbon atoms; R ３ represents an aliphatic hydrocarbon group having 10 to 30 carbon atoms. ４ and R ５ may be the same or different and each represents a hydrogen atom or a methyl group, AO represents an oxyalkylene group having 2 to 4 carbon atoms, and n represents the average number of moles added, which is 1 to 200. In formula (III), R ６ is an aliphatic hydrocarbon group having 1 to 12 carbon atoms.

2. The composition for forming a resist underlayer film according to claim 1, wherein the surfactant (C) is a copolymer containing structural units derived from two or more types of monomers represented by formula (I).

3. The composition for forming a resist underlayer film according to claim 1, wherein the resin (A) comprises at least one selected from the group consisting of polyester resins, acrylic resins, methacrylic resins, resins containing an aromatic ring, polyether resins, arylene resins, triazine resins and calixarene resins.

4. The composition for forming a resist underlayer film according to claim 1, wherein the resin (A) has a repeating unit represented by the following formula (1): (In the formula, A is, independently of each other, a hydrogen atom, a methyl group, or an ethyl group; Q １ and Q. ２ represents the following formula (2) or the following formula (3): (In formula (2), Q ３ represents an alkylene group having 1 to 10 carbon atoms, which may contain a sulfide bond or a disulfide bond, an alkenylene group having 2 to 10 carbon atoms, a phenylene group, a naphthylene group, or an anthrylene group. The phenylene group, naphthylene group, and an anthrylene group may each independently be substituted with a group selected from the group consisting of an alkyl group having 1 to 6 carbon atoms, a phenyl group, a halogen atom, an alkoxy group having 1 to 6 carbon atoms, a nitro group, a cyano group, a hydroxyl group, and an alkylthio group having 1 to 6 carbon atoms. In formula (3), B each independently represents a single bond or an alkylene group having 1 to 5 carbon atoms. In formulas (2) and (3), * represents a bond. Each n is independently 0 or 1. Each m is independently 0 or 1. Each X is a group represented by the following formula (4), (5), or (6). (In formula (4) and formula (5), R １ each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 3 to 6 carbon atoms, a benzyl group, or a phenyl group. The alkyl group and the alkenyl group may be substituted with a halogen atom, a hydroxy group, or a cyano group. The benzyl group may have a hydrogen atom on the aromatic ring substituted with a hydroxy group. The phenyl group may be substituted with a group selected from the group consisting of an alkyl group having 1 to 6 carbon atoms, a halogen atom, an alkoxy group having 1 to 6 carbon atoms, a nitro group, a cyano group, a hydroxy group, and an alkylthio group having 1 to 6 carbon atoms, and two R １ may be bonded to each other to form a ring having 3 to 6 carbon atoms. ２ represents a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 3 to 6 carbon atoms, a benzyl group, or a phenyl group. The phenyl group may be substituted with a group selected from the group consisting of an alkyl group having 1 to 6 carbon atoms, a halogen atom, an alkoxy group having 1 to 6 carbon atoms, a nitro group, a cyano group, a hydroxy group, and an alkylthio group having 1 to 6 carbon atoms. １ and Q. ２ At least one of the above contains a structure represented by formula (3).

5. The composition for forming a resist underlayer film according to claim 1, wherein the resin (A) has a composite unit structure represented by the following formula (AB): (In formula (AB), A represents a unit structure (A) having an aromatic ring, and B represents a unit structure (B) having one or more carbon atoms.) 6. The composition for forming a resist underlayer film according to claim 1, wherein the solvent (B) comprises at least one selected from the group consisting of alkylene glycol monoalkyl ethers and monocarboxylic acid esters of alkylene glycol monoalkyl ethers.

7. The composition for forming a resist underlayer film according to claim 1, further comprising a crosslinking agent (D).

8. The composition for forming a resist underlayer film according to claim 7, wherein the crosslinking agent (D) is at least one selected from the group consisting of aminoplast crosslinking agents and phenoplast crosslinking agents.

9. The composition for forming a resist underlayer film according to claim 1, further comprising a curing catalyst (E).

10. A resist underlayer film which is a cured product of the composition for forming a resist underlayer film according to any one of claims 1 to 9.

11. A laminate comprising: a semiconductor substrate; and the resist underlayer film according to claim 10.

12. A method for manufacturing a semiconductor device, comprising: a step of forming a resist underlayer film on a semiconductor substrate using a composition for forming a resist underlayer film according to any one of claims 1 to 9; and a step of forming a resist film on the resist underlayer film.

13. A pattern formation method comprising the steps of: forming a resist underlayer film on a semiconductor substrate using a composition for forming a resist underlayer film according to any one of claims 1 to 9; forming a resist film on the resist underlayer film; irradiating the resist film with light or an electron beam and then developing the resist film to obtain a resist pattern; and etching the resist underlayer film using the resist pattern as a mask.

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