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

Abstract

Provided is a composition for forming a resist underlayer film, said composition containing: a metal compound; a polymer having a first structural unit represented by formula (1) and a second structural unit represented by formula (2); and a solvent. (In formula (1), R1 is a hydrogen atom or a substituted or unsubstituted C1-20 monovalent hydrocarbon group. R2 is a substituted or unsubstituted C1-20 monovalent hydrocarbon group.) (In formula (2), R3 is a hydrogen atom or a substituted or unsubstituted C1-20 monovalent hydrocarbon group. L is a single bond or a divalent linking group. Ar is a group obtained by removing (n+1) hydrogen atoms from a substituted or unsubstituted 6 to 20-membered aromatic ring. R4 is a C1-10 monovalent hydroxyalkyl group or hydroxy group. n is an integer from 0 to 8. When n is 2 or more, the plurality of R4 groups are the same or different.)

Description

[Technical Field]

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

[0002] In the manufacturing of semiconductor substrates and the like, a metal hard mask composition, which serves as a resist underlayer film, has been proposed (see Japanese Patent Publication No. 2013-185155). CleanTrack is generally used when manufacturing semiconductor substrates and the like. CleanTrack is a device that can perform processing steps such as spin coating, EBR (Edge Bead Removal), back rinsing, and firing in an integrated manner. The EBR process is a process in which, after forming a film on the substrate (wafer) by spin coating, the film on the edges (periphery) of the substrate is removed with a removal solution. This prevents contamination of the substrate transport arm of the CleanTrack. Contamination of the transport arm can cause defects and reduce the yield of device manufacturing. Removal solutions used in the EBR process include a mixture of propylene glycol monomethyl ether acetate and propylene glycol monoethyl ether (30:70, mass ratio), and are widely used in the EBR process of resist films and resist underlayer films (silicon-containing films, organic underlayer films, metal hard masks). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2013-185155 [Overview of the project] [Problems that the invention aims to solve]

[0004] Compositions for forming resist underlayer films (metal hard mask compositions) require not only uniform coating properties on the substrate surface, but also good wafer edge removal properties (smoothness of the boundary between the remaining and removed parts of the metal hard mask) and suppression of film thickness changes (humps) in the EBR process.

[0005] The present invention has been made based on the circumstances described above, and its objective is to provide a resist underlayer film formation composition that is excellent in terms of coating properties, wafer edge removal properties during the EBR process, and hump suppression properties, as well as a method for manufacturing a semiconductor substrate using the same, and a method for forming a resist underlayer film. [Means for solving the problem]

[0006] In one embodiment, the present invention is Metal compounds (hereinafter also referred to as "[A] compounds") and A polymer having a first structural unit represented by the following formula (1) (hereinafter also referred to as "structural unit (I)") and a second structural unit represented by the following formula (2) (hereinafter also referred to as "structural unit (II)") (hereinafter also referred to as "[B] polymer"), The solvent (hereinafter also referred to as "[C] solvent") and This invention relates to a composition for forming a resist underlayer film, which contains the following: [ka] (In formula (1), R 1 R is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, either substituted or unsubstituted. 2 (This refers to a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms.) [ka] (In formula (2), R 3 R is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, either substituted or unsubstituted. L is a single bond or a divalent linking group. Ar is a group obtained by removing (n+1) hydrogen atoms from an aromatic ring having 6 to 20 members, either substituted or unsubstituted. 4is a monovalent hydroxyalkyl group or hydroxy group having 1 to 10 carbon atoms. n is an integer of 0 to 8. When n is 2 or more, a plurality of R 4 are the same or different. )

[0007] In one embodiment, the present invention A step of coating a resist underlayer film forming composition directly or indirectly on a substrate; A step of forming a resist pattern directly or indirectly on the resist underlayer film formed by the coating step; A step of forming a pattern on the resist underlayer film by etching using the resist pattern as a mask including wherein the resist underlayer film forming composition a metal compound, a polymer having a first structural unit represented by the following formula (1) and a second structural unit represented by the following formula (2), a solvent and relates to a method for manufacturing a semiconductor substrate. [Chemical formula] (In formula (1), R 1 is a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms. R 2 is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms. ) [Chemical formula] (In formula (2), R 3 is a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms. L is a single bond or a divalent linking group. Ar is a group obtained by removing (n + 1) hydrogen atoms from a substituted or unsubstituted aromatic ring having 6 to 20 ring members. R 4 is a monovalent hydroxyalkyl group or hydroxy group having 1 to 10 carbon atoms. n is an integer of 0 to 8. When n is 2 or more, a plurality of R 4 are the same or different. )

[0008] Also, in another embodiment, the present invention A process of coating a resist underlayer film formation composition directly or indirectly onto a substrate. Equipped with, The above resist underlayer film forming composition, Metal compounds and, A polymer having a first structural unit represented by the following formula (1) and a second structural unit represented by the following formula (2) Solvent and, This relates to a method for forming a resist underlayer film containing [a specific component]. [ka] (In formula (1), R 1 R is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, either substituted or unsubstituted. 2 (This refers to a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms.) [ka] (In formula (2), R 3 R is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, either substituted or unsubstituted. L is a single bond or a divalent linking group. Ar is a group obtained by removing (n+1) hydrogen atoms from an aromatic ring having 6 to 20 members, either substituted or unsubstituted. 4 R is a monovalent hydroxyalkyl group or hydroxyl group having 1 to 10 carbon atoms. n is an integer from 0 to 8. If n is 2 or greater, multiple R 4 They are either the same or different. [Effects of the Invention]

[0009] The resist underlayer film formation composition is excellent in terms of coating properties, wafer edge removal properties during the EBR process, and hump suppression properties. The semiconductor substrate manufacturing method uses a resist underlayer film formation composition that is excellent in terms of coating properties, wafer edge removal properties during the EBR process, and hump suppression properties, thus enabling the efficient production of high-quality semiconductor substrates. The resist underlayer film formation method uses a resist underlayer film formation composition that is excellent in terms of coating properties, wafer edge removal properties during the EBR process, and hump suppression properties, thus enabling the efficient formation of a desired resist underlayer film. Therefore, these can be suitably used in the manufacture of semiconductor devices, where further miniaturization is expected in the future. [Brief explanation of the drawing]

[0010] [Figure 1A] This is an optical microscope image (10x magnification) showing a wafer edge removal performance evaluation where no unevenness in removal was observed. [Figure 1B] This is an optical microscope image (10x magnification) showing uneven removal during the evaluation of wafer edge removal performance. [Modes for carrying out the invention]

[0011] The following describes in detail the resist underlayer film formation compositions, semiconductor substrate manufacturing methods, and resist underlayer film formation methods according to each embodiment of the present invention. The resist underlayer film formation compositions will be described as appropriate within the description of the semiconductor substrate manufacturing method. Preferred combinations of embodiments are also preferred.

[0012] Method for manufacturing semiconductor substrates The method for manufacturing the semiconductor substrate includes a step of directly or indirectly coating the substrate with the resist underlayer film forming composition (hereinafter also referred to as the "composition") (hereinafter also referred to as the "coating step"), a step of directly or indirectly forming a resist pattern on the resist underlayer film formed by the coating step (hereinafter also referred to as the "resist pattern formation step"), and a step of forming a pattern on the resist underlayer film by etching using the resist pattern as a mask (hereinafter also referred to as the "etching step").

[0013] According to this semiconductor substrate manufacturing method, a resist underlayer film is formed using a resist underlayer film formation composition that is excellent in terms of coating properties, wafer edge removal properties during the EBR process, and hump suppression properties, thus enabling the efficient manufacture of high-quality semiconductor substrates.

[0014] The method for manufacturing the semiconductor substrate may further include, if necessary, a step of directly or indirectly forming an organic underlayer film on the substrate having the resist underlayer film formed by the coating step, prior to the resist pattern formation step (hereinafter also referred to as the "organic underlayer film formation step").

[0015] The method for manufacturing the semiconductor substrate may, if necessary, further include a step of directly or indirectly forming a silicon-containing film on the substrate having the resist underlayer film formed by the coating step, prior to the resist pattern formation step (hereinafter also referred to as the "silicon-containing film formation step").

[0016] The following describes the resist underlayer film formation composition used in the semiconductor substrate manufacturing method, as well as each step when the method includes the optional steps of organic underlayer film formation and silicon-containing film formation.

[0017] <Composition for forming a resist underlayer film> The resist underlayer film forming composition (hereinafter also simply referred to as "the composition") contains [A] a compound, [B] a polymer, and [C] a solvent. The composition may also contain other optional components as long as they do not impair the effects of the present invention.

[0018] [[A] compound] [A] A compound is a compound that contains a metal atom and an oxygen atom. [A] Examples of metal atoms that make up a compound include metal atoms from groups 3 to 16 of the periodic table (excluding silicon atoms). [A] A compound may have one or more metal atoms.

[0019] Examples of metal atoms in Group 3 include scandium, yttrium, lanthanum, and cerium. Examples of metal atoms in Group 4 include titanium, zirconium, and hafnium. Examples of metal atoms in Group 5 include vanadium, niobium, and tantalum. Examples of metal atoms in Group 6 include chromium, molybdenum, and tungsten. Examples of metal atoms in Group 7 include manganese and rhenium. Examples of metal atoms in Group 8 include iron, ruthenium, and osmium. Examples of metal atoms in Group 9 include cobalt, rhodium, and iridium. Examples of metal atoms in Group 10 include nickel, palladium, and platinum. Examples of metal atoms in Group 11 include copper, silver, and gold. Examples of metal atoms in Group 12 include zinc, cadmium, and mercury. Examples of metal atoms in Group 13 include aluminum, gallium, and indium. Examples of metal atoms in Group 14 include germanium, tin, and lead. Examples of metal atoms in Group 15 include antimony and bismuth. Examples of metal atoms in Group 16 include tellurium.

[0020] The metal atoms constituting the above [A] compound are preferably from groups 3 to 16, more preferably from groups 4 to 14, even more preferably from groups 4, 5, and 14, and particularly preferably from group 4. Specifically, titanium, zirconium, hafnium, tantalum, tungsten, tin, or combinations thereof are even more preferred.

[0021] The components other than the metal atoms that make up the above [A] compound (hereinafter also referred to as "[x] compound") include organic acids (hereinafter also referred to as "[a] organic acid"), hydroxy acid esters, β-diketones, β-ketoester Amine compounds are preferred. Here, "organic acid" refers to an organic compound that exhibits acidity, and "organic compound" refers to a compound having at least one carbon atom.

[0022] [a] Examples of organic acids include carboxylic acids, sulfonic acids, sulfinic acids, organic phosphinic acids, organic phosphonic acids, phenols, enols, thiols, acid imides, oximes, sulfonamides, and the like.

[0023] Examples of the carboxylic acids mentioned above include monocarboxylic acids such as formic acid, acetic acid, propionic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, 2-ethylhexanoic acid, oleic acid, acrylic acid, methacrylic acid, trans-2,3-dimethylacrylic acid, stearic acid, linoleic acid, linolenic acid, arachidonic acid, salicylic acid, benzoic acid, p-aminobenzoic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, trifluoroacetic acid, pentafluoropropionic acid, gallic acid, and shikimic acid; dicarboxylic acids such as oxalic acid, malonic acid, maleic acid, methylmalonic acid, fumaric acid, adipic acid, sebacic acid, phthalic acid, and tartaric acid; and carboxylic acids having three or more carboxyl groups, such as citric acid.

[0024] Examples of the above-mentioned sulfonic acids include benzenesulfonic acid and p-toluenesulfonic acid.

[0025] Examples of the above-mentioned sulfinic acid include benzenesulfinic acid and p-toluenesulfinic acid.

[0026] Examples of the above-mentioned organic phosphinic acids include diethylphosphinic acid, methylphenylphosphinic acid, and diphenylphosphinic acid.

[0027] Examples of the above-mentioned organic phosphonic acids include methylphosphonic acid, ethylphosphonic acid, t-butylphosphonic acid, cyclohexylphosphonic acid, and phenylphosphonic acid.

[0028] Examples of the above-mentioned phenols include monovalent phenols such as phenol, cresol, 2,6-xylenol, and naphthol; Divalent phenols such as catechol, resorcinol, hydroquinone, and 1,2-naphthalenediol; Examples include pyrogallol, 2,3,6-naphthalentriol, and other phenols with a valency of three or higher.

[0029] Examples of the above-mentioned enols include 2-hydroxy-3-methyl-2-butene and 3-hydroxy-4-methyl-3-hexene.

[0030] Examples of the thiols mentioned above include mercaptoethanol and mercaptopropanol.

[0031] Examples of the above-mentioned acid imides include carboxylic acid imides such as maleimide and succinimide, as well as sulfonamides such as di(trifluoromethanesulfonic acid)imide and di(pentafluoroethanesulfonic acid)imide.

[0032] Examples of the oximes mentioned above include aldoximes such as benzaldoxime and salicylaldoxime, as well as ketoximes such as diethylketoxime, methylethylketoxime, and cyclohexanone oxime.

[0033] Examples of the above-mentioned sulfonamides include methyl sulfonamide, ethyl sulfonamide, benzene sulfonamide, and toluene sulfonamide.

[0034] [a] As organic acids, carboxylic acids are preferred, monocarboxylic acids are more preferred, and methacrylic acid and benzoic acid are even more preferred.

[0035] Examples of the hydroxy acid esters mentioned above include glycolic acid esters, lactate esters, 2-hydroxycyclohexane-1-carboxylic acid esters, salicylic acid esters, and the like.

[0036] Examples of the above-mentioned β-diketones include 2,4-pentanedione, 3-methyl-2,4-pentanedione, and 3-ethyl-2,4-pentanedione.

[0037] Examples of the above-mentioned β-ketoesters include acetoacetic acid esters, α-alkyl-substituted acetoacetic acid esters, β-ketopentanoic acid esters, benzoyl acetate esters, and 1,3-acetonedicarboxylic acid esters.

[0038] Examples of amine compounds include diethanolamine and triethanolamine.

[0039] The above [A] compound is preferably a metal compound composed of a metal atom and an [a] organic acid, more preferably a metal compound composed of a metal atom from Group 4, Group 5, and Group 14 and a carboxylic acid, and even more preferably a metal compound composed of titanium, zirconium, hafnium, tantalum, tungsten, or tin and methacrylic acid or benzoic acid.

[0040] [A] Compound may contain one or more of the above-mentioned metal compounds.

[0041] [A] Compound may contain one or more [a] organic acids.

[0042] The lower limit of the content of compound [A] in the total components contained in the composition is preferably 2% by mass, more preferably 4% by mass, and still more preferably 6% by mass. The upper limit of the above content is preferably 30% by mass, more preferably 20% by mass, and still more preferably 15% by mass.

[0043] [[A] Method for synthesizing compounds] [A] Compounds can be synthesized, for example, by a hydrolysis condensation reaction using a [b] metal-containing compound, or by a ligand exchange reaction using a [b] metal-containing compound. Here, "hydrolysis condensation reaction" refers to a reaction in which the hydrolyzable group of the [b] metal-containing compound is hydrolyzed and converted to -OH, and the two resulting -OH groups undergo dehydration condensation to form -O-.

[0044] ([b] Metal-containing compounds) [b] The metal-containing compound is a metal compound (b1) having a hydrolyzable group, a hydrolyzate of a metal compound (b1) having a hydrolyzable group, a hydrolyzed condensate of a metal compound (b1) having a hydrolyzable group, or a combination thereof. The metal compound (b1) can be used alone or in combination of two or more types.

[0045] Examples of the hydrolyzable groups mentioned above include halogen atoms, alkoxy groups, and acyloxy groups.

[0046] Examples of the halogen atoms mentioned above include fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, and the like.

[0047] Examples of the alkoxy groups mentioned above include methoxy groups, ethoxy groups, n-propoxy groups, isopropoxy groups, and n-butoxy groups.

[0048] Examples of the above-mentioned acyloxy groups include acetoxy group, ethylyloxy group, propionyloxy group, butyryloxy group, t-butyryloxy group, t-amiryloxy group, n-hexanecarbonyloxy group, and n-octanecarbonyloxy group.

[0049] The hydrolyzable groups mentioned above are preferably alkoxy groups and acyloxy groups, and more preferably isopropoxy groups and acetoxy groups.

[0050] [b] When the metal-containing compound is a hydrolysis condensate of the metal compound (b1), the hydrolysis condensate of the metal compound (b1) may be a hydrolysis condensate of the metal compound (b1) having a hydrolyzable group and a compound containing a metalloid atom, as long as the effects of the present invention are not impaired. That is, the hydrolysis condensate of the metal compound (b1) may contain a metalloid atom to the extent that the effects of the present invention are not impaired. Examples of the metalloid atom include silicon, boron, germanium, antimony, tellurium, etc. The content of the metalloid atom in the hydrolysis condensate of the metal compound (b1) is usually less than 50 atomic percent of the total amount of metal atoms and metalloid atoms in the hydrolysis condensate. The upper limit of the content of the metalloid atom is preferably 30 atomic percent and more preferably 10 atomic percent of the total amount of metal atoms and metalloid atoms in the hydrolysis condensate.

[0051] Examples of metal compounds (b1) include the compound represented by the following formula (α) (hereinafter also referred to as "[m] compound").

[0052] [ka]

[0053] In the above formula (α), M is a metal atom. L is a ligand. a is an integer from 0 to 2. If a is 2, multiple Ls may be the same or different. Y is a hydrolyzable group selected from halogen atoms, alkoxy groups, and acyloxy groups. b is an integer from 2 to 6. Multiple Ys may be the same or different. Note that L is a ligand that does not correspond to Y.

[0054] Examples of metal atoms represented by M include those similar to those exemplified as metal atoms constituting the metal compounds contained in compound [A].

[0055] Ligands represented by L include monodentate ligands and polydentate ligands.

[0056] Examples of the monodentate ligands mentioned above include hydroxo ligands, carboxyl ligands, amide ligands, and ammonia.

[0057] Examples of the above-mentioned amide ligands include unsubstituted amide ligands (NH2), methylamide ligands (NHMe), dimethylamide ligands (NMe2), diethylamide ligands (NEt2), and dipropylamide ligands (NPr2).

[0058] Examples of the polydentate ligands mentioned above include hydroxy acid esters, β-diketones, β-ketoesters, β-dicarboxylic acid esters, hydrocarbons having π bonds, and diphosphines.

[0059] Examples of the hydroxy acid esters mentioned above include glycolic acid esters, lactate esters, 2-hydroxycyclohexane-1-carboxylic acid esters, salicylic acid esters, and the like.

[0060] Examples of the above-mentioned β-diketones include 2,4-pentanedione, 3-methyl-2,4-pentanedione, and 3-ethyl-2,4-pentanedione.

[0061] Examples of the above-mentioned β-ketoesters include acetoacetic acid esters, α-alkyl-substituted acetoacetic acid esters, β-ketopentanoic acid esters, benzoyl acetate esters, and 1,3-acetonedicarboxylic acid esters.

[0062] Examples of the above-mentioned β-dicarboxylic acid esters include malonic acid diesters, α-alkyl-substituted malonic acid diesters, α-cycloalkyl-substituted malonic acid diesters, and α-aryl-substituted malonic acid diesters.

[0063] Examples of hydrocarbons having the above-mentioned π bond include, Chain-like olefins such as ethylene and propylene; Cyclopentene, cyclohexene, norbornene, and other cyclic olefins; Chain-like dienes such as butadiene and isoprene; Cyclic dienes such as cyclopentadiene, methylcyclopentadiene, pentamethylcyclopentadiene, cyclohexadiene, norbornadiene; Examples include aromatic hydrocarbons such as benzene, toluene, xylene, hexamethylbenzene, naphthalene, and indene.

[0064] Examples of the above-mentioned diphosphines include 1,1-bis(diphenylphosphino)methane, 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl, and 1,1'-bis(diphenylphosphino)ferrocene.

[0065] Examples of halogen atoms represented by Y include fluorine, chlorine, bromine, and iodine atoms.

[0066] Examples of alkoxy groups represented by Y include methoxy, ethoxy, propoxy, and butoxy groups.

[0067] Examples of acyloxy groups represented by Y include acetoxy group, ethylyloxy group, butyryloxy group, t-butyryloxy group, t-amiryloxy group, n-hexanecarbonyloxy group, and n-octanecarbonyloxy group.

[0068] For Y, alkoxy groups and acyloxy groups are preferred, and isopropoxy groups and acetoxy groups are more preferred.

[0069] For b, 3 and 4 are preferred, with 4 being more preferred.

[0070] [b] Preferred metal-containing compounds are metal alkoxides that have not undergone hydrolysis or hydrolysis condensation, and metal acyloxides that have not undergone hydrolysis or hydrolysis condensation.

[0071] [b]Metal-containing compounds include zirconium tetra-n-butoxide, zirconium tetra-n-propoxide, zirconium tetraisopropoxide, hafnium tetraethoxide, indium triisopropoxide, hafnium tetraisopropoxide, hafnium tetra-n-propoxide, hafnium tetra-n-butoxide, tantalum pentaethoxide, tantalum pentane-butoxide, tungsten pentamethoxide, tungsten pentane-butoxide, tungsten hexaethoxide, tungsten hexane-butoxide, iron chloride, zinc diisopropoxide, zinc acetate dihydrate, ortho Tetrabutyl titanate, titanium tetra-n-butoxide, titanium tetra-n-propoxide, zirconium di-n-butoxide bis(2,4-pentane dionate), titanium tri-n-butoxide stearate, bis(cyclopentadienyl)hafnium dichloride, bis(cyclopentadienyl)tungsten dichloride, diacetato[(S)-(-)-2,2'-bis(diphenylphosphino)-1,1'-binaphthyl]ruthenium, dichloro[ethylenebis(diphenylphosphine)]cobalt, titanium butoxide oligomer, aminopropyltrimethoxytitanium, aminopropyltriethoxyzirconium, 2-(3,4-Epoxycyclohexyl)ethyltrimethoxyzirconium, γ-glycidoxypropyltrimethoxyzirconium, 3-isocyanopropyltrimethoxyzirconium, 3-isocyanopropyltriethoxyzirconium, triethoxymono(acetylacetonate)titanium, tri-n-propoxymono(acetylacetonate)titanium, tri-isopropoxymono(acetylacetonate)titanium, triethoxymono(acetylacetonate)zirconium, tri-n-propoxymono(acetylacetonate) Examples include (3-) zirconium, tri-isopropoxymono(acetylacetonate) zirconium, diisopropoxybis(acetylacetonate) titanium, di-n-butoxybis(acetylacetonate) titanium, di-n-butoxybis(acetylacetonate) zirconium, tri(3-methacryloxypropyl) methoxyzirconium, tri(3-acryloxypropyl) methoxyzirconium, tin tetraisopropoxide, tin tetra-n-butoxide, lanthanum oxide, yttrium oxide, etc.

[0072] Among these, metal alkoxides and metal acyloxides are preferred, metal alkoxides are more preferred, and titanium, zirconium, hafnium, tantalum, tungsten, and tin alkoxides are even more preferred.

[0073] [A] When using an organic acid in the synthesis of the compound, the lower limit of the amount of organic acid used is preferably 1 mole and more preferably 2 moles per mole of the metal-containing compound. On the other hand, the upper limit of the amount of organic acid used is preferably 6 moles and more preferably 5 moles per mole of the metal-containing compound.

[0074] [A] In the synthesis reaction of the compound, in addition to the metal compound (b1) and the organic acid [a], compounds that can act as a polydentate ligand represented by L in the compound of formula (α) above, or compounds that can act as a bridging ligand, etc., may be added. Examples of compounds that can act as bridging ligands include compounds having multiple hydroxyl groups, isocyanate groups, amino groups, ester groups, and amide groups.

[0075] [b] A method for carrying out a hydrolysis condensation reaction using a metal-containing compound is, for example, to carry out a hydrolysis condensation reaction of the [b] metal-containing compound in a solvent containing water. In this case, other compounds having hydrolyzable groups may be added as needed. The lower limit of the amount of water used in this hydrolysis condensation reaction is preferably 0.2 moles, more preferably 1 mole, and even more preferably 3 moles, relative to the hydrolyzable groups of the [b] metal-containing compound. The upper limit of the amount of water is preferably 20 moles, more preferably 15 moles, and even more preferably 10 moles.

[0076] [b] A method for carrying out a ligand exchange reaction using a metal-containing compound is, for example, a method of mixing the [b] metal-containing compound and the [a] organic acid. In this case, the mixing may be done in a solvent or without a solvent. In addition, a base such as triethylamine may be added to the above mixing as needed. The amount of the base to be added is, for example, 1 to 200 parts by mass per 100 parts by mass of the total amount of the [b] metal-containing compound and the [a] organic acid used.

[0077] [A] The solvent used in the synthesis reaction of the compound (hereinafter also referred to as "[d] solvent") is not particularly limited, and for example, the same solvent as those exemplified as the [C] solvent described later can be used. Among these, alcohol-based solvents, ether-based solvents, ester-based solvents and hydrocarbon-based solvents are preferred, alcohol-based solvents, ether-based solvents and ester-based solvents are more preferred, monoalcohol-based solvents, polyhydric alcohol partial ether-based solvents and polyhydric alcohol partial ether carboxylate-based solvents are even more preferred, and ethanol, n-propanol, isopropanol, 1-butanol, propylene glycol monoethyl ether and propylene glycol monoethyl ether acetate are particularly preferred.

[0078] [A] When solvent [d] is used in the synthesis reaction of compound [A], the solvent used may be removed after the reaction, but it may also be used as the [C] solvent of the resist underlayer film forming composition without being removed after the reaction.

[0079] [[B] Polymer] [B] A polymer has structural unit (I) and structural unit (II) (excluding structural unit that corresponds to structural unit (II) as structural unit (I)). [B] A polymer may contain other structural units other than structural unit (I) and structural unit (II) (hereinafter also simply referred to as "other structural units"). [B] A polymer may have one or more of each structural unit.

[0080] (Structural Unit (I)) Structural unit (I) is a structural unit represented by the following formula (1). [B] The presence of structural unit (I) in the polymer improves the fluidity of the composition, and as a result, the wafer edge removal and hump suppression of the resist underlayer film formed by the composition during the EBR process can be improved.

[0081] [ka]

[0082] In the above equation (1), R 1 R is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, either substituted or unsubstituted. 2 This is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms.

[0083] In this specification, "hydrocarbon group" includes linear hydrocarbon groups, alicyclic hydrocarbon groups, and aromatic hydrocarbon groups. Furthermore, "hydrocarbon group" includes saturated hydrocarbon groups and unsaturated hydrocarbon groups. "Linear hydrocarbon group" refers to a hydrocarbon group that does not contain a cyclic structure and consists only of a linear structure, and includes both straight-chain and branched-chain hydrocarbon groups. "Alicyclic hydrocarbon group" refers to a hydrocarbon group that contains only an alicyclic structure as its ring structure and does not contain an aromatic ring structure, and includes both monocyclic and polycyclic alicyclic hydrocarbon groups. However, an alicyclic hydrocarbon group does not need to consist only of an alicyclic structure; it may contain a linear structure as part of it. "Aromatic hydrocarbon group" refers to a hydrocarbon group that contains an aromatic ring structure as its ring structure. However, an aromatic hydrocarbon group does not need to consist only of an aromatic ring structure; it may contain a linear or alicyclic structure as part of it.

[0084] R 1 or R 2 Examples of unsubstituted monovalent hydrocarbon groups having 1 to 20 carbon atoms include unsubstituted monovalent linear hydrocarbon groups having 1 to 20 carbon atoms, unsubstituted monovalent alicyclic hydrocarbon groups having 3 to 20 carbon atoms, and unsubstituted monovalent aromatic hydrocarbon groups having 6 to 20 carbon atoms.

[0085] Examples of unsubstituted monovalent chain hydrocarbon groups having 1 to 20 carbon atoms include alkyl groups such as methyl, ethyl, propyl, butyl, and pentyl groups; alkenyl groups such as ethenyl, propenyl, and butenyl groups; and alkynyl groups such as ethynyl, propynyl, and butynyl groups.

[0086] Examples of unsubstituted monovalent alicyclic hydrocarbon groups having 3 to 20 carbon atoms include cycloalkyl groups such as cyclopentyl and cyclohexyl groups, cycloalkenyl groups such as cyclopropenyl, cyclopentenyl, and cyclohexenyl groups, and bridged ring hydrocarbon groups such as norbornyl and adamantyl groups.

[0087] Examples of unsubstituted monovalent aromatic hydrocarbon groups having 6 to 20 carbon atoms include aryl groups such as phenyl and naphthyl groups, and aralkyl groups such as benzyl, phenethyl, and naphthylmethyl groups.

[0088] R 1 or R 2 Examples of substituents in this compound include monovalent chain hydrocarbon groups having 1 to 10 carbon atoms, halogen atoms such as fluorine, chlorine, bromine, and iodine, alkoxy groups such as methoxy, ethoxy, and propoxy groups, alkoxycarbonyl groups such as methoxycarbonyl and ethoxycarbonyl groups, alkoxycarbonyloxy groups such as methoxycarbonyloxy and ethoxycarbonyloxy groups, acyl groups such as formyl, acetyl, propionyl, and butyryl groups, cyano groups, nitro groups, and hydroxyl groups.

[0089] R 1 Preferably, the group is a hydrogen atom or a substituted or unsubstituted monovalent chain hydrocarbon group having 1 to 20 carbon atoms; more preferably, a hydrogen atom or an unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms; and even more preferably, a hydrogen atom or a methyl group.

[0090] R 2 Preferably, the substituted C1-C20 monovalent linear hydrocarbon group is preferred, more preferably a fluorine atom-substituted C1-C20 monovalent linear hydrocarbon group is preferred, and even more preferably a hexafluoroisopropyl group, a 2,2,2-trifluoroethyl group, or a 3,3,4,4,5,5,6,6-octafluorohexyl group is preferred. In this case, the wafer edge removal and hump suppression properties of the resist underlayer film formed by the composition during the EBR process can be further improved. In this specification, "fluorine atom-substituted C1-C20 monovalent linear hydrocarbon group" means a linear hydrocarbon group in which some or all of the hydrogen atoms are substituted with fluorine atoms.

[0091] [B] The lower limit of the content of structural unit (I) in the total structural units constituting the polymer is preferably 10 mol%, more preferably 20 mol%, and even more preferably 30 mol%. The upper limit of the above content is preferably 90 mol%, more preferably 80 mol%, and even more preferably 70 mol%. When the content of structural unit (I) is within the above range, the wafer edge removal and hump suppression properties of the resist underlayer film formed by the composition during the EBR process can be further improved.

[0092] (Structural Unit (II)) Structural unit (II) is a structural unit represented by the following formula (2). By having structural unit (II) in the polymer [B], the compatibility with compound [A] and affinity with the substrate can be improved, and as a result, the coating properties of the composition can be improved.

[0093] [ka]

[0094] In equation (2) above, R 3 R is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, either substituted or unsubstituted. L is a single bond or a divalent linking group. Ar is a group obtained by removing (n+1) hydrogen atoms from an aromatic ring having 6 to 20 members, either substituted or unsubstituted. 4 R is a monovalent hydroxyalkyl group or hydroxyl group having 1 to 10 carbon atoms. n is an integer from 0 to 8. If n is 2 or greater, multiple R 4 They are the same or different.

[0095] R 3 Examples of unsubstituted monovalent hydrocarbon groups having 1 to 20 carbon atoms in the above formula (1) include R 1 Examples include groups similar to those exemplified as unsubstituted monovalent hydrocarbon groups having 1 to 20 carbon atoms in the above.

[0096] R 3 Examples of substituents in the above formula (1) include R 1Examples of substituents in the above include groups similar to those exemplified.

[0097] R 3 Preferably, the group is a hydrogen atom or a substituted or unsubstituted monovalent chain hydrocarbon group having 1 to 20 carbon atoms; more preferably, a hydrogen atom or an unsubstituted monovalent chain hydrocarbon group having 1 to 20 carbon atoms; and even more preferably, a hydrogen atom or a methyl group.

[0098] Examples of divalent linking groups in L include divalent hydrocarbon groups having 1 to 10 carbon atoms, such as -COO-, -CO-, -O-, and -CONH-.

[0099] A single bond is preferred for L.

[0100] Examples of unsubstituted aromatic rings with 6 to 20 members in Ar include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, indene, and pyrene rings, and aromatic heterocyclic rings such as furan, pyrrole, thiophene, phosphole, pyrazole, oxazole, isoxazole, thiazole, pyridine, pyrazine, pyrimidine, pyridazine, and triazine rings. Among these, aromatic hydrocarbon rings are preferred. In this specification, "number of members" refers to the number of atoms constituting the ring, and in the case of polycyclic rings, it refers to the number of atoms constituting the polycyclic ring.

[0101] Examples of substituents in Ar include R in formula (1) above. 1 Similar groups as those exemplified as substituents in [the relevant section] can be cited. However, R, which will be discussed later, can also be cited. 4 This is not considered a substituent in Ar.

[0102] As for Ar, a group obtained by removing (n+1) hydrogen atoms from an unsubstituted aromatic ring with 6 to 20 members is preferred, a group obtained by removing (n+1) hydrogen atoms from an unsubstituted aromatic hydrocarbon ring with 6 to 20 members is more preferred, and a group obtained by removing (n+1) hydrogen atoms from an unsubstituted benzene ring is even more preferred.

[0103] R 4In this context, a monovalent hydroxyalkyl group having 1 to 10 carbon atoms is a group in which some or all of the hydrogen atoms of a monovalent alkyl group having 1 to 10 carbon atoms are replaced by a hydroxyl group.

[0104] R 4 Preferably, a monovalent hydroxyalkyl group having 1 to 10 carbon atoms is preferred, a monovalent monohydroxyalkyl group having 1 to 10 carbon atoms is more preferred, and a monohydroxymethyl group is even more preferred. 4 The presence of the above-mentioned group makes it possible to further improve the flatness of the resist underlayer film formed by the composition.

[0105] n is preferably 1 to 5, more preferably 1 to 3, even more preferably 1 or 2, and particularly preferably 1.

[0106] [B] The lower limit of the content of structural unit (II) in the total structural units constituting the polymer is preferably 10 mol%, more preferably 20 mol%, and even more preferably 30 mol%. The upper limit of the above content is preferably 90 mol%, more preferably 80 mol%, and even more preferably 70 mol%. When the content of structural unit (II) is within the above range, the coating properties of the composition can be further improved.

[0107] (Other structural units) Other structural units include, for example, structural units derived from (meth)acrylic acid esters, structural units derived from (meth)acrylic acid, and structural units derived from acenaphthylene compounds.

[0108] [B]When the polymer has other structural units, the upper limit of the proportion of other structural units to the total structural units constituting the polymer is preferably 20 mol%, and more preferably 5 mol%.

[0109] [B] The lower limit of Mw for the polymer is preferably 1,000, more preferably 2,000, even more preferably 3,000, and particularly preferably 3,500. The upper limit of Mw is preferably 100,000, more preferably 50,000, even more preferably 30,000, and particularly preferably 20,000. By setting the Mw of the polymer within the above range, in addition to the coating properties of the composition, the wafer edge removal and hump suppression properties of the resist underlayer film formed by the composition during the EBR process can be improved.

[0110] [B] The upper limit of the Mw / Mn of the polymer is preferably 5, more preferably 3, and even more preferably 2.5. The lower limit of the above Mw / Mn is usually 1, and preferably 1.2.

[0111] The lower limit of the content of the [B] polymer in the composition is preferably 0.00001 parts by mass, more preferably 0.00005 parts by mass, even more preferably 0.0001 parts by mass, and particularly preferably 0.001 parts by mass, per 10 parts by mass of the [A] compound. The upper limit of the above content is preferably 2 parts by mass, more preferably 1.5 parts by mass, even more preferably 1 part by mass, and particularly preferably 0.8 parts by mass. By having the [B] polymer content within the above range, the coating properties of the composition, as well as the wafer edge removal and hump suppression properties of the resist underlayer film formed by the composition during the EBR process, can be improved.

[0112] ([B] Method for synthesizing polymers) [B] The polymer can be synthesized by polymerizing, for example, a monomer that gives structural unit (I), a monomer that gives structural unit (II), and a monomer that gives other structural units as needed, in amounts that constitute a predetermined content ratio, using a known method.

[0113] [[C] Solvent] The solvent [C] is not particularly limited as long as it is capable of dissolving or dispersing at least the compound [A], the polymer [B], and other optional components. The composition may contain one or more [C] solvents.

[0114] [C] Examples of solvents include organic solvents. Examples of organic solvents include alcohol-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, nitrogen-containing solvents, etc.

[0115] Examples of alcohol-based solvents include monoalcohol-based solvents such as methanol, ethanol, n-propanol, isopropanol, and 1-butanol, and polyhydric alcohol-based solvents such as ethylene glycol, 1,2-propylene glycol, triethylene glycol, and tripropylene glycol.

[0116] Examples of ketone solvents include linear ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, and 2-heptanone, and cyclic ketone solvents such as cyclohexanone.

[0117] Examples of ether-based solvents include linear ether solvents such as n-butyl ether, polyhydric alcohol ether solvents such as tetrahydrofuran and 1,4-dioxane, and polyhydric alcohol partial ether solvents such as propylene glycol monoethyl ether, tripropylene glycol monomethyl ether, and tetraethylene glycol monomethyl ether.

[0118] Examples of ester solvents include carbonate solvents such as diethyl carbonate, acetic acid monoester solvents such as methyl acetate, ethyl acetate, and butyl acetate, lactone solvents such as γ-butyrolactone, polyhydric alcohol partial ether carboxylate solvents such as diethylene glycol monomethyl ether acetate and propylene glycol monomethyl ether acetate, and lactate ester solvents such as methyl lactate and ethyl lactate.

[0119] Examples of nitrogen-containing solvents include linear nitrogen-containing solvents such as N,N-dimethylacetamide and cyclic nitrogen-containing solvents such as N-methylpyrrolidone.

[0120] Other examples include aromatic solvents such as toluene, xylene, and mesitylene.

[0121] [C] The solvent is preferably an ether-based solvent and / or an ester-based solvent, more preferably a polyhydric alcohol partial ether-based solvent and / or a polyhydric alcohol partial ether carboxylate-based solvent, and even more preferably propylene glycol monoethyl ether and / or propylene glycol monomethyl ether acetate.

[0122] The lower limit of the content of [C] solvent in relation to the total amount of [A] compound and [C] solvent is more preferably 50% by mass, more preferably 60% by mass, and more preferably 70% by mass. The upper limit of the above content is more preferably 99% by mass, more preferably 95% by mass, and more preferably 90% by mass. By setting the content of [C] solvent within the above range, the preparation of the composition can be facilitated and the coating properties can be improved.

[0123] [Other optional components] The composition may also contain other components besides those mentioned above, such as acid generators, polymer additives, polymerization inhibitors, surfactants, and the like.

[0124] If the composition contains other optional components, the amount of these components in the composition may be determined appropriately depending on the type and function of the other optional components used.

[0125] An acid generator is a compound that generates acid upon irradiation with radiation and / or heating. The composition may contain one or more acid generators.

[0126] Examples of acid generators include onium salt compounds and N-sulfonyloxyimide compounds.

[0127] The composition, by containing polymer additives, can further improve its coating properties and film continuity on substrates and organic underlayer films. The composition may contain one or more polymer additives.

[0128] Examples of polymer additives include (poly)oxyalkylene polymer compounds, fluorine-containing polymer compounds, and non-fluorine polymer compounds.

[0129] Examples of (poly)oxyalkylene polymer compounds include polyoxyalkylenes such as (poly)oxyethylene (poly)oxypropylene adducts, (poly)oxyalkyl ethers such as diethylene glycol heptyl ether, polyoxyethylene oleyl ether, polyoxypropylene butyl ether, polyoxyethylene polyoxypropylene-2-ethylhexyl ether, oxyethylene oxypropylene adducts to higher alcohols having 12 to 14 carbon atoms, (poly)oxyalkylene (alkyl)aryl ethers such as polyoxypropylene phenyl ether and polyoxyethylene nonylphenyl ether, and alkylene oxyalkylenes to acetylene alcohols such as 2,4,7,9-tetramethyl-5-decine-4,7-diol, 2,5-dimethyl-3-hexine-2,5-diol, and 3-methyl-1-butyne-3-ol. Examples include acetylene ethers obtained by addition polymerization of sides, (poly)oxyalkylene fatty acid esters such as diethylene glycol oleate, diethylene glycol laurylate, and ethylene glycol distearate, (poly)oxyalkylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monolaurate and polyoxyethylene sorbitan trioleate, (poly)oxyalkylene alkyl (aryl) ether sulfate salts such as polyoxypropylene methyl ether sodium sulfate and polyoxyethylene dodecylphenol ether sodium sulfate, (poly)oxyalkylene alkyl phosphate esters such as (poly)oxyethylene stearyl phosphate, and (poly)oxyalkylene alkylamines such as polyoxyethylene laurylamine.

[0130] Examples of fluorine-containing polymer compounds include the compounds described in Japanese Patent Publication No. 2011-89090. Examples of fluorine-containing polymer compounds include compounds containing repeating units derived from a (meth)acrylate compound having a fluorine atom and repeating units derived from a (meth)acrylate compound having two or more (preferably five or more) alkylene oxy groups (preferably ethylene oxy groups, propylene oxy groups).

[0131] Examples of non-fluorinated polymer compounds include linear or branched alkyl(meth)acrylates such as lauryl(meth)acrylate, 2-ethylhexyl(meth)acrylate, n-butyl(meth)acrylate, t-butyl(meth)acrylate, isooctyl(meth)acrylate, isostearyl(meth)acrylate, and isononyl(meth)acrylate; alkoxyethyl(meth)acrylates such as methoxyethyl(meth)acrylate; alkylene glycol di(meth)acrylates such as ethylene glycol di(meth)acrylate and 1,3-butylene glycol di(meth)acrylate; hydroxyalkyl(meth)acrylates such as 2-hydroxyethyl(meth)acrylate, 2-hydroxypropyl(meth)acrylate, 2-hydroxybutyl(meth)acrylate, and 4-hydroxybutyl(meth)acrylate; dicyclopentenyloxyethyl(meth)acrylate; and nonylphenoxypolyethylene glycol (-(CH2CH2O) n Examples include compounds containing one or more repeating units derived from (meth)acrylate monomers such as (meth)acrylates (n=1~17) that have a structure.

[0132] The composition may have enhanced storage stability by containing polymerization inhibitors. The composition may contain one or more polymerization inhibitors.

[0133] Examples of polymerization inhibitors include hydroquinone compounds such as 4-methoxyphenol and 2,5-di-tert-butylhydroquinone, and nitroso compounds such as N-nitrosophenylhydroxylamine and its aluminum salt.

[0134] The composition, by containing a surfactant, can further improve its coating properties and film continuity on substrates and organic underlayer films. The composition may contain one or more surfactants.

[0135] Examples of commercially available surfactants include "Newcol 2320", "Newcol 714-F", "Newcol 723", "Newcol 2307", and "Newcol 2303 (all from Nippon Emulsifier Co., Ltd.), "Pionin D-1107-S", "Pionin D-1007", "Pionin D-1106-DIR", "New Calgen TG310", "New Calgen TG310", "Pionin D-6105-W", "Pionin D-6112", "Pionin D-6512" (all from Takemoto Oil & Fat Co., Ltd.), "Surfinol 420", "Surfinol 440", "Surfinol 465", "Surfinol 2502" (all from Nippon Air Products Co., Ltd.), "Megafuck F171", "Same F172", "Same F173", "Same F176", "Same F177", "Same F141", "Same F142", "Same F143", "Same F1 Examples include "44", "R30", "F437", "F475", "F479", "F482", "F562", "F563", "F780", "R-40", "DS-21", "RS-56", "RS-90", and "RS-72-K" (all from DIC Corporation), "Florard FC430", "FC431" (both from Sumitomo 3M Co., Ltd.), "Asahi Guard AG710", "Surflon S-382", "SC-101", "SC-102", "SC-103", "SC-104", "SC-105", and "SC-106" (all from AGC Inc.), "FTX-218", and "NBX-15" (from Neos Co., Ltd.).

[0136] [Method for preparing a composition for forming a resist underlayer film] The resist underlayer film forming composition can be prepared by mixing [A] compound, [B] polymer, [C] solvent, and optionally any other components in predetermined proportions, and preferably by filtering the resulting mixture through a membrane filter with a pore size of 0.5 μm or less.

[0137] [Coating Process] In the coating process, the resist underlayer-forming composition is applied to the substrate directly or indirectly. The method of applying the resist underlayer-forming composition is not particularly limited and can be carried out by any suitable method, such as rotary coating, casting coating, or roll coating. A coating film is formed as a result, and the resist underlayer is formed by the volatilization of the [C] solvent, etc.

[0138] Examples of substrates include metal or metalloid substrates such as silicon substrates, aluminum substrates, nickel substrates, chromium substrates, molybdenum substrates, tungsten substrates, copper substrates, tantalum substrates, and titanium substrates, with silicon substrates being preferred among these. The above substrate may also be a substrate on which a silicon nitride film, alumina film, silicon dioxide film, tantalum nitride film, titanium nitride film, etc., is formed.

[0139] The lower limit of the average thickness of the resist underlayer film formed is preferably 3 nm, more preferably 5 nm, and even more preferably 10 nm. The upper limit of the average thickness is preferably 500 nm, more preferably 200 nm, and even more preferably 50 nm. The method for measuring the average thickness is as described in the examples.

[0140] The method for manufacturing the semiconductor substrate preferably further includes a step of heating the coating film formed by the above coating step (hereinafter also referred to as the "heating step"). Heating the coating film promotes the formation of the resist underlayer film. More specifically, heating the coating film promotes the volatilization of the [C] solvent, etc.

[0141] The above-mentioned coating film is usually heated under atmospheric conditions, but may also be heated under a nitrogen atmosphere. The lower limit of the heating temperature is preferably 150°C, and more preferably 200°C. The upper limit of the above temperature is preferably 600°C, and more preferably 400°C. The lower limit of the heating time is preferably 15 seconds, and more preferably 30 seconds. The upper limit of the above time is preferably 1,200 seconds, and more preferably 600 seconds.

[0142] [Organic lower layer film formation process] In this process, prior to the resist pattern formation process, an organic underlayer film is formed directly or indirectly on the substrate having the resist underlayer film formed by the coating process.

[0143] An organic underlayer can be formed by coating with an organic underlayer-forming composition. Methods for forming an organic underlayer by coating with an organic underlayer-forming composition include, for example, directly or indirectly coating a substrate having the resist underlayer with the organic underlayer-forming composition, and then curing the resulting coating by heating or exposure. Examples of organic underlayer-forming compositions include JSR Corporation's "HM8006". The heating and exposure conditions can be appropriately determined depending on the type of organic underlayer-forming composition used.

[0144] [Silicon-containing film formation process] In this process, prior to the resist pattern formation process, a silicon-containing film is formed directly or indirectly on the substrate having the resist underlayer film formed by the coating process.

[0145] Examples of cases in which a silicon-containing film is indirectly formed on a substrate having the resist underlayer include cases where a surface modification film of the resist underlayer is formed on the resist underlayer.

[0146] Silicon-containing films can be formed by coating with a silicon-containing film-forming composition, chemical vapor deposition (CVD), atomic layer deposition (ALD), etc. A method for forming a silicon-containing film by coating with a silicon-containing film-forming composition includes, for example, directly or indirectly coating the silicon-containing film-forming composition onto the resist underlayer and curing the resulting coated film by exposure and / or heating. Commercially available silicon-containing film-forming compositions include, for example, "NFC SOG01," "NFC SOG04," and "NFC SOG080" (all manufactured by JSR Corporation). Silicon oxide films, silicon nitride films, silicon oxidnitride films, and amorphous silicon films can be formed by chemical vapor deposition (CVD) or atomic layer deposition (ALD).

[0147] [Resist pattern formation process] In this process, a resist pattern is formed directly or indirectly on the resist underlayer film. Examples of methods for performing this process include using a resist composition, using a nanoimprint method, or using a self-assembled composition. An example of indirectly forming a resist pattern on the resist underlayer film is when the semiconductor substrate manufacturing method includes the silicon-containing film formation step, and a resist pattern is formed on the silicon-containing film.

[0148] The method using the above-mentioned resist composition involves coating the resist composition so that the resist film to be formed has a predetermined thickness, and then pre-baking to volatilize the solvent in the coated film, thereby forming the resist film.

[0149] Examples of the above-mentioned resist compositions include positive or negative type chemically amplified resist compositions containing a radiation-sensitive acid generator, positive type resist compositions containing an alkali-soluble resin and a quinone diazide-based photosensitive agent, and negative type resist compositions containing an alkali-soluble resin and a crosslinking agent. In this process, commercially available resist compositions can also be used as is.

[0150] Next, the resist film formed above is exposed by selective radiation irradiation. The radiation used for exposure can be appropriately selected depending on the type of radiation-sensitive acid generator used in the resist composition. Examples include electromagnetic waves such as visible light, ultraviolet light, far ultraviolet light, X-rays, and gamma rays, as well as particle beams such as electron beams, molecular beams, and ion beams. Among these, far ultraviolet light is preferred, KrF excimer laser light (248 nm), ArF excimer laser light (193 nm), F2 excimer laser light (wavelength 157 nm), Kr2 excimer laser light (wavelength 147 nm), ArKr excimer laser light (wavelength 134 nm), or extreme ultraviolet light (wavelength 13.5 nm, hereinafter also referred to as "EUV") is more preferred, and KrF excimer laser light, ArF excimer laser light, or EUV is even more preferred.

[0151] After the exposure described above, post-baking can be performed to improve resolution, pattern profile, developability, etc. The temperature and time of this post-baking can be appropriately determined depending on the type of resist composition used, etc.

[0152] Next, the exposed resist film is developed with a developer to form a resist pattern. This development may be alkaline development or organic solvent development. In the case of alkaline development, examples of basic aqueous solutions include ammonia, triethanolamine, tetramethylammonium hydroxide (TMAH), and tetraethylammonium hydroxide. These basic aqueous solutions may also have appropriate amounts of water-soluble organic solvents such as methanol and ethanol, or surfactants added to them. In the case of organic solvent development, examples of the developer include the various organic solvents exemplified as the [C] solvent in the above-mentioned composition.

[0153] After development with the above-mentioned developer, the resist pattern is formed by washing and drying.

[0154] [Etching process] In this process, a pattern is formed on the resist underlayer film by etching using the resist pattern described above as a mask. The etching can be performed once or multiple times, i.e., sequentially using the pattern obtained by etching as a mask. However, from the viewpoint of obtaining a pattern with a better shape, multiple etchings are preferred. When multiple etchings are performed, the silicon-containing film, organic underlayer film, resist underlayer film, and substrate are etched sequentially in that order. Examples of etching methods include dry etching and wet etching. Among these, dry etching is preferred from the viewpoint of obtaining a better pattern shape on the substrate. For this dry etching, for example, a gas plasma such as oxygen plasma is used. A semiconductor substrate having a predetermined pattern is obtained by the above etching.

[0155] Dry etching can be performed, for example, using a known dry etching apparatus. The etching gas used for dry etching can be appropriately selected depending on the mask pattern, the elemental composition of the film to be etched, etc. Examples include fluorine-based gases such as CHF3, CF4, C2F6, C3F8, SF6; chlorine-based gases such as Cl2, BCl3; oxygen-based gases such as O2, O3, H2O; reducing gases such as H2, NH3, CO, CO2, CH4, C2H2, C2H4, C2H6, C3H4, C3H6, C3H8, HF, HI, HBr, HCl, NO, NH3, BCl3; and inert gases such as He, N2, Ar. These gases can also be used in mixtures. When etching a substrate using the pattern of the resist underlayer film as a mask, fluorine-based gases are usually used.

[0156] Method for forming a resist underlayer film The method for forming the resist underlayer film comprises a step of coating a resist underlayer film forming composition directly or indirectly onto a substrate. The resist underlayer film forming composition can preferably be one used in the semiconductor substrate manufacturing method described above. The coating step can preferably be one used in the semiconductor substrate manufacturing method described above. [Examples]

[0157] The following describes some examples. It should be noted that the following examples are representative examples of the present invention and should not be interpreted as narrowing the scope of the invention.

[0158] In this example, the concentrations of components other than the solvent in the mixture containing compound [A], the weight-average molecular weight (Mw) of the hydrolysis condensate in the mixture containing compound [A], the weight-average molecular weight (Mw) of polymer [B], and the average thickness of the film were measured by the following methods.

[0159] [[A] Concentration of components other than the solvent in a mixture containing the compound] The mass of the residue after calcining 0.5 g of a mixture containing compound [A] at 250°C for 30 minutes was measured, and the concentration (mass%) of components other than the solvent in the mixture containing compound [A] was calculated by dividing the mass of this residue by the mass of the mixture containing compound [A].

[0160] [Weight-average molecular weight (Mw) of hydrolysis condensates in a mixture containing compound [A]] Analysis was performed using GPC columns (two "AWM-H", one "AW-H", and two "AW2500" columns from Tosoh Corporation), with a flow rate of 0.3 mL / min, elution solvent being N,N-dimethylacetamide with LiBr (30 mM) and citric acid (30 mM), and a column temperature of 40°C. The results were measured by gel permeation chromatography (detector: differential refractometer) with monodisperse polystyrene as the standard.

[0161] [[B] Weight-average molecular weight (Mw) of polymers] The mass (Mw) of the polymer was measured by gel permeation chromatography (detector: differential refractometer) using monodisperse polystyrene as the standard, under analytical conditions of a flow rate of 1.0 mL / min, elution solvent: tetrahydrofuran, and column temperature: 40°C, using GPC columns (two "G2000HXL" columns, one "G3000HXL" column, and one "G4000HXL" column from Tosoh Corporation).

[0162] [Average thickness of the resist underlayer] The average thickness of the resist underlayer was determined by measuring the film thickness at nine arbitrary points spaced 5 cm apart, including the center of the resist underlayer, using a spectroscopic ellipsometer (JAWOOLLAM's "M2000D"), and then calculating the average of these film thicknesses.

[0163] <[A] Synthesis of Compounds> The compounds [m], [x], [d], and [C] used in the synthesis of compound [A] are shown below. In the following synthesis examples, unless otherwise specified, "parts by mass" refers to the value when the mass of compound [m] used is 100 parts by mass. Also, "molar ratio" refers to the value when the amount of substance of compound [m] used is 1. The concentrations (by mass) of components other than the solvent in the mixture containing compound [A] are also shown in Table 1.

[0164] The following compounds were used as the [m] compound. m-1: Tetra-n-propoxydirconium(IV) m-2: Tetra-n-butoxyzirconium(IV) m-3: Tetra-n-propoxyhafnium(IV) m-4: Tetraisopropoxytitanium (IV) m-5: Pentaethoxitantalum (V)

[0165] The following compounds were used as [x] compounds. x-1: Propionic acid x-2: Butyrate x-3: Isobutyric acid x-4: Methacrylic acid x-5:2-ethylhexanoic acid x-6: Acetylacetone x-7: Diethanolamine

[0166] [d] The following compounds were used as solvents. d-1: n-propanol d-2: Ethanol d-3: 1-butanol d-4: Isopropanol

[0167] [C] The following compounds were used as solvents. C-1: Propylene glycol monomethyl ether acetate C-2: Propylene glycol monoethyl ether

[0168] [Synthesis Example 1-1] (Synthesis of compound (A-1) [A]) Under a nitrogen atmosphere, compound (m-1) and solvent (d-1) (40 parts by mass) were added to a reaction vessel. Compound (x-1) (molar ratio 5) was added dropwise to the reaction vessel over 20 minutes while stirring at 50°C. The reaction was then carried out at 80°C for 3 hours. After the reaction was complete, the reaction vessel was cooled to below 30°C. The precipitate obtained by cooling was filtered off, washed with n-hexane (100 parts by mass), and then vacuum dried to obtain compound (A-1).

[0169] [Synthesis Example 1-2] (Synthesis of compound (A-2) [A]) Under a nitrogen atmosphere, compound (m-1) and solvent (d-1) (200 parts by mass) were added to a reaction vessel. Compound (x-2) (molar ratio 5) was added dropwise to the reaction vessel over 20 minutes while stirring at 50°C. The reaction was then carried out at 80°C for 3 hours. After the reaction was complete, the reaction vessel was cooled to below 30°C. 900 parts by mass of solvent (C-1) were added to the cooled reaction solution, and then solvent (d-1), the alcohol produced by the reaction, and excess solvent (C-1) were removed using an evaporator to obtain a mixture containing compound (A-2). [A] The concentration of components other than the solvent in the mixture containing compound (A-2) was 14% by mass.

[0170] [Synthesis Examples 1-10, 1-14] (Synthesis of compounds (A-10) and (A-14) of [A]) Compounds [A] (A-10) and (A-14) were obtained in the same manner as in Synthesis Example 1-1, except that the types and amounts of compound [m], compound [x], and solvent [d] shown in Table 1 below were used.

[0171] [Synthesis Examples 1-3 to 1-9 and 1-11 to 1-13] (Synthesis of compounds (A-3) to (A-9) and (A-11) to (A-13)) A mixture containing compounds (A-3) to (A-9) and (A-11) to (A-13) was obtained in the same manner as in Synthesis Example 1-2, except that the types and amounts of compound [m], compound [x], solvent [d], and solvent [C] shown in Table 1 below were used.

[0172] [Synthesis Example 1-15] (Synthesis of compound (A-15) [A]) Compound (m-4) was added to the reaction vessel under a nitrogen atmosphere. Compound (x-6) (molar ratio 2) was added dropwise over 30 minutes while stirring at room temperature (25°C to 30°C). The reaction was then carried out at 60°C for 2 hours. After the reaction was complete, the reaction vessel was cooled to below 30°C. The cooled reaction solution was diluted with solvent (d-4) (900 parts by mass). Water (molar ratio 2) was added dropwise over 10 minutes while stirring at room temperature (25°C to 30°C). The hydrolysis condensation reaction was then carried out at 60°C for 2 hours. After the hydrolysis condensation reaction was complete, the reaction vessel was cooled to below 30°C. After adding 1,000 parts by mass of solvent (C-2) to the cooled reaction solution, water, isopropanol, the alcohol produced by the reaction, water, and excess solvent (C-2) were removed using an evaporator to obtain a mixture containing compound (A-15). The concentration of components other than the solvent in the mixture containing compound (A-15) was 13% by mass. The Mw of compound (A-15) was 2,800.

[0173] [Synthesis Example 1-16] (Synthesis of compound (A-16) [A]) A mixture containing compound [A] (A-16) was obtained in the same manner as in Synthesis Example 1-15, except that the types and amounts of compound [m], compound [x], solvent [d], and solvent [C] shown in Table 1 below were used. The Mw of compound (A-16) was 1,600.

[0174] [Table 1]

[0175] <[B] Synthesis of polymers> [B] As polymers, polymers represented by the following formulas (B-1) to (B-10) and (b-1) (hereinafter also referred to as "polymers (B-1) to (B-10) and (b-1)") were synthesized by the following procedure.

[0176] [ka]

[0177] In the above formulas (B-1) to (B-10) and (b-1), the numbers attached to each structural unit indicate the content percentage (mol%) of that structural unit.

[0178] [Synthesis Example 2-1] (Synthesis of polymer (B-1)) 43.0 g of 1,1,1,3,3,3-hexafluoroisopropyl methacrylate and 57.0 g of vinylbenzyl alcohol were dissolved in 130 g of methyl isobutyl ketone, and 19.6 g of 2,2'-azobis(2-methylpropionic acid)dimethyl was added to prepare a monomer solution. In a reaction vessel, 70 g of methyl isobutyl ketone was placed under a nitrogen atmosphere and heated to 80°C. The monomer solution was added dropwise over 3 hours while stirring. The start of the dropwise addition was defined as the start time of the polymerization reaction, and the polymerization reaction was carried out for 6 hours, after which it was cooled to below 30°C. 300 g of propylene glycol acetate monomethyl ether was added to the reaction solution, and the methyl isobutyl ketone was removed by vacuum concentration to obtain a propylene glycol acetate monomethyl ether solution of polymer (B-1). The Mw of polymer (B-1) was 4,200.

[0179] [Synthesis Examples 2-2 to 2-11] (Synthesis of polymers (B-2) to (B-10) and (b-1)) Solutions of polymers (B-2) to (B-10) and (b-1) in propylene glycol monomethyl ether acetate were obtained in the same manner as in Synthesis Example 2-1, except that monomers giving each structural unit shown in formulas (B-2) to (B-10) and (b-1) in their respective content percentages (mol%) were used. The Mw of polymer (B-2) was 3,800, polymer (B-3) was 4,000, polymer (B-4) was 4,300, polymer (B-5) was 4,500, polymer (B-6) was 4,100, polymer (B-7) was 4,100, polymer (B-8) was 4,200, polymer (B-9) was 4,200, polymer (B-10) was 4,300, and polymer (b-1) was 4,100.

[0180] <Preparation of Composition> The following are the compounds [A], polymers [B], solvents [C], and other optional components used in the preparation of the composition.

[0181] [A] The compounds (A-1) to (A-16) synthesized above were used as compounds.

[0182] [B] As polymers, the polymers (B-1) to (B-10) and (b-1) synthesized above were used.

[0183] [C] In addition to (C-1) and (C-2) used in the synthesis of compound [A], the following compounds were used as solvents. C-3: Cyclohexanone C-4:2-heptanone C-5: Mesicylene C-6: Butyl acetate

[0184] [F] The following compounds were used as other optional components. F-1:4-Methoxyphenol F-2: Surfactant (NBX-15 from Neos Co., Ltd.) F-3: Surfactant (DIC Corporation's "F563")

[0185] [Example 1-1] Preparation of composition (J-1) As shown in Table 2 below, [A] Compound (A-1) was mixed with 0.05 parts by mass of [B] Polymer (B-1) and 90 parts by mass of [C] Solvent (C-3). The resulting solution was filtered through a polytetrafluoroethylene (PTFE) filter with a pore size of 0.2 μm to prepare composition (J-1). In Table 2 below, "-" next to [B] Polymer and [F] Other optional components indicates that [B] Polymer and [F] Other optional components were not used. The same applies hereafter.

[0186] [Examples 1-2] Preparation of composition (J-2) As shown in Table 2 below, a mixture containing compound [A] (A-2) and [C] (C-1) as a solvent were mixed so that, for every 10 parts by mass of the non-solvent components in compound [A] (A-2), there were 0.05 parts by mass of polymer [B-1] and 90 parts by mass of solvent [C] (including the solvent [C] contained in the mixture containing compound [A]). The resulting solution was filtered through a polytetrafluoroethylene (PTFE) filter with a pore size of 0.2 μm to prepare composition (J-2).

[0187] [Examples 1-3 to 1-38] Preparation of compositions (J-3) to (J-38) Compositions (J-3) to (J-38) were prepared in the same manner as in Example 1-1 or Example 1-2, except that the types and contents of each component were as shown in Table 2 below.

[0188] [Comparative Examples 1-1 to 1-4] Preparation of compositions (j-1) to (j-4) Compositions (j-1) to (j-4) were prepared in the same manner as in Example 1-2, except that the types and contents of each component were as shown in Table 2 below.

[0189] [Table 2]

[0190] <Rating> The coating properties, wafer edge removal properties, and hump suppression properties of each of the compositions prepared above were evaluated according to the following method. The evaluation results are shown in Table 3 below.

[0191] [Formation of a substrate with an EBR-treated resist underlayer] Immediately after preparing the above composition, it was coated onto a silicon wafer (substrate) using a spin coater (CLEAN TRACK ACT8 from Tokyo Electron Ltd.) by rotary coating. While rotating the substrate at 1,500 rpm, the removal solution discharge nozzle was moved at a speed of 1 mm per second to a position 2 mm from the outer edge of the substrate to the center of the substrate. The removal solution (propylene glycol monomethyl ether acetate / propylene glycol monoethyl ether = 30 / 70, mass ratio) was discharged at a rate of 2 ml per second. After discharging the removal solution at a rate of 2 ml per second for 10 seconds at this position 2 mm from the outer edge of the substrate to the center of the substrate, the discharge of the removal solution was stopped, and the substrate was rotated at 1,500 rpm for 30 seconds. Next, the substrate was heated at 450°C for 60 seconds to obtain a substrate with a resist underlayer film with an average thickness of 30 nm.

[0192] [Coating properties] Regarding the coatability, the substrates with the resist underlayer film described above were visually inspected and evaluated as "A" (good) if no circular coating defects were observed, and as "B" (poor) if one or more circular coating defects were present.

[0193] [Wafer edge removeability] Regarding wafer edge removeability, the wafer periphery (up to 5 mm from the outer edge to the center of the substrate) of the resist underlayer film was observed using an optical microscope (10x magnification). If no removal unevenness was observed, it was evaluated as "A" (good), and if removal unevenness was observed, it was evaluated as "B" (poor). Figure 1A is an optical microscope image when no removal unevenness was observed in the wafer edge removeability evaluation, and Figure 1B is an optical microscope image when removal unevenness was observed in the wafer edge removeability evaluation.

[0194] [Hump suppression] Regarding hump suppression, the height change at a distance of up to 10 mm from the outer edge to the center of the substrate with the resist underlayer film was measured using a stylus-type step meter (KLA Alpha-Step D-600, stylus pressure 5 mg). With the height of the substrate without the resist underlayer film set to 0, a height of less than 40 nm was evaluated as "A" (good), a height of 40 nm or more but less than 50 nm was evaluated as "B" (somewhat good but poor), and a height of 50 nm or more was evaluated as "C" (poor).

[0195] [Table 3]

[0196] As can be seen from the results in Table 3, the compositions of the examples and the resist underlayer films formed from these compositions exhibited superior coating properties, wafer edge removal properties, and hump suppression compared to the comparative examples. [Industrial applicability]

[0197] The resist underlayer film formation composition of the present invention is excellent in terms of coating properties, wafer edge removal properties during the EBR process, and hump suppression properties. The semiconductor substrate manufacturing method of the present invention uses a resist underlayer film formation composition that is excellent in terms of coating properties, wafer edge removal properties during the EBR process, and hump suppression properties to form a resist underlayer film, so a high-quality semiconductor substrate can be efficiently manufactured. According to the resist underlayer film formation method of the present invention, since a resist underlayer film formation composition that is excellent in terms of coating properties, wafer edge removal properties during the EBR process, and hump suppression properties is used, a desired resist underlayer film can be efficiently formed. Therefore, these can be suitably used in the manufacture of semiconductor devices, etc., for which further miniaturization is expected to progress in the future.

Claims

1. Metal compounds and, A polymer having a first structural unit represented by the following formula (1) and a second structural unit represented by the following formula (2), solvent and It contains, The above metal compounds, Metal atoms belonging to groups 3 through 6 or 13 of the periodic table, Organic acids, hydroxy acid esters, β-diketones, β-ketoesters, or amine compounds A composition for forming a resist underlayer film, comprising the following: 【Chemistry 1】 (In formula (1), R １ R is a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms. ２ (This refers to a monovalent hydrocarbon group having 1 to 20 carbon atoms, either substituted or unsubstituted with a halogen atom.) 【Chemistry 2】 (In formula (2), R ３ L is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, either substituted or unsubstituted. L is a single bond or a divalent linking group. Ar is a group obtained by removing (n+1) hydrogen atoms from an aromatic ring having 6 to 20 members, either substituted or unsubstituted. ４ R is a monovalent hydroxyalkyl group or hydroxyl group having 1 to 10 carbon atoms. n is an integer from 1 to 8. If n is 2 or more, multiple R ４ They are either the same or different.

2. The resist underlayer film forming composition according to claim 1, wherein the content of the polymer relative to 10 parts by mass of the metal compound is 0.00001 parts by mass or more and 2 parts by mass or less.

3. R ２ The resist underlayer film forming composition according to claim 1 or claim 2, wherein is a halogen atom-substituted or unsubstituted monovalent chain hydrocarbon group having 1 to 20 carbon atoms.

4. R ２ The resist underlayer film forming composition according to claim 1 or claim 2, wherein is a substituted monovalent chain hydrocarbon group having 1 to 20 carbon atoms, and some or all of the hydrogen atoms of the chain hydrocarbon group are substituted with fluorine atoms.

5. The resist underlayer film forming composition according to claim 1 or claim 2, wherein n is an integer from 1 to 3 in formula (2).

6. In equation (2), at least one R ４ The resist underlayer film forming composition according to claim 1 or claim 2, wherein is a monohydroxyalkyl group.

7. The resist underlayer film forming composition according to claim 6, wherein the above monohydroxyalkyl group is a monohydroxymethyl group.

8. The resist underlayer film forming composition according to claim 1 or claim 2, wherein the content of the first structural unit in relation to the total structural units constituting the polymer is 10 mol% or more and 90 mol% or less.

9. The resist underlayer film forming composition according to claim 1 or claim 2, wherein the content of the second structural unit in relation to the total structural units constituting the polymer is 10 mol% or more and 90 mol% or less.

10. The resist underlayer film forming composition according to claim 1 or claim 2, wherein the metal atoms contained in the above metal compound belong to groups 3 to 5 of the periodic table.

11. The resist underlayer film forming composition according to claim 1 or claim 2, wherein the metal atom contained in the above metal compound belongs to Group 4 of the periodic table.

12. The resist underlayer film forming composition according to claim 1 or claim 2, wherein the content of the metal compound in the total components contained in the resist underlayer film forming composition is 2% by mass or more and 30% by mass or less.

13. A step of coating a substrate with a resist underlayer film formation composition, either directly or indirectly. The process of forming a resist pattern directly or indirectly on the resist underlayer film formed by the above coating process, A step of forming a pattern on the resist underlayer film by etching using the above resist pattern as a mask. Includes, The above resist underlayer film forming composition, Metal compounds and, A polymer having a first structural unit represented by the following formula (1) and a second structural unit represented by the following formula (2), solvent and It contains, The above metal compounds, Metal atoms belonging to groups 3 through 6 or 13 of the periodic table, Organic acids, hydroxy acid esters, β-diketones, β-ketoesters, or amine compounds A method for manufacturing a semiconductor substrate, comprising the above. 【Transformation 3】 (In formula (1), R １ is a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms. R ２ is a halogen atom-substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms.) 【Chemistry 4】 (In formula (2), R ３ L is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, either substituted or unsubstituted. L is a single bond or a divalent linking group. Ar is a group obtained by removing (n+1) hydrogen atoms from an aromatic ring having 6 to 20 members, either substituted or unsubstituted. ４ R is a monovalent hydroxyalkyl group or hydroxyl group having 1 to 10 carbon atoms. n is an integer from 1 to 8. If n is 2 or more, multiple R ４ They are either the same or different.

14. Prior to the above resist pattern formation step, A step of forming an organic underlayer film directly or indirectly on the resist underlayer film formed by the above coating process. A method for manufacturing a semiconductor substrate according to claim 13, further comprising:

15. Prior to the above resist pattern formation step, A step of forming a silicon-containing film directly or indirectly on the resist underlayer film formed by the above coating process. A method for manufacturing a semiconductor substrate according to claim 13 or claim 14, further comprising:

16. A process of coating a resist underlayer film formation composition directly or indirectly onto a substrate. Equipped with, The above resist underlayer film forming composition, Metal compounds and, A polymer having a first structural unit represented by the following formula (1) and a second structural unit represented by the following formula (2), solvent and It contains, The above metal compounds, Metal atoms belonging to groups 3 through 6 or 13 of the periodic table, Organic acids, hydroxy acid esters, β-diketones, β-ketoesters, or amine compounds A method for forming a resist underlayer film, comprising the following components. 【Transformation 5】 (In formula (1), R １ R is a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms. ２ (This refers to a monovalent hydrocarbon group having 1 to 20 carbon atoms, either substituted or unsubstituted with a halogen atom.) 【Transformation 6】 (In formula (2), R ３ L is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, either substituted or unsubstituted. L is a single bond or a divalent linking group. Ar is a group obtained by removing (n+1) hydrogen atoms from an aromatic ring having 6 to 20 members, either substituted or unsubstituted. ４ R is a monovalent hydroxyalkyl group or hydroxyl group having 1 to 10 carbon atoms. n is an integer from 1 to 8. If n is 2 or more, multiple R ４ They are either the same or different.

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