Resist underlayer film forming composition

Abstract

The present invention provides a composition for forming a resist underlayer film, the composition containing a compound represented by formula (1) and a solvent. (In formula (1), each X independently represents a halogen atom or a monovalent organic group that has at least one halogen atom; Y represents an n-valent group; and n represents an integer of 2 to 6.)

Description

Technical Field

[0001] The present invention relates to a resist underlayer film-forming composition that can be used particularly in state-of-the-art (ArF, EUV, EB, etc.) lithography processes in semiconductor manufacturing. Further, the present invention relates to a method for manufacturing a semiconductor substrate with a resist pattern to which a resist underlayer film obtained from the resist underlayer film-forming composition is applied, and a method for manufacturing a semiconductor device.

Background Art

[0002] Conventionally, in the manufacture of semiconductor devices, microfabrication by lithography using a resist composition has been performed. The microfabrication involves forming a thin film of a photoresist composition on a semiconductor substrate such as a silicon wafer, irradiating active light such as ultraviolet light through a mask pattern on which a device pattern is drawn thereon, developing, and etching the substrate using the obtained photoresist pattern as a protective film, thereby forming fine irregularities corresponding to the photoresist pattern on the substrate surface. In recent years, as semiconductor devices have become more highly integrated, the active light used has also evolved from the conventionally used i-line (wavelength 365 nm), KrF excimer laser (wavelength 248 nm), and ArF excimer laser (wavelength 193 nm) to the practical application of EUV light (wavelength 13.5 nm) or EB (electron beam) for state-of-the-art microfabrication. Along with this, poor resist pattern formation due to the influence of semiconductor substrates and the like has become a major problem. Therefore, in order to solve this problem, methods of providing a resist underlayer film between the resist and the semiconductor substrate have been widely studied.

[0003] Patent Document 1 discloses a lithography underlayer film-forming composition containing a naphthalene ring having a halogen atom. Patent Document 2 discloses a halogenated antireflection film. Patent Document 3 discloses a composition for forming a resist underlayer film.

Prior Art Documents

Patent Documents

[0004] [Patent Document 1] International Publication No. 2006 / 003850 [Patent Document 2] Japanese Patent Publication for International Application No. 2005-526270 [Patent Document 3] International Publication No. 2020 / 111068 [Summary of the Invention] [Problems to be Solved by the Invention]

[0005] As the characteristics required for the resist underlayer film, for example, there is no intermixing with the resist film formed on the upper layer (insoluble in the resist solvent), and the dry etching rate is faster than that of the resist film. In the case of lithography involving EUV exposure, the line width of the formed resist pattern is 32 nm or less, and the resist underlayer film for EUV exposure is formed with a thinner film thickness than before. When forming such a thin film, it was difficult to form a uniform film without defects because pinholes, aggregation, etc. were likely to occur due to the influence of the substrate surface, the polymer used, etc. On the other hand, when forming a resist pattern, in the negative development process of removing the unexposed portion of the resist film using a solvent (usually an organic solvent) that can dissolve the resist film and leaving the exposed portion of the resist film as a resist pattern, or in the positive development process of removing the exposed portion of the resist film using the solvent and leaving the unexposed portion of the resist film as a resist pattern, improving the adhesion of the resist pattern during development has become a major issue. In addition, it is required to suppress the deterioration of LWR (Line Width Roughness, line width roughness, fluctuation of line width (roughness)) during resist pattern formation, form a resist pattern having a good rectangular shape, and improve resist sensitivity.

[0006] The present invention aims to provide a resist underlayer forming composition for forming a resist underlayer capable of forming a desired resist pattern, a resist underlayer obtained from the resist underlayer forming composition, a method for manufacturing a semiconductor substrate having a patterned resist film using the resist underlayer, and a method for manufacturing a semiconductor device. [Means for solving the problem]

[0007] This invention encompasses the following: [1] A resist underlayer film forming composition comprising a compound represented by the following formula (1) and a solvent. [ka] (In formula (1), X independently represents a halogen atom or a monovalent organic group having at least one halogen atom. Y represents an n-valent group. n represents an integer from 2 to 6.) [2] The resist underlayer forming composition according to [1], wherein X is represented by the following formula (2). [ka] (In formula (2), X 1 X represents a monovalent hydrocarbon group having at least one halogen atom. 2 is, -O-CO- *1 (*1 is X 1 This represents a bond with -NR- (where R represents a monovalent organic group with 1 to 12 carbon atoms), or -S-. * represents a bond. [3] X 1 The resist underlayer film forming composition according to [2], wherein the alkyl group having 1 to 12 carbon atoms has at least one halogen atom. [4] A resist underlayer film forming composition according to any one of [1] to [3], wherein the number of constituent atoms of Y is 5 to 30. [5] A resist underlayer forming composition according to any one of [1] to [4], wherein Y comprises a carbon atom and at least one of a nitrogen atom and an oxygen atom. [6] A resist underlayer forming composition according to any one of [1] to [5], wherein Y is represented by the following formula (11) or (12). [ka] (In equations (11) and (12), * represents a coupling.) [7] A resist underlayer forming composition according to any one of [1] to [6], wherein the number of halogen atoms in X is 1 to 5. [8] In the compound represented by formula (1), when Y is the central part of the compound, at least one halogen atom of X is located at the terminal end of the compound, the resist underlayer forming composition according to any one of [1] to [7]. [9] The resist underlayer forming composition according to any one of [1] to [8], wherein the halogen atom is a fluorine atom or an iodine atom.

[10] A resist underlayer film forming composition according to any one of [1] to [9], further comprising a crosslinking agent.

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

[10] , further comprising an acid generator.

[12] A resist underlayer film which is a fired product of a coated film made from a resist underlayer film forming composition described in any of [1] to

[11] .

[13] A step of forming a resist underlayer film by applying a resist underlayer film forming composition described in any of [1] to

[11] onto a semiconductor substrate and baking it, The process of applying a resist onto the resist underlayer film and baking it to form a resist film, A step of exposing the semiconductor substrate coated with the resist underlayer film and the resist film, The process involves developing the resist film after exposure and patterning the resist film, A method for manufacturing a semiconductor substrate having a patterned resist film, including the following.

[14] A step of forming a resist underlayer on a semiconductor substrate, comprising a resist underlayer forming composition according to any one of [1] to

[11] , A step of forming a resist film on the resist underlayer film, A step of forming a resist pattern by irradiating the resist film with light or an electron beam and then developing it, A step of forming a patterned resist underlayer film by etching the resist underlayer film through the formed resist pattern, A process of processing a semiconductor substrate with the patterned resist underlayer film, A method for manufacturing a semiconductor device, including the method described above. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a resist underlayer forming composition for forming a resist underlayer film capable of forming a desired resist pattern, a resist underlayer film obtained from the resist underlayer forming composition, a method for manufacturing a semiconductor substrate having a patterned resist film using the resist underlayer film, and a method for manufacturing a semiconductor device. [Modes for carrying out the invention]

[0009] <Resist Underlayer Film Forming Composition> The resist underlayer film forming composition of the present invention comprises a compound represented by the following formula (1) and a solvent. The resist underlayer film forming composition may also contain other components such as crosslinking agents and acid generators.

[0010] <<Compound represented by formula (1)>>

[0011] [ka] (In formula (1), X independently represents a halogen atom or a monovalent organic group having at least one halogen atom. Y represents an n-valent group. n represents an integer from 2 to 6.)

[0012] << <x>>> Examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms, but fluorine atoms or iodine atoms are preferred. The halogen atom in the compound represented by formula (1) may be one type or multiple types, but it is preferable to have only one type because it makes it easier to manufacture the compound represented by formula (1).

[0013] n is preferably an integer between 2 and 5, and more preferably an integer between 3 and 4.

[0014] The number of carbon atoms in the monovalent organic group of X is not particularly limited, but is preferably 1 to 50, more preferably 1 to 30, and especially preferably 3 to 20.

[0015] The number of halogen atoms in X is not particularly limited; it may be 1 or 2 or more, but 1 to 5 is preferred, and 1 to 3 is more preferred.

[0016] The multiple X values ​​may be the same or different, but it is preferable that they be the same in that the compound represented by formula (1) is easy to produce.

[0017] X may or may not have an aromatic hydrocarbon ring. Examples of aromatic hydrocarbon rings include benzene rings, naphthalene rings, and anthracene rings.

[0018] Preferably, at least one of the halogen atoms in X is bonded to a carbon atom that is not a carbon atom constituting an aromatic hydrocarbon ring. Examples of such carbon atoms include carbon atoms constituting an alkyl group.

[0019] X is preferably represented by the following formula (2). [ka] (In formula (2), X 1 represents a monovalent hydrocarbon group having at least one halogen atom. X 2 is -O-CO- *1 (*1 represents a bond with X 1 .), -NR- (R represents a monovalent organic group having 1 to 12 carbon atoms), or -S-. * represents a bond.)

[0020] X 1 The number of carbon atoms in the hydrocarbon group of X is not particularly limited, but is preferably 1 to 20, more preferably 1 to 12, and particularly preferably 1 to 6.

[0021] X 1 Examples of the hydrocarbon group in X include an aromatic hydrocarbon group and a non-aromatic hydrocarbon group.

[0022] X 1 is preferably an alkyl group having from 1 to 12 carbon atoms and having at least one halogen atom, and more preferably an alkyl group having from 1 to 6 carbon atoms and having at least one halogen atom. The alkyl group having from 1 to 12 carbon atoms and having at least one halogen atom is, in other words, an alkyl group having from 1 to 12 carbon atoms in which at least one hydrogen atom is substituted with a halogen atom, and is also referred to as a halogenated alkyl group having from 1 to 12 carbon atoms. Examples of such alkyl halides include, when the halogen atom is a fluorine atom, trifluoromethyl group, 2,2,2-trifluoroethyl group, perfluoroethyl group, 3,3,3-trifluoropropyl group, 2,2,3,3,3-pentafluoropropyl group, 2,2,3,3-tetrafluoropropyl group, 2,2,2-trifluoro-1-(trifluoromethyl)ethyl group, perfluoropropyl group, 4,4,4-trifluorobutyl group, 3,3,4,4,4-pentafluorobutyl group, 2 Examples include 2,3,3,4,4,4-heptafluorobutyl group, perfluorobutyl group, 2,2,3,3,4,4,5,5,5-nonanafluoropentyl group, 2,2,3,3,4,4,5,5-octafluoropentyl group, perfluoropentyl group, 2,2,3,3,4,4,5,5,6,6,6-undecafluorohexyl group, 2,2,3,3,4,4,5,5,6,6-decafluorohexyl group, 3,3,4,4,5,5,6,6,6-nonanafluorohexyl group, and perfluorohexyl group. Furthermore, examples of halogenated alkyl groups, when the halogen atom is a chlorine atom, include monochloromethyl group, 1-chloroethyl group, 2-chloroethyl group, 2-chloroisobutyl group, 1,2-dichloroethyl group, 1,3-dichloroisopropyl group, 2,3-dichloro-t-butyl group, and 1,2,3-trichloropropyl group. Furthermore, examples of halogenated alkyl groups, when the halogen atom is a bromine atom, include bromomethyl group, 1-bromoethyl group, 2-bromoethyl group, 2-bromoisobutyl group, 1,2-dibromoethyl group, 1,3-dibromoisopropyl group, 2,3-dibromo-t-butyl group, 1,2,3-tribromopropyl group, iodomethyl group, 1-iodoethyl group, 2-iodoethyl group, 2-iodoisobutyl group, and 1,2-diiodoethyl group. Furthermore, examples of alkyl halides, when the halogen atom is an iodine atom, include iodomethyl group, 1-iodoethyl group, 2-iodoethyl group, 2-iodoisobutyl group, 1,2-diiodoethyl group, 1,3-diiodoisopropyl group, 2,3-diiodo-t-butyl group, and 1,2,3-triiodopropyl group.

[0023] X 2 Because the compound represented by formula (1) is easy to produce, -O-CO- *1 (*1 is X 1 It is preferable that it represents a coupling with ( ).

[0024] The R in -NR- is not particularly limited as long as it is a monovalent organic group having 1 to 12 carbon atoms, but examples include hydrocarbon groups having 1 to 12 carbon atoms, and hydrocarbon groups having 1 to 12 carbon atoms having at least one halogen atom. Examples of hydrocarbon groups include alkyl groups. Specific examples of alkyl groups with 1 to 12 carbon atoms having at least one halogen atom are the same as above. R is, for example, *-X 2 -X 1 X that constitutes 1 It is the same as this.

[0025] << <y>>> Y is not particularly limited as long as it is an n-valent group, but the number of constituent atoms of Y is, for example, 5 to 30. Y, for example, has a carbon atom and at least one of a nitrogen atom and an oxygen atom. Y is preferably represented by the following formulas (11), (12), or (13), and more preferably by formula (11) or (12).

[0026] [ka] (In equations (11) to (13), * represents a bond. R 1 R represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. 2 (This represents a single bond or an alkylene group with 1 to 3 carbon atoms.)

[0027] Note that when Y is expressed by equation (11), n ​​in equation (1) is usually 3. When Y is expressed by equation (12), n in equation (1) is usually 4. When Y is expressed by equation (13), n in equation (1) is usually 3.

[0028] R 1 and R 2 For example, R 1 is a hydrogen atom, and R 2 A combination where R is a single bond. 1 is an ethyl group, R 2 Examples include combinations in which the group is a methylene group.

[0029] In the compound represented by formula (1), if Y is the central part of the compound, then, for example, at least one of the halogen atoms of X is located at the terminal end of the compound.

[0030] In the resist underlayer film forming composition, there may be one compound represented by formula (1) or two or more compounds. In the method for producing the compound represented by formula (1) described later, a mixture of two or more compounds represented by formula (1) may be obtained, and such a mixture may be used in the resist underlayer film forming composition.

[0031] The molecular weight of the compound represented by formula (1) is not particularly limited, but is preferably 200 to 2,000, more preferably 300 to 1,500, and particularly preferably 500 to 1,300.

[0032] <<Method for producing the compound represented by formula (1)>> There are no particular limitations on the method for producing the compound represented by formula (1), but one example is a method of reacting a compound represented by the following formula (1A) with a compound represented by the following formula (1B).

[0033] [ka] (In equations (1A) and (1B), X, Y, and n are equivalent to X, Y, and n in equation (1), respectively.)

[0034] As a compound represented by formula (1B), for example, the compound represented by the following formula (1B-1) is preferred.

[0035] [ka] (In formula (1B-1), X 1 , and X 2 These are the X in equation (2), respectively. 1 , and X 2 (This is synonymous with...)

[0036] When producing the compound represented by formula (1), the molar ratio of the compound represented by formula (1A) to the compound represented by formula (1B) (formula (1A):formula (1B)) can range from 1:n to 1:2n, where n is the n in formula (1A).

[0037] The compound represented by formula (1A) may be manufactured or commercially available. Examples of commercially available products include triglycidyl isocyanuric acid (manufactured by Nissan Chemical Corporation), 1,3,4,6-tetraglycidyl glycoluryl (manufactured by Shikoku Chemicals Co., Ltd.), Denacol EX-614B (sorbitol polyglycidyl ether, manufactured by Nagase ChemteX Corporation), Denacol EX-313 (glycerol polyglycidyl ether, manufactured by Nagase ChemteX Corporation), Denacol EX-512 (polyglycerol polyglycidyl ether, manufactured by Nagase ChemteX Corporation), Denacol EX-321 (trimethylolpropane polyglycidyl ether, manufactured by Nagase ChemteX Corporation), and Denacol EX-321L (trimethylolpropane polyglycidyl ether, manufactured by Nagase ChemteX Corporation). These may be compounds represented by a single formula (1A), mixtures of two or more compounds represented by formula (1A), or mixtures of one or more compounds represented by formula (1A) with other compounds.

[0038] One example of the reaction mode for producing the compound represented by formula (1) is the addition reaction between a glycidyl group and a carboxyl group. In this case, quaternary ammonium salts, phosphonium salts, etc., may be used as catalysts. Examples of quaternary ammonium salts include tetrabutylammonium tetrafluoroborate, tetrabutylammonium hexafluorophosphate, tetrabutylammonium hydrogen sulfate, tetraethylammonium tetrafluoroborate, tetraethylammonium p-toluenesulfonate, N,N-dimethyl-N-benzylanilinium hexafluoroantimonate, N,N-dimethyl-N-benzylanilinium tetrafluoroborate, N,N-dimethyl-N-benzylpyridinium hexafluoroantimonate, N,N-diethyl-N-benzyltrifluoromethanesulfonate, N,N-dimethyl-N-(4-methoxybenzyl)pyridinium hexafluoroantimonate, and N,N-diethyl-N-(4-methoxybenzyl)toluidinium hexafluoroantimonate. Examples of phosphonium salts include triphenylbenzylphosphonium chloride, triphenylbenzylphosphonium bromide, triphenylbenzylphosphonium iodide, triethylbenzylphosphonium chloride, and tetrabutylphosphonium bromide. The amount of catalyst used is not particularly limited.

[0039] The method for producing the compound represented by formula (1) may be carried out in the presence of an organic solvent or without a solvent. Examples of organic solvents that can be used include ethers, alkylene glycol monoalkyl ethers, alkylene glycol dialkyl ethers, esters, and ketones. Examples of ethers include diethyl ether, tetrahydrofuran, tetrahydropyran, diisopropyl ether, diphenyl ether, anisole, phenethole, and guaiacol; and alkylene glycols include ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, and triethylene glycol. Examples of alkylene glycol monoalkyl ethers include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, butylene glycol monomethyl ether, butylene glycol monoethyl ether, diethylene glycol monomethyl ether, and diethylene glycol monoethyl ether. Examples of alkylene glycol dialkyl ethers include ethylene glycol dimethyl ether (DME), ethylene glycol diethyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, butylene glycol dimethyl ether, butylene glycol diethyl ether, diethylene glycol dimethyl ether, and diethylene glycol diethyl ether. Examples of esters include methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl propionate, ethyl propionate, propyl propionate, butyl propionate, methyl formate, ethyl formate, propyl formate, butyl formate, methyl benzoate, ethyl benzoate, propyl benzoate, and butyl benzoate. Examples of ketones include acetone, acetylacetone, methyl ethyl ketone, cyclohexanone, and cyclopentanone.

[0040] The reaction temperature in the method for producing the compound represented by formula (1) is not particularly limited, but examples include 20°C to 60°C. The reaction time in the method for producing the compound represented by formula (1) is not particularly limited, but for example, it can range from 1 hour to 72 hours.

[0041] In the method for producing the compound represented by formula (1), a single compound represented by formula (1) may be obtained, a mixture of two or more compounds represented by formula (1) may be obtained, or a mixture of one or more compounds represented by formula (1) and other compounds may be obtained. If the product obtained by the method for producing the compound represented by formula (1) is a mixture, the mixture may be purified and used in the preparation of the resist underlayer film forming composition, or the mixture may be used in the preparation of the resist underlayer film forming composition without purification.

[0042] The content of the compound represented by formula (1) in the resist underlayer film forming composition is not particularly limited, but from the viewpoint of solubility, it is preferably 0.1% to 50% by mass, and more preferably 0.1% to 10% by mass, relative to the entire resist underlayer film forming composition.

[0043] <Solvent> The solvent used in the resist underlayer film forming composition is not particularly limited as long as it can uniformly dissolve the solid components at room temperature, but organic solvents commonly used in semiconductor lithography process chemicals are preferred. Specifically, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, propylene glycol propyl ether acetate, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, cyclo Examples include heptanone, 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. These solvents can be used individually or in combination of two or more.

[0044] Among these solvents, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, ethyl lactate, butyl lactate, and cyclohexanone are preferred. Propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate are particularly preferred.

[0045] <Crosslinking agent> The crosslinking agent included as an optional component in the resist underlayer film forming composition has a functional group that reacts with the secondary hydroxyl group of the compound represented by formula (1). Examples of crosslinking agents include hexamethoxymethylmelamine, tetramethoxymethylbenzoguanamine, 1,3,4,6-tetrakis(methoxymethyl)glycoluryl (tetramethoxymethylglycoluryl) (POWDERLINK® 1174), 1,3,4,6-tetrakis(butoxymethyl)glycoluryl, 1,3,4,6-tetrakis(hydroxymethyl)glycoluryl, 1,3-bis(hydroxymethyl)urea, 1,1,3,3-tetrakis(butoxymethyl)urea, and 1,1,3,3-tetrakis(methoxymethyl)urea.

[0046] Furthermore, the crosslinking agent may be a nitrogen-containing compound having 2 to 6 substituents represented by the following formula (1d) that bond to a nitrogen atom in one molecule, as described in International Publication No. 2017 / 187969.

[0047] [ka] (In formula (1d), R1 represents a methyl group or an ethyl group. * represents a bond that connects to a nitrogen atom.)

[0048] A nitrogen-containing compound having 2 to 6 substituents represented by formula (1d) in one molecule may be a glycoluryl derivative represented by the following formula (1E).

[0049] [ka] (In formula (1E), each of the four R1s independently represents a methyl group or an ethyl group, and R2 and R3 independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group.)

[0050] Examples of glycoluryl derivatives represented by formula (1E) include the compounds represented by the following formulas (1E-1) to (1E-6).

[0051] [ka]

[0052] A nitrogen-containing compound having 2 to 6 substituents represented by formula (1d) in one molecule can be obtained by reacting a nitrogen-containing compound having 2 to 6 substituents represented by the following formula (2d) that bond to a nitrogen atom in one molecule with at least one compound represented by the following formula (3d).

[0053] [ka] (In formulas (2d) and (3d), R1 represents a methyl group or an ethyl group, and R4 represents an alkyl group having 1 to 4 carbon atoms. * represents a bond that connects to a nitrogen atom.)

[0054] The glycoluryl derivative represented by formula (1E) is obtained by reacting a glycoluryl derivative represented by the following formula (2E) with at least one compound represented by formula (3d).

[0055] A nitrogen-containing compound having 2 to 6 substituents represented by formula (2d) in one molecule is, for example, a glycoluryl derivative represented by the following formula (2E).

[0056] [ka] (In formula (2E), R2 and R3 each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group, and R4 each independently represents an alkyl group having 1 to 4 carbon atoms.)

[0057] Examples of glycoluryl derivatives represented by formula (2E) include the compounds represented by formulas (2E-1) to (2E-4) below. Furthermore, examples of compounds represented by formula (3d) include the compounds represented by formulas (3d-1) and (3d-2) below.

[0058] [ka] [ka]

[0059] With regard to nitrogen-containing compounds having 2 to 6 substituents represented by formula (1d) bonded to the aforementioned nitrogen atom in one molecule, the full disclosure in WO2017 / 187969 is incorporated herein by reference.

[0060] When the aforementioned crosslinking agent is used, the content of the crosslinking agent is, for example, 1% to 50% by mass, preferably 5% to 30% by mass, relative to the compound represented by formula (1).

[0061] <Acid Generator> The acid generator included as an optional component in the resist underlayer film forming composition can be either a thermal acid generator or a photoacid generator, but it is preferable to use a thermal acid generator. Examples of the aforementioned hot acid generating agents include sulfonic acid compounds and 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 salt of p-phenolsulfonic acid), 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, and hydroxybenzoic acid.

[0062] Examples of the photoacid generators include onium salt compounds, sulfonimide compounds, and disulfonyldiazomethane compounds.

[0063] Examples of iodonium salt compounds include iodonium salt compounds such as diphenyliodonium hexafluorophosphate, diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoron-butanesulfonate, diphenyliodonium perfluoron-octanesulfonate, diphenyliodonium camphor sulfonate, bis(4-tert-butylphenyl)iodonium camphor sulfonate and bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate, and sulfonium salt compounds such as triphenylsulfonium hexafluoroantimonate, triphenylsulfonium nonafluoron-butanesulfonate, triphenylsulfonium camphor sulfonate and triphenylsulfonium trifluoromethanesulfonate.

[0064] Examples of sulfonimide compounds include N-(trifluoromethanesulfonyloxy)succinimide, N-(nonafluoron-butanesulfonyloxy)succinimide, N-(camphorsulfonyloxy)succinimide, and N-(trifluoromethanesulfonyloxy)naphthalimide.

[0065] Examples of disulfonyl diazomethane compounds include bis(trifluoromethylsulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, bis(phenylsulfonyl)diazomethane, bis(p-toluenesulfonyl)diazomethane, bis(2,4-dimethylbenzenesulfonyl)diazomethane, and methylsulfonyl-p-toluenesulfonyldiazomethane.

[0066] The aforementioned acid generating agent can be used by one type only, or by a combination of two or more types.

[0067] When the acid generator is used, the content of the acid generator is, for example, 0.1% to 50% by mass, preferably 1% to 30% by mass, relative to the crosslinking agent.

[0068] <Other ingredients> The resist underlayer film-forming composition is free from pinholes and striations, and surfactants can be added to further improve the coatability against surface unevenness. Examples of surfactants include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, and polyoxyethylene oleyl ether; polyoxyethylene alkyl allyl ethers such as polyoxyethylene octylphenol ether and polyoxyethylene nonylphenol ether; polyoxyethylene-polyoxypropylene block copolymers; sorbitan fatty acid esters such as sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, and sorbitan tristearate; and polyoxyethylene sorbitan monolaurate and polyoxyethylene sorbitan monopalmitate. Examples include nonionic surfactants such as polyoxyethylene sorbitan fatty acid esters like polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, and polyoxyethylene sorbitan tristearate; fluorine-based surfactants such as F-Top EF301, EF303, EF352 (manufactured by Tochem Products Co., Ltd., product name), Megafac F171, F173, R-30 (manufactured by Dainippon Ink, Inc., product name), Florard FC430, FC431 (manufactured by Sumitomo 3M Co., Ltd., product name), Asahi Guard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by Asahi Glass Co., Ltd., product name); and organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.). The amount of these surfactants added is usually 2.0% by mass or less, preferably 1.0% by mass or less, relative to the total solid content of the resist underlayer film-forming composition. These surfactants may be added individually or in combination of two or more types.

[0069] The non-volatile content of the resist underlayer film-forming composition, i.e., the components excluding the solvent, is, for example, 0.01% to 10% by mass.

[0070] <Underlying resist film> The resist underlayer film according to the present invention can be manufactured by applying the aforementioned resist underlayer film forming composition onto a semiconductor substrate and firing it. The resist underlayer film is a fired product of a coated film made from a resist underlayer film forming composition.

[0071] Examples of semiconductor substrates to which the resist underlayer film forming composition of the present invention is coated include silicon wafers, germanium wafers, and compound semiconductor wafers such as gallium arsenide, indium phosphide, gallium nitride, indium nitride, and aluminum nitride.

[0072] When using a semiconductor substrate with an inorganic film formed on its surface, the inorganic film is formed by, for example, ALD (atomic layer deposition), CVD (chemical vapor deposition), reactive sputtering, ion plating, vacuum deposition, or spin coating (spin-on-glass: SOG). Examples of the inorganic film include polysilicon films, silicon oxide films, silicon nitride films, BPSG (Boro-Phospho-Silicate Glass) films, titanium nitride films, titanium oxide nitride films, tungsten films, gallium nitride films, and gallium arsenide films.

[0073] The resist underlayer film forming composition of the present invention is applied to such a semiconductor substrate by an appropriate coating method such as a spinner or coater. Subsequently, the resist underlayer film is formed by baking using a heating means such as a hot plate. The baking conditions are appropriately selected from a bake temperature of 100°C to 400°C and a bake time of 0.3 minutes to 60 minutes. Preferably, the bake temperature is 120°C to 350°C and the bake time is 0.5 minutes to 30 minutes, and more preferably, the bake temperature is 150°C to 300°C and the bake time is 0.8 minutes to 10 minutes.

[0074] The thickness of the resist underlayer film formed can 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), or 0.003 μm (3 nm). The thickness ranges are 0.005μm (50nm), 0.004μm (4nm) to 0.05μm (50nm), 0.005μm (5nm) to 0.05μm (50nm), 0.003μm (3nm) to 0.03μm (30nm), 0.003μm (3nm) to 0.02μm (20nm), and 0.005μm (5nm) to 0.02μm (20nm). If the baking temperature is lower than the above range, crosslinking will be insufficient. On the other hand, if the baking temperature is higher than the above range, the resist underlayer film may decompose due to heat.

[0075] <Manufacturing method for semiconductor substrates having patterned resist films, manufacturing method for semiconductor devices> A method for manufacturing a semiconductor substrate having a patterned resist film includes at least the following steps: • A process of applying the resist underlayer film forming composition of the present invention onto a semiconductor substrate and baking it to form a resist underlayer film. • A process of applying a resist onto a resist underlayer and baking it to form a resist film. • The process of exposing a semiconductor substrate coated with a resist underlayer and a resist film. • The process of developing the resist film after exposure and patterning the resist film.

[0076] A method for manufacturing a semiconductor device includes at least the following steps: • A step of forming a resist underlayer film on a semiconductor substrate, comprising the resist underlayer film forming composition of the present invention. • Process of forming a resist film on top of the resist underlayer film. - A process of forming a resist pattern by irradiating the resist film with light or an electron beam and then developing it. The process of forming a patterned resist underlayer by etching the resist underlayer through the formed resist pattern, • Process of processing semiconductor substrates using a patterned resist underlayer film.

[0077] A method for manufacturing a semiconductor substrate having a patterned resist film and a method for manufacturing a semiconductor device follow the steps below, for example. Typically, the manufacturing process involves forming a photoresist layer on a resist underlayer film. The photoresist formed by coating and firing on the resist underlayer film using a known method is not particularly limited as long as it is sensitive to the light used for exposure. Both negative and positive photoresists can be used. Examples include positive photoresists consisting of novolac resin and 1,2-naphthoquinone diazide sulfonic acid ester, chemically amplified photoresists consisting of a binder having a group that decomposes with acid to increase the alkali dissolution rate and a photoacid generator, chemically amplified photoresists consisting of a low-molecular-weight compound that decomposes with acid to increase the alkali dissolution rate of the photoresist, an alkali-soluble binder and a photoacid generator, and chemically amplified photoresists consisting of a binder having a group that decomposes with acid to increase the alkali dissolution rate and a low-molecular-weight compound that decomposes with acid to increase the alkali dissolution rate of the photoresist and a photoacid generator, as well as resists containing metal elements. Examples include V146G from JSR Corporation, APEX-E from Cyprey Corporation, PAR710 from Sumitomo Chemical Co., Ltd., and AR2772 and SEPR430 from Shin-Etsu Chemical Co., Ltd. Additionally, 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).

[0078] 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 While so-called resist compositions and metal-containing resist compositions such as those described in JP 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., can be used, they are not limited to these.

[0079] Examples of resist compositions include the following compositions.

[0080] A photosensitive or radiation-sensitive resin composition comprising resin A having repeating units with acid-degradable groups whose polar groups are protected by protective groups that are removed by the action of an acid, and a compound represented by the following general formula (21).

[0081] [ka] In general formula (21), m represents an integer from 1 to 6. R1 and R2 each independently represent a fluorine atom or a perfluoroalkyl group. L1 represents -O-, -S-, -COO-, -SO2-, or -SO3-. L2 represents an alkylene group or single bond which may have substituents. W1 represents a cyclic organic group which may have substituents. M + This represents a cation.

[0082] 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 the 3rd to 7th periods of groups 3 to 15 of the periodic table.

[0083] 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) that includes an acid-dissociable group, and an acid generator.

[0084] [ka] (In formula (31), Ar is a group obtained by removing (n+1) hydrogen atoms from an arene with 6 to 20 carbon atoms. 1 R is a hydroxyl group, a sulfanyl group, or a monovalent organic group having 1 to 20 carbon atoms. n is an integer from 0 to 11. If n is 2 or greater, multiple R groups are used. 1 They are the same or different. 2 R is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. In formula (32), R 3 This is a monovalent group having 1 to 20 carbon atoms that contains the above-mentioned acid-dissociable group. Z is a single bond, an oxygen atom, or a sulfur atom. R 4 (This is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.)

[0085] A resist composition containing a resin (A1) comprising structural units having a cyclic carbonate ester structure, structural units represented by the following formula, and structural units having an acid-unstable group, and an acid generator.

[0086] [ka] [In the formula, R 2 X represents an alkyl group having 1 to 6 carbon atoms, a hydrogen atom, or a halogen atom, which may have a halogen atom. 1 These are single bonds, -CO-O-*, or -CO-NR 4 -* represents a bond with -Ar, and 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 hydroxyl groups and carboxyl groups.

[0087] Examples of resist films include the following:

[0088] A resist film comprising a base resin containing repeating units represented by the following formula (a1) and / or repeating units represented by the following formula (a2), and repeating units that generate acid bonded to the polymer main chain upon exposure.

[0089] [ka] (In equations (a1) and (a2), R A Each of these is independently either a hydrogen atom or a methyl group. 1 and R 2 Each of these is independently a tertiary alkyl group having 4 to 6 carbon atoms. 3 Each of these is independently either a fluorine atom or a methyl group. m is an integer from 0 to 4. 1 This is a linking group having 1 to 12 carbon atoms, containing a single bond, a phenylene group or a naphthylene group, or at least one selected from an ester bond, a lactone ring, a phenylene group, and a naphthylene group. 2 (These are single bonds, ester bonds, or amide bonds.)

[0090] Examples of resist materials include the following:

[0091] A resist material comprising a polymer having repeating units represented by the following formula (b1) or formula (b2).

[0092] [ka] (In equations (b1) and (b2), R A X is a hydrogen atom or a methyl group. 1 X is a single bond or an ester group. 2 X 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 a portion 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 in X is replaced by 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 Each of these is independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, but at least one is a fluorine atom or a trifluoromethyl group. Also, Rf 1 and Rf 2 They may combine to form a carbonyl group. 1 ~R 5 Each of these is 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, and some or all of the hydrogen atoms of these groups may be substituted with a hydroxyl group, a carboxyl 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 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 sulfonic acid ester group. 1 and R 2 These may combine to form a ring with the sulfur atom to which they are bonded.

[0093] A resist material comprising a base resin containing a polymer containing repeating units represented by the following formula (a).

[0094] [ka] (In formula (a), R A R is a hydrogen atom or a methyl group. 1 R is a hydrogen atom or an acid-unstable group. 2 This is a linear, branched, or cyclic alkyl group having 1 to 6 carbon atoms, or a halogen atom other than bromine. 1 This is a linear, branched, or cyclic alkylene group having 1 to 12 carbon atoms, which may contain a single bond or a phenylene group, or an ester group or a lactone ring. 2 is -O-, -O-CH2-, or -NH-. m is an integer between 1 and 4. u is an integer between 0 and 3. However, m+u is an integer between 1 and 4.

[0095] A resist composition that generates acid upon exposure, and whose solubility in a developer changes due to the action of the acid, It contains a base component (A) whose solubility in the developer changes due to the action of acid, and a fluorine additive component (F) that is degradable in alkaline developer. The fluorine additive component (F) contains a fluororesin component (F1) having a constituent unit (f1) containing a base-dissociable group and a constituent unit (f2) containing a group represented by the following general formula (f2-r-1), wherein the fluorine additive component (F) contains a fluororesin component (F1).

[0096] [ka] [In formula (f2-r-1), Rf 21 Each of these is independently a hydrogen atom, an alkyl group, an alkoxy group, a hydroxyl group, a hydroxyalkyl group, or a cyano group. n'' is an integer from 0 to 2. * represents a bond.

[0097] The aforementioned constituent unit (f1) includes a constituent unit represented by the following general formula (f1-1) or a constituent unit represented by the following general formula (f1-2).

[0098] [ka] [In formulas (f1-1) and (f1-2), R is independently a hydrogen atom, a C1-C5 alkyl group, or a C1-C5 halogenated alkyl group. X is a divalent linking group that does not have an acid-dissociable site. A aryl X is a divalent aromatic cyclic group which may have substituents. 01 R is a single bond or a divalent linking group. 2 These are, independently, organic groups that contain a fluorine atom.

[0099] Examples of coatings, coating solutions, and coating compositions include the following:

[0100] A coating comprising a metal oxo-hydroxo network having organic ligands via metal-carbon bonds and / or metal-carboxylate bonds.

[0101] Inorganic oxo / hydroxo-based compositions.

[0102] A coating solution comprising an organic solvent; a first organometallic composition represented by the formula R z SnO (2-(z / 2)-(x / 2)) (OH) x (where 0 < z ≦ 2 and 0 < (z + x) ≦ 4), the formula R’ n SnX 4-n (where n = 1 or 2), or a mixture 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 represented by the formula MX’ v (where 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), the coating solution containing the hydrolyzable metal compound.

[0103] A coating solution comprising an organic solvent and a first organometallic compound represented by the formula RSnO (3 / 2-x / 2) (OH) x (where 0 < x < 3), wherein the solution contains about 0.0025 M to about 1.5 M of tin, and R is an alkyl group or cycloalkyl group having 3 to 31 carbon atoms, and the alkyl group or cycloalkyl group is bonded to tin at a secondary or tertiary carbon atom.

[0104] An inorganic pattern-forming precursor aqueous solution comprising a mixture of water, metal oxide cations, polyatomic inorganic anions, and a radiation-sensitive ligand containing peroxide groups.

[0105] Exposure is performed through a mask (reticle) to form a predetermined pattern, and for example, i-ray, KrF excimer laser, ArF excimer laser, EUV (extreme ultraviolet), or EB (electron beam) lasers are used. The resist underlayer forming composition of the present invention is preferably applied for EB (electron beam) or EUV (extreme ultraviolet) exposure, and more preferably for EUV (extreme ultraviolet) exposure. An alkaline developer is used for development, and the development temperature is appropriately selected from 5°C to 50°C and the development time from 10 seconds to 300 seconds. As the alkaline developer, for example, aqueous solutions of alkalis such as inorganic alkalis like sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia; primary amines like ethylamine and n-propylamine; secondary amines like diethylamine and di-n-butylamine; tertiary amines like triethylamine and methyldiethylamine; alcohol amines like dimethylethanolamine and triethanolamine; quaternary ammonium salts like tetramethylammonium hydroxide, tetraethylammonium hydroxide, and choline; and cyclic amines like pyrrole and piperidine can be used. Furthermore, appropriate amounts of alcohols such as isopropyl alcohol and nonionic surfactants can be added to the aqueous solutions of the above alkalis. Among these, preferred developers are aqueous solutions of quaternary ammonium salts, and more preferably aqueous solutions of tetramethylammonium hydroxide and choline. Furthermore, surfactants can also be added to these developers. Instead of an alkaline developer, a method can be used in which development is performed with an organic solvent such as butyl acetate to develop the parts of the photoresist where the alkali dissolution rate has not improved. Through the above process, a semiconductor substrate having a patterned resist film can be manufactured.

[0106] Next, the resist underlayer film is dry-etched using the formed resist pattern as a mask. At this time, if the inorganic film is formed on the surface of the semiconductor substrate used, the surface of the inorganic film is exposed; if the inorganic film is not formed on the surface of the semiconductor substrate used, the surface of the semiconductor substrate is exposed. After that, the semiconductor substrate is processed by a known method (such as dry etching) to manufacture a semiconductor device. [Examples]

[0107] The present invention will now be specifically described with reference to examples, but the present invention is not limited to these examples.

[0108] The weight-average molecular weight of the products shown in the synthesis examples of this specification was obtained by measurement using gel permeation chromatography (hereinafter abbreviated as GPC). A GPC instrument manufactured by Tosoh Corporation was used for the measurement, and the measurement conditions were as follows. • GPC columns: Shodex KF803L, Shodex KF802, Shodex KF801 [registered trademark] (Showa Denko K.K.) Column temperature: 40°C • Solvent: Tetrahydroxyfuran (THF) ·Flow rate: 1.0ml / min • Standard sample: Polystyrene (manufactured by Tosoh Corporation)

[0109] <Synthesis Example 1> 5.00 g of triglycidyl isocyanuric acid (manufactured by Nissan Chemical Corporation), 6.57 g of 3,3,3-trifluoropropionic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.19 g of tetrabutylphosphonium bromide (manufactured by ACROSS) were added to 17.65 g of propylene glycol monomethyl ether in a reaction vessel and dissolved. After purging the reaction vessel with nitrogen, the reaction was carried out at 105°C for 24 hours to obtain a solution. The solution did not become cloudy or otherwise discolored when cooled to room temperature, and its solubility in propylene glycol monomethyl ether was good. GPC analysis revealed that the product in the obtained solution had a weight-average molecular weight of 692 on a standard polystyrene basis and a dispersion degree of 1.31. The main compound obtained in this synthesis example is represented by the following formula (1a).

[0110] [ka]

[0111] <Synthesis Example 2> 5.00 g of triglycidyl isocyanuric acid (manufactured by Nissan Chemical Corporation), 10.9 g of 3-iodopropionic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.19 g of tetrabutylphosphonium bromide (manufactured by ACROSS) were added to 24.18 g of propylene glycol monomethyl ether in a reaction vessel and dissolved. After purging the reaction vessel with nitrogen, the reaction was carried out at 40°C for 48 hours to obtain a solution. The solution did not become cloudy or otherwise change when cooled to room temperature, and its solubility in propylene glycol monomethyl ether was good. GPC analysis revealed that the product in the obtained solution had a weight-average molecular weight of 901 on a standard polystyrene basis and a dispersion degree of 1.34. The main compound obtained in this synthesis example is represented by the following formula (2a). [ka]

[0112] <Synthesis Example 3> 7.00 g of 1,3,4,6-tetraglycidyl glycoluryl (manufactured by Shikoku Chemicals Co., Ltd.), 6.61 g of 3,3,3-trifluoropropionic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.08 g of tetrabutylphosphonium bromide (manufactured by ACROSS) were added to 8.89 g of propylene glycol monomethyl ether in a reaction vessel and dissolved. After purging the reaction vessel with nitrogen, the reaction was carried out at 105°C for 24 hours to obtain a solution. The solution did not become cloudy or otherwise change when cooled to room temperature, and its solubility in propylene glycol monomethyl ether was good. GPC analysis revealed that the product in the obtained solution had a weight-average molecular weight of 887 on a standard polystyrene basis and a dispersion degree of 1.24. The main compound obtained in this synthesis example is represented by the following formula (1b).

[0113] [ka]

[0114] <Synthesis Example 4> 8.00 g of 1,3,4,6-tetraglycidyl glycoluryl (manufactured by Shikoku Chemicals Co., Ltd.), 5.53 g of 3-iodopropionic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.08 g of tetrabutylphosphonium bromide (manufactured by ACROSS) were added to 6.69 g of propylene glycol monomethyl ether in a reaction vessel and dissolved. After purging the reaction vessel with nitrogen, the reaction was carried out at 105°C for 24 hours to obtain a solution. The solution did not become cloudy or otherwise change when cooled to room temperature, and its solubility in propylene glycol monomethyl ether was good. GPC analysis revealed that the product in the obtained solution had a weight-average molecular weight of 1197 on a standard polystyrene basis and a dispersion degree of 1.42. The main compound obtained in this synthesis example is represented by the following formula (2b).

[0115] [ka]

[0116] <Comparative Synthesis Example 1> 5.00 g of triglycidyl isocyanuric acid (manufactured by Nissan Chemical Corporation), 8.55 g of propionic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.19 g of tetrabutylphosphonium bromide (manufactured by ACROSS) were added to 24.18 g of propylene glycol monomethyl ether in a reaction vessel and dissolved. After purging the reaction vessel with nitrogen, the reaction was carried out at 105°C for 24 hours to obtain a solution. The solution did not become cloudy or otherwise change when cooled to room temperature, and its solubility in propylene glycol monomethyl ether was good. GPC analysis revealed that the product in the obtained solution had a weight-average molecular weight of 562 on a standard polystyrene basis and a dispersion degree of 1.21. The main compound obtained in this synthesis example is represented by the following formula (1c).

[0117] [ka]

[0118] <Comparative Synthesis Example 2> 8.00 g of 1,3,4,6-tetraglycidyl glycoluryl (manufactured by Shikoku Chemicals Co., Ltd.), 11.08 g of propionic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.19 g of tetrabutylphosphonium bromide (manufactured by ACROSS) were added to 24.18 g of propylene glycol monomethyl ether in a reaction vessel and dissolved. After purging the reaction vessel with nitrogen, the reaction was carried out at 105°C for 24 hours to obtain a solution. The solution did not become cloudy or otherwise change when cooled to room temperature, and its solubility in propylene glycol monomethyl ether was good. GPC analysis revealed that the product in the obtained solution had a weight-average molecular weight of 687 on a standard polystyrene basis and a dispersion degree of 1.21. The main compound obtained in this synthesis example is represented by the following formula (2c).

[0119] [ka]

[0120] <Example 1> To 4.25 g (solids content: 16.7% by weight) of the solution obtained in Synthesis Example 1 above, 0.25 g of tetramethoxymethyl glycoluryl (manufactured by Nippon Scitec Industries Co., Ltd.), 0.036 g of pyridinium phenolsulfonic acid, 175.53 g of propylene glycol monomethyl ether, and 19.92 g of propylene glycol monomethyl ether acetate were added and dissolved. The mixture was then filtered using a polyethylene microfilter with a pore size of 0.05 μm to obtain a lithography resist underlayer film forming composition.

[0121] <Example 2> To 9.24 g (solids content: 12.7% by weight) of the solution obtained in Synthesis Example 2 above, 0.41 g of tetramethoxymethyl glycoluryl (manufactured by Nippon Scitec Industries Co., Ltd.), 0.059 g of pyridinium phenolsulfonic acid, 0.26 g of propylene glycol monomethyl ether, and 29.83 g of propylene glycol monomethyl ether acetate were added and dissolved. The mixture was then filtered using a polyethylene microfilter with a pore size of 0.05 μm to obtain a lithography resist underlayer film forming composition.

[0122] <Example 3> To 7.18 g (solid content: 9.9 wt%) of the solution obtained in Synthesis Example 3 above, 0.25 g of tetramethoxymethyl glycoluryl (manufactured by Nippon Scitec Industries Co., Ltd.), 0.036 g of pyridinium phenolsulfonic acid, 172.63 g of propylene glycol monomethyl ether, and 19.90 g of propylene glycol monomethyl ether acetate were added and dissolved. The mixture was then filtered using a polyethylene microfilter with a pore size of 0.05 μm to obtain a lithography resist underlayer forming composition.

[0123] <Example 4> To 9.38 g (solid content: 9.1% by weight) of the solution obtained in Synthesis Example 4 above, 0.25 g of tetramethoxymethyl glycoluryl (manufactured by Nippon Scitec Industries Co., Ltd.), 0.036 g of pyridinium phenolsulfonic acid, 170.39 g of propylene glycol monomethyl ether, and 19.90 g of propylene glycol monomethyl ether acetate were added and dissolved. The mixture was then filtered using a polyethylene microfilter with a pore size of 0.05 μm to obtain a lithography resist underlayer film forming composition.

[0124] <Comparative Example 1> To 8.57 g (solids content: 10.0% by weight) of the solution obtained in Comparative Synthesis Example 1 described above, 0.25 g of tetramethoxymethyl glycoluryl (manufactured by Nippon Scitec Industries Co., Ltd.), 0.036 g of pyridinium phenolsulfonic acid, 171.39 g of propylene glycol monomethyl ether, and 19.90 g of propylene glycol monomethyl ether acetate were added and dissolved. The mixture was then filtered using a polyethylene microfilter with a pore size of 0.05 μm to obtain a lithography resist underlayer film forming composition.

[0125] <Comparative Example 2> To 8.57 g (solids content: 10.0 wt%) of the solution obtained in Comparative Synthesis Example 2 described above, 0.25 g of tetramethoxymethyl glycoluryl (manufactured by Nippon Scitec Industries Co., Ltd.), 0.036 g of pyridinium phenolsulfonic acid, 171.39 g of propylene glycol monomethyl ether, and 19.90 g of propylene glycol monomethyl ether acetate were added and dissolved. The mixture was then filtered using a polyethylene microfilter with a pore size of 0.05 μm to obtain a lithography resist underlayer forming composition.

[0126] [Elution test in photoresist solvent] The resist underlayer-forming compositions of Examples 1, 2, 3, 4, and Comparative Examples 1 and 2 were each applied onto a silicon wafer, which is a semiconductor substrate, using a spinner. The silicon wafer was then placed on a hot plate and baked at 205°C for 1 minute to form a resist underlayer (thickness 5 nm). These resist underlayers were immersed in a mixed solvent of ethyl lactate / propylene glycol monomethyl ether = 70 / 30 (mass ratio), which is used as a solvent for photoresists, and it was confirmed that they were insoluble in the solvent.

[0127] [Formation of positive resist patterns using an electron beam lithography system] The resist underlayer-forming compositions of Examples 1, 2, 3, 4, and Comparative Examples 1 and 2 were applied to silicon wafers using a spinner. The silicon wafers were baked on a hot plate at 205°C for 60 seconds to obtain a resist underlayer with a thickness of 5 nm. An EUV positive-type resist solution (containing methacrylic polymer) was spin-coated onto the resist underlayer and heated at 110°C for 60 seconds to form an EUV resist film. The resist film was exposed to electron beam lithography (ELS-G130) under predetermined conditions. After exposure, it was baked at 90°C for 60 seconds (PEB), cooled to room temperature on a cooling plate, developed with alkaline developer (2.38% TMAH), and then a resist pattern with 22 nm lines and 44 nm pitch was formed. A scanning electron microscope (Hitachi High-Technologies Corporation, CG4100) was used to measure the length of the resist pattern. In the formation of the resist pattern described above, a line pattern with a CD size of 22 nm was formed, which was indicated as "good," while any collapse or peeling of the line pattern was indicated as "bad."

[0128] [Table 1]

[0129] In Examples 1, 2, 3, and 4, the collapse and peeling of the line patterns were suppressed compared to Comparative Examples 1 and 2, suggesting that the pattern formation ability was excellent. [Industrial applicability]

[0130] The present invention is suitably applicable to a resist underlayer film composition for forming a resist underlayer film capable of forming a desired resist pattern, and to a method for manufacturing a semiconductor substrate with a resist pattern and a semiconductor device using the resist underlayer film forming composition.< / y> < / x>

Claims

1. A resist underlayer film forming composition comprising a compound represented by the following formula (1) and a solvent. 【Chemistry 1】 (In formula (1), X independently represents a halogen atom or a monovalent organic group having at least one halogen atom. Y represents an n-valent group, where n is an integer from 2 to 6. X does not have a benzene ring.)

2. The resist underlayer film forming composition according to claim 1, wherein X is represented by the following formula (2). 【Chemistry 2】 (In formula (2), X １ X represents a monovalent non-aromatic hydrocarbon group having at least one halogen atom. ２ is, -O-CO- ＊１ (*1 is X) １ This represents a bond between , -NR- (where R represents a monovalent organic group with 1 to 12 carbon atoms), or -S-. * represents a bond.

3. X １ The resist underlayer film forming composition according to claim 2, wherein the alkyl group has 1 to 12 carbon atoms and has at least one halogen atom.

4. The resist underlayer film forming composition according to claim 1, wherein the number of constituent atoms of Y is 5 to 30.

5. The resist underlayer forming composition according to claim 1, wherein Y comprises a carbon atom and at least one of a nitrogen atom and an oxygen atom.

6. The resist underlayer film forming composition according to claim 1, wherein Y is represented by the following formula (11) or (12). 【Transformation 3】 (In equations (11) and (12), * represents a coupling.)

7. The resist underlayer film forming composition according to claim 1, wherein the number of halogen atoms in X is 1 to 5.

8. The resist underlayer forming composition according to claim 1, wherein, in the compound represented by formula (1), when Y is the central part of the compound, at least one of the halogen atoms of X is located at the end of the compound.

9. The resist underlayer film forming composition according to claim 1, wherein the halogen atom is a fluorine atom or an iodine atom.

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

11. The resist underlayer film forming composition according to claim 1, further comprising an acid generator.

12. A resist underlayer film which is a fired product of a coated film made from the resist underlayer film forming composition according to any one of claims 1 to 11.

13. A step of forming a resist underlayer film by applying the resist underlayer film forming composition according to any one of claims 1 to 11 onto a semiconductor substrate and baking it, The process of applying a resist onto the resist underlayer film and baking it to form a resist film, A step of exposing the semiconductor substrate coated with the resist underlayer film and the resist film, The process involves developing the resist film after exposure and patterning the resist film, A method for manufacturing a semiconductor substrate having a patterned resist film, including the following.

14. A step of forming a resist underlayer film on a semiconductor substrate, comprising the resist underlayer film forming composition according to any one of claims 1 to 11, A step of forming a resist film on the resist underlayer film, A step of forming a resist pattern by irradiating the resist film with light or an electron beam and then developing it, A step of forming a patterned resist underlayer film by etching the resist underlayer film through the formed resist pattern, A process of processing a semiconductor substrate with the patterned resist underlayer film, A method for manufacturing a semiconductor device, including the method described above.

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