Resist underlayer film forming composition containing reaction products of hydantoin compounds

Abstract

The present invention provides: a composition for forming a resist underlayer film that enables the formation of a desired resist pattern; and a method for producing a resist pattern and a method for producing a semiconductor device, each of which uses the resist underlayer film-forming composition. The resist underlayer film-forming composition comprises an organic solvent and the reaction product of (A) a hydantoin-containing compound that has two epoxy groups and (B) a hydantoin-containing compound different from (A). This reaction product is preferably the reaction product of a secondary amino group present in the hydantoin-containing compound (B) and the epoxy group present in the hydantoin-containing compound (A).

Description

[Technical Field]

[0001] This invention relates to compositions used in lithography processes in semiconductor manufacturing, particularly in state-of-the-art lithography processes (ArF, EUV, EB, etc.). It also relates to a method for manufacturing a substrate with a resist pattern to which the resist underlayer film is applied, and a method for manufacturing a semiconductor device. [Background technology]

[0002] Conventionally, microfabrication using lithography with resist compositions has been performed in the manufacturing of semiconductor devices. This microfabrication method involves forming a thin film of a photoresist composition on a semiconductor substrate such as a silicon wafer, irradiating it with active light such as ultraviolet light through a mask pattern on which the device pattern is drawn, developing the film, and then etching the substrate using the resulting photoresist pattern as a protective film to form fine irregularities on the substrate surface corresponding to the pattern. In recent years, semiconductor devices have become more highly integrated, and in addition to the conventionally used i-line (wavelength 365nm), KrF excimer laser (wavelength 248nm), and ArF excimer laser (wavelength 193nm), the practical application of EUV light (extreme ultraviolet, wavelength 13.5nm) or EB (electron beam) is being considered for cutting-edge microfabrication. Consequently, the influence of the semiconductor substrate on the resist has become a major problem. Therefore, in order to solve this problem, a method of forming a resist underlayer film between the resist and the semiconductor substrate is being widely investigated.

[0003] Patent Document 1 discloses a resist underlayer forming composition containing a compound having a hydantoin ring. Patent Document 2 discloses a resist underlayer forming composition for EUV scopy containing a polymer obtained by condensing an isocyanuric acid-containing compound with barbital. Patent Document 3 discloses a resist underlayer forming composition for lithography having a structure containing a sulfonyl group at the polymer chain end. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] International Publication No. 2018 / 012253 [Patent Document 2] International Publication No. 2013 / 018802 [Patent Document 3] International Publication No. 2015 / 163195 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] The required properties for the resist underlayer include, for example, that it does not intermix with the resist film formed on top (i.e., it is insoluble in the resist solvent) and that it has a faster dry etching rate compared to the resist film.

[0006] In 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 and used with a thinner film thickness than conventional methods. When forming such thin films, pinholes and aggregation are likely to occur due to the influence of the substrate surface and the polymer used, making it difficult to form a uniform film without defects.

[0007] On the other hand, during the development process for forming a resist pattern, a method is sometimes employed in which the unexposed areas of the resist film are removed using a solvent capable of dissolving the resist film, usually an organic solvent, leaving the exposed areas as the resist pattern. In such negative development processes, improving the adhesion of the resist pattern is a major challenge.

[0008] Furthermore, there is a need to suppress the deterioration of LWR (Line Width Roughness, fluctuations in line width (roughness)) during resist pattern formation, to form a resist pattern with a good rectangular shape, and to improve resist sensitivity.

[0009] The present invention aims to provide a composition for forming a resist underlayer film that can form a desired resist pattern, and a resist pattern formation method using the resist underlayer film forming composition, which solves the above problems. [Means for solving the problem]

[0010] This invention encompasses the following:

[0011] [1] (A) A hydantoin-containing compound having two epoxy groups, (B) A hydantoin-containing compound different from (A) The reaction products, A resist underlayer film forming composition comprising an organic solvent.

[0012] [2] The resist underlayer film forming composition according to [1], wherein the reaction product is the reaction product of a secondary amino group of (B) a hydantoin-containing compound and an epoxy group of (A) a hydantoin-containing compound.

[0013] [3] Compound (A) above is formula (A-1), and compound (B) above is formula (B-1): [ka] [In equations (A-1) and (B-1), T 1 , T 2 , T 3 and T 4 Each of these independently represents an alkyl group having 1 to 10 carbon atoms, which may be interrupted by a hydrogen atom, an oxygen atom, or a sulfur atom, or which may be substituted with a hydroxyl group; an aryl group having 6 to 40 carbon atoms, which may be substituted with a hydroxyl group; or an alkenyl group having 3 to 6 carbon atoms. The resist underlayer film forming composition according to [1], each represented by ].

[0014] [4] The resist underlayer forming composition according to any one of [1] to [3], wherein the terminal end of the reaction product is sealed with a compound having a functional group.

[0015] [5] The resist lower layer film forming composition according to [4], wherein the functional group is selected from a carboxy group, a hydroxy group, an amino group, an imino group, and a thiol group.

[0016] [6] The resist lower layer film forming composition according to [4], wherein the compound having the functional group contains an aliphatic ring in which a carbon-carbon bond may be interrupted by a heteroatom and may be substituted with a substituent.

[0017] [7] The structure sealed with the compound having the functional group is represented by the following formulas (1) and (2): [Chemical formula] (In formulas (1) and (2), R1 represents an alkyl group having 1 to 6 carbon atoms, a phenyl group, a pyridyl group, a halogeno group, or a hydroxy group which may have a substituent, R2 represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a hydroxy group, a halogeno group, or an ester group represented by -C(=O)O-X, X represents an alkyl group having 1 to 6 carbon atoms which may have a substituent, R3 represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a hydroxy group, or a halogeno group, R4 represents a direct bond or a divalent organic group having 1 to 8 carbon atoms, R5 represents a divalent organic group having 1 to 8 carbon atoms, A represents an aromatic ring or an aromatic heterocyclic ring, t represents 0 or 1, and u represents 1 or 2.) The resist lower layer film forming composition according to [4] or [5].

[0018] [8] The resist lower layer film forming composition according to any one of [1] to [7], further comprising an acid generator.

[0019] [9] The resist lower layer film forming composition according to any one of [1] to [8], further comprising a crosslinking agent.

[0020]

[10] An electron beam or EUV resist lower layer film forming composition according to any one of [1] to [9].

[0021]

[11] A resist underlayer film characterized by being a fired product of a coated film made from any one of the resist underlayer film forming compositions described in [1] to

[10] .

[0022]

[12] A method for manufacturing a patterned substrate, comprising the steps of: applying a resist underlayer forming composition described in any one of [1] to

[10] onto a semiconductor substrate and baking it to form a resist underlayer; applying a resist onto the resist underlayer and baking it to form a resist film; exposing the semiconductor substrate covered with the resist underlayer and the resist; and developing and patterning the resist film after exposure.

[0023]

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

[10] , A step of forming a resist film on the resist underlayer film, A process of forming a resist pattern by irradiating a 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, characterized by including the following: [Effects of the Invention]

[0024] When forming a resist pattern using a resist underlayer film-forming composition containing the reaction product of (A) a hydantoin-containing compound having two epoxy groups and (B) a hydantoin-containing compound different from (A), the critical resolution size at which the resist pattern does not collapse after development becomes smaller compared to conventional resist underlayer films, enabling the formation of finer resist patterns. In addition, the range of resist pattern sizes that exhibit good patterns is increased compared to conventional techniques. [Modes for carrying out the invention]

[0025] The resist underlayer film forming composition of the present application contains (A) a hydantoin-containing compound having two epoxy groups, (B) a reaction product of a hydantoin-containing compound different from (A), and an organic solvent. It is preferable that the reaction product is a reaction product of the secondary amino group of the (B) hydantoin-containing compound and the epoxy group of the (A) hydantoin-containing compound. This reaction can be carried out by a known method. The above-mentioned (A) compound is of formula (A-1), and the (B) compound is of formula (B-1): [Chemical formula] [In formula (A-1) and formula (B-1), T 1 , T 2 , T 3 and T 4 each independently represents an alkyl group having 1 to 10 carbon atoms which may be interrupted by a hydrogen atom, an oxygen atom or a sulfur atom and may be substituted by a hydroxy group, an aryl group having 6 to 40 carbon atoms which may be substituted by a hydroxy group or an alkenyl group having 3 to 6 carbon atoms. It is preferably represented by each of the following. T 1 , T 2 , T 3 and T 4 may all be the same, may all be different, or some may be the same.

[0026] Among these, T 1 , T 2 , T 3 and T 4 are preferably an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 40 carbon atoms.

[0027] The alkyl groups having 1 to 10 carbon atoms include methyl group, ethyl group, n-propyl group, i-propyl group, cyclopropyl group, n-butyl group, i-butyl group, s-butyl group, t-butyl group, cyclobutyl group, 1-methyl-cyclopropyl group, 2-methyl-cyclopropyl group, n-pentyl group, 1-methyl-n-butyl group, 2-methyl-n-butyl group, 3-methyl-n-butyl group, 1,1-dimethyl-n-propyl group, 1,2-dimethyl-n-propyl group, 2,2-dimethyl-n-propyl group, and 1-ethyl-n-propyl group. Group, cyclopentyl group, 1-methyl-cyclobutyl group, 2-methyl-cyclobutyl group, 3-methyl-cyclobutyl group, 1,2-dimethyl-cyclopropyl group, 2,3-dimethyl-cyclopropyl group, 1-ethyl-cyclopropyl group, 2-ethyl-cyclopropyl group, n-hexyl group, 1-methyl-n-pentyl group, 2-methyl-n-pentyl group, 3-methyl-n-pentyl group, 4-methyl-n-pentyl group, 1,1-dimethyl-n-butyl group, 1,2-dimethyl-n-butyl group, 1,3-dimethyl-n-butyl group, 2,2 -dimethyl-n-butyl group, 2,3-dimethyl-n-butyl group, 3,3-dimethyl-n-butyl group, 1-ethyl-n-butyl group, 2-ethyl-n-butyl group, 1,1,2-trimethyl-n-propyl group, 1,2,2-trimethyl-n-propyl group, 1-ethyl-1-methyl-n-propyl group, 1-ethyl-2-methyl-n-propyl group, cyclohexyl group, 1-methyl-cyclopentyl group, 2-methyl-cyclopentyl group, 3-methyl-cyclopentyl group, 1-ethyl-cyclobutyl group, 2-ethyl-cyclobutyl group, 3-ethyl-cyclobutyl group, 1,2-dimethyl-cyclobutyl group, 1,3-dimethyl-cyclobutyl group, 2,2-dimethyl-cyclobutyl group, 2,3-dimethyl-cyclobutyl group, 2,4-dimethyl-cyclobutyl group, 3,3-dimethyl-cyclobutyl group, 1-n-propyl-cyclopropyl group, 2-n-propyl-cyclopropyl group, 1-i-propyl-cyclopropyl group, 2-i-propyl-cyclopropyl group, 1,2,2-trimethyl-cyclopropyl group, 1,2,3-trimethyl-cyclopropyl group, 2,2,Examples include 3-trimethylcyclopropyl group, 1-ethyl-2-methylcyclopropyl group, 2-ethyl-1-methylcyclopropyl group, 2-ethyl-2-methylcyclopropyl group, 2-ethyl-3-methylcyclopropyl group, and decyl group.

[0028] Examples of the above-mentioned aryl groups having 6 to 40 carbon atoms include phenyl group, o-methylphenyl group, m-methylphenyl group, p-methylphenyl group, o-chlorophenyl group, m-chlorophenyl group, p-chlorophenyl group, o-fluorophenyl group, p-fluorophenyl group, o-methoxyphenyl group, p-methoxyphenyl group, p-nitrophenyl group, p-cyanophenyl group, α-naphthyl group, β-naphthyl group, o-biphenylyl group, m-biphenylyl group, p-biphenylyl group, 1-anthryl group, 2-anthryl group, 9-anthryl group, 1-phenanthryl group, 2-phenanthryl group, 3-phenanthryl group, 4-phenanthryl group, and 9-phenanthryl group.

[0029] The above alkenyl groups having 3 to 6 carbon atoms include 1-propenyl group, 2-propenyl group, 1-methyl-1-ethenyl group, 1-butenyl group, 2-butenyl group, 3-butenyl group, 2-methyl-1-propenyl group, 2-methyl-2-propenyl group, 1-ethylethenyl group, 1-methyl-1-propenyl group, 1-methyl-2-propenyl group, 1-pentenyl group, 2-pentenyl group, 3-pentenyl group, 4-pentenyl group, 1-n-propylethenyl group, 1-methyl-1-butenyl group, 1-methyl-2-butenyl group, 1-methyl-3-butenyl group, and 2-ethyl-2 -Propenyl group, 2-methyl-1-butenyl group, 2-methyl-2-butenyl group, 2-methyl-3-butenyl group, 3-methyl-1-butenyl group, 3-methyl-2-butenyl group, 3-methyl-3-butenyl group, 1,1-dimethyl-2-propenyl group, 1-i-propylethenyl group, 1,2-dimethyl-1-propenyl group, 1,2-dimethyl-2-propenyl group, 1-cyclopentenyl group, 2-cyclopentenyl group, 3-cyclopentenyl group, 1-hexenyl group, 2-hexenyl group, 3-hexenyl group, 4-hexenyl group, 5-hexenyl group, 1-methyl-1 -Pentenyl group, 1-methyl-2-pentenyl group, 1-methyl-3-pentenyl group, 1-methyl-4-pentenyl group, 1-n-butylethenyl group, 2-methyl-1-pentenyl group, 2-methyl-2-pentenyl group, 2-methyl-3-pentenyl group, 2-methyl-4-pentenyl group, 2-n-propyl-2-propenyl group, 3-methyl-1-pentenyl group, 3-methyl-2-pentenyl group, 3-methyl-3-pentenyl group, 3-methyl-4-pentenyl group, 3-ethyl-3-butenyl group, 4-methyl-1-pentenyl group, 4-methyl-2-pentenyl group, 4-methyl-3-pentenyl group, 4-methyl-4-pentenyl group, 1,1-dimethyl-2-butenyl group, 1,1-dimethyl-3-butenyl group, 1,2-dimethyl-1-butenyl group, 1,2-dimethyl-2-butenyl group, 1,2-dimethyl-3-butenyl group, 1-methyl-2-ethyl-2-propenyl group, 1-s-butylethenyl group, 1,3-dimethyl-1-butenyl group, 1,3-dimethyl-2-butenyl group, 1,3-dimethyl-3-butenyl group, 1-i-butylethenyl group, 2,2-dimethyl-3-butenyl group, 2,3-dimethyl-1-butenyl group, 2,3-dimethyl-2-butenyl group, 2,3-dimethyl-3-butenyl group, 2-i-propyl-2-propenyl group, 3,3-dimethyl-1-butenyl group, 1-ethyl-1-butenyl group, 1-ethyl-2-butenyl group, 1-ethyl-3-butenyl group, 1-n-propyl-1-propenyl group, 1-n-propyl-2-propenyl group, 2-ethyl-1-butenyl group, 2-ethyl-2-butenyl group, 2-ethyl-3-butenyl group, 1,1,2-trimethyl-2-propenyl group, 1-t-butylethenyl group, 1-methyl-1-ethyl-2-propenyl group, 1-ethyl-2-methyl-1-propenyl group, 1-ethyl-2-methyl-2-propenyl group, 1-i-propyl-1-propenyl group, 1-i- Examples include propyl-2-propenyl group, 1-methyl-2-cyclopentenyl group, 1-methyl-3-cyclopentenyl group, 2-methyl-1-cyclopentenyl group, 2-methyl-2-cyclopentenyl group, 2-methyl-3-cyclopentenyl group, 2-methyl-4-cyclopentenyl group, 2-methyl-5-cyclopentenyl group, 2-methylene-cyclopentyl group, 3-methyl-1-cyclopentenyl group, 3-methyl-2-cyclopentenyl group, 3-methyl-3-cyclopentenyl group, 3-methyl-4-cyclopentenyl group, 3-methyl-5-cyclopentenyl group, 3-methylene-cyclopentyl group, 1-cyclohexenyl group, 2-cyclohexenyl group, and 3-cyclohexenyl group.

[0030] The following compounds are examples of preferred specific examples of the above (A) compound.

[0031] [ka] The following compounds are examples of preferred specific examples of the above (B) compound.

[0032] [ka] Examples of organic solvents included in the resist underlayer film forming composition of the present invention include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, propylene glycol propyl ether acetate, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, and cyclopentanopropyl ether. Examples of solvents include cyclohexanone, cycloheptanone, 4-methyl-2-pentanol, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate, ethyl ethoxyacetate, 2-hydroxyethyl acetate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, 2-heptanone, methoxycyclopentane, anisole, γ-butyrolactone, N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide. These solvents can be used individually or in combination of two or more.

[0033] 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.

[0034] The weight-average molecular weight of the above reaction product is preferably 500 to 50,000, more preferably 1,000 to 30,000. The weight-average molecular weight can be measured, for example, by the gel permeation chromatography method described in the examples.

[0035] It is preferable that the terminal end of the reaction product is sealed with a compound having a functional group.

[0036] It is preferable that the functional group is selected from a carboxyl group, a hydroxyl group, an amino group, an imino group, and a thiol group.

[0037] It is preferable that the compound having the functional group includes an aliphatic ring in which the carbon-carbon bond may be interrupted by a heteroatom and may be substituted with a substituent.

[0038] The aliphatic ring is preferably a monocyclic or polycyclic aliphatic ring having 3 to 10 carbon atoms.

[0039] The polycyclic aliphatic ring is preferably a bicyclo ring or a tricyclo ring.

[0040] It is preferable that the aliphatic ring has at least one unsaturated bond.

[0041] The description of carboxyl group-containing compounds including an aliphatic ring in which the carbon-carbon bond may be interrupted by a heteroatom and may be substituted with a substituent is in accordance with the content described in PCT / JP2020 / 018436.

[0042] A structure in which the terminal end of the reaction product of compound (A) and compound (B) is sealed with an aliphatic ring in which the carbon-carbon bond may be interrupted by a heteroatom and may be substituted with a substituent can be produced by reacting the reaction product of compound (A) and compound (B) with a carboxyl group-containing compound that includes an aliphatic ring in which the carbon-carbon bond may be interrupted by a heteroatom and may be substituted with a substituent, as described below.

[0043] Specific examples of carboxyl group-containing compounds that include an aliphatic ring in which the carbon-carbon bond may be interrupted by a heteroatom and may be substituted with a substituent include the compounds listed below. Compounds in which the carboxyl group of the following specific examples is replaced with a hydroxyl group, an amino group, and a thiol group are also examples.

[0044] [ka] [ka] [ka] The structure sealed with the compound having the aforementioned functional group is defined by the following formula (1) or formula (2): [ka] (In formulas (1) and (2), R1 represents an optionally substituted alkyl group having 1 to 6 carbon atoms, a phenyl group, a pyridyl group, a halogen group, or a hydroxyl group; R2 represents a hydrogen atom, an optionally substituted alkyl group having 1 to 6 carbon atoms, a hydroxyl group, a halogen group, or an ester group represented by -C(=O)OX; X represents an optionally substituted alkyl group having 1 to 6 carbon atoms; R3 represents a hydrogen atom, an optionally substituted alkyl group having 1 to 6 carbon atoms, a hydroxyl group, or a halogen group; R4 represents a direct bond or a divalent organic group having 1 to 8 carbon atoms; R5 represents a divalent organic group having 1 to 8 carbon atoms; A represents an aromatic ring or an aromatic heterocycle; t represents 0 or 1; and u represents 1 or 2.)

[0045] The explanations of the terms used in formulas (1) and (2) above shall be in accordance with those specified in WO2015 / 163195.

[0046] The terminal structures of the reaction product of compound (A) and compound (B), represented by formulas (1) and (2) above, can be produced by the reaction of the reaction product of compound (A) and compound (B) with the compound represented by the following formula (1a) and / or the compound represented by the following formula (2a).

[0047] [ka] (The meanings of the symbols in equations (1a) and (2a) above are as explained in equations (1) and (2) above.) Examples of compounds represented by formula (1a) include those represented by the following formula. Compounds in which the carboxyl group or hydroxyl group in the following specific examples are replaced with an amino group or thiol group are also examples.

[0048] [ka] [ka] [ka] [ka] [ka] Examples of compounds represented by formula (2a) include those represented by the following formula. Compounds in which the carboxyl group in the following specific example is replaced with a hydroxyl group, an amino group, or a thiol group are also examples.

[0049] [ka] Furthermore, the following compounds are examples of compounds containing the imino group.

[0050] [ka]

[0051] <Acid Generator> As an optional component in the resist underlayer film forming composition of the present invention, either a thermal acid generator or a photoacid generator can be used, but the use of a thermal acid generator is preferred. Examples of thermal acid generators include sulfonic acid compounds and carboxylic acid compounds such as p-toluenesulfonic acid, trifluoromethanesulfonic acid, pyridinium-p-toluenesulfonate (pyridinium-p-toluenesulfonic 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. Examples of the photoacid generators include onium salt compounds, sulfonimide compounds, and disulfonyldiazomethane compounds. Examples of iodonium salt compounds include iodonium salt compounds such as diphenyliodonium hexafluorophosphate, diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoron-butanesulfonate, diphenyliodonium perfluoron-octanesulfonate, diphenyliodonium camphorsulfonate, bis(4-tert-butylphenyl)iodonium camphorsulfonate and bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate, as well as sulfonium salt compounds such as triphenylsulfonium hexafluoroantimonate, triphenylsulfonium nonafluoron-butanesulfonate, triphenylsulfonium camphorsulfonate and triphenylsulfonium trifluoromethanesulfonate. Examples of sulfonimide compounds include N-(trifluoromethanesulfonyloxy)succinimide, N-(nonafluoron-butanesulfonyloxy)succinimide, N-(camphorsulfonyloxy)succinimide, and N-(trifluoromethanesulfonyloxy)naphthalimide. 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. The aforementioned acid generating agent can be used by one type only, or by a combination of two or more types. When the above-mentioned 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 described below.

[0052] <Crosslinking agent> Examples of crosslinking agents that may be included as optional components in the resist underlayer film forming composition of the present invention 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, 1,1,3,3-tetrakis(methoxymethyl)urea, and 2,4,6-tris[bis(methoxymethyl)amino]-1,3,5-triazine ((trade name) Cymel®-303, Nikalac® MW-390). Furthermore, the crosslinking agent of this application may be a nitrogen-containing compound having 2 to 6 substituents represented by the following formula (1X) that bond to a nitrogen atom in one molecule, as described in WO2017 / 187969. [ka] (In formula (1X), R1 represents a methyl group or an ethyl group.) A nitrogen-containing compound having 2 to 6 substituents represented by the above formula (1X) in one molecule may be a glycoluryl derivative represented by the following formula (1A). [ka] (In formula (1A), 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.) Examples of glycoluryl derivatives represented by formula (1A) include the compounds represented by the following formulas (1A-1) to (1A-6). [ka] The compound represented by formula (1A) is obtained by reacting a nitrogen-containing compound having 2 to 6 substituents represented by formula (2X) in one molecule that bond to a nitrogen atom with at least one compound represented by formula (3) below to produce a nitrogen-containing compound having 2 to 6 substituents represented by formula (1X) in one molecule. [ka] (In formulas (2X) and (3), R1 represents a methyl group or an ethyl group, and R4 represents an alkyl group having 1 to 4 carbon atoms.) The glycoluryl derivative represented by formula (1A) is obtained by reacting the glycoluryl derivative represented by formula (2A) with at least one compound represented by formula (3). A nitrogen-containing compound having 2 to 6 substituents represented by the above formula (2X) in one molecule is, for example, a glycoluryl derivative represented by the following formula (2A). [ka] (In formula (2A), 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.) Examples of glycoluryl derivatives represented by formula (2A) include the compounds represented by formulas (2A-1) to (2A-4) below. Furthermore, examples of compounds represented by formula (3) include the compounds represented by formulas (3-1) and (3-2) below. [ka] [ka] With regard to nitrogen-containing compounds having 2 to 6 substituents represented by the following formula (1X) bonded to the above-mentioned nitrogen atom in one molecule, the contents described in Publication WO2017 / 187969 shall be as described. When the above-mentioned 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 reaction product.

[0053] <Other ingredients> The resist underlayer film-forming composition of the present invention does not produce pinholes or striations, and a surfactant 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 typically 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 of the present invention. These surfactants may be added individually or in combination of two or more types.

[0054] The resist underlayer forming composition of the present invention is preferably an electron beam resist underlayer forming composition or an EUV resist underlayer forming composition used in an electron beam (EB) lithography process and an EUV exposure process, and is preferably an EUV resist underlayer forming composition.

[0055] <Underlying resist film> The resist underlayer film according to the present invention can be manufactured by applying the above-described resist underlayer film forming composition onto a semiconductor substrate and firing it.

[0056] The resist underlayer film according to the present invention is preferably an electron beam resist underlayer film or an EUV resist underlayer film.

[0057] 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.

[0058] 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.

[0059] The resist underlayer film forming composition of the present invention is applied to such a semiconductor substrate by an appropriate coating method such as a spinner or coater. Then, the resist underlayer film is formed by baking using a heating means such as a hot plate. The baking conditions are appropriately selected from a 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, more preferably, the bake temperature is 150°C to 300°C and the bake time is 0.8 minutes to 10 minutes. 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.

[0060] 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 (1 nm). The thicknesses are as follows: 0.004μm(4nm)~0.05μm(50nm), 0.005μm(5nm)~0.05μm(50nm), 0.003μm(3nm)~0.03μm(30nm), 0.003μm(3nm)~0.02μm(20nm), and 0.005μm(5nm)~0.02μm(20nm).

[0061] <Manufacturing method for patterned substrates, manufacturing method for semiconductor devices> The manufacturing process for patterned substrates involves the following steps. Typically, a photoresist layer is formed 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 (manufactured by JSR Corporation), APEX-E (manufactured by Cyprey Corporation), PAR710 (manufactured by Sumitomo Chemical Co., Ltd.), and AR2772 and SEPR430 (manufactured by 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).

[0062] 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, but the resist underlayer forming composition of this application is preferably applied for EUV (extreme ultraviolet) or EB (electron beam) exposure, and is particularly preferably applied 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 quaternary ammonium salts, and more preferably 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 substrate with the resist patterned can be manufactured.

[0063] 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 substrate is processed by a known method (such as dry etching) to manufacture a semiconductor device. [Examples]

[0064] The present invention will be described more specifically below with reference to examples and comparative examples, but the present invention is not limited to the following examples.

[0065] The weight-average molecular weight (Mw) of polymer (A) shown in the synthesis example below was measured using gel permeation chromatography (GPC). A GPC instrument manufactured by Tosoh Corporation was used for the measurement, and the measurement conditions were as follows.

[0066] Measuring device: HLC-8020GPC [product name] (manufactured by Tosoh Corporation) GPC columns: TSKgel G2000HXL; 2 tubes, G3000HXL; 1 tube, G4000HXL; 1 tube [product name] (all manufactured by Tosoh Corporation) Column temperature: 40℃ Solvent: Tetrahydrofuran (THF) Flow rate: 1.0ml / min Standard sample: Polystyrene (manufactured by Tosoh Corporation)

[0067] [Synthesis Example 1] Synthesis of reaction product 1 4.91 g of N,N-diglycidyl-5,5-dimethylhydantoin, 2.83 g of 5,5-dimethylhydantoin, and 0.27 g of tetrabutylphosphonium bromide were dissolved in 12.00 g of propylene glycol monomethyl ether. After purging the reaction vessel with nitrogen, the reaction was carried out under reflux heating for 24 hours to obtain a solution of reaction product 1. GPC analysis revealed that the weight-average molecular weight of reaction product 1 in the obtained solution was 1400 on a standard polystyrene basis.

[0068] Reaction product 1 contains the following structure as a repeating unit structure.

[0069] [ka]

[0070] [Synthesis Example 2] Synthesis of Reaction Product 2 4.00 g of N,N-diglycidyl-5,5-dimethylhydantoin, 3.71 g of 5-phenylhydantoin, and 0.30 g of tetrabutylphosphonium bromide were dissolved in 12.00 g of propylene glycol monomethyl ether. After purging the reaction vessel with nitrogen, the reaction was carried out under reflux heating for 24 hours to obtain a solution of reaction product 2. GPC analysis revealed that the weight-average molecular weight of reaction product 2 in the obtained solution was 3500 on a standard polystyrene basis.

[0071] Reaction product 2 contains the following structure as a repeating unit structure.

[0072] [ka]

[0073] [Synthesis Example 3] Synthesis of Reaction Product 3 3.66 g of N,N-diglycidyl-5,5-dimethylhydantoin, 4.15 g of 5,5-diphenylhydantoin, and 0.20 g of tetrabutylphosphonium bromide were dissolved in 12.00 g of propylene glycol monomethyl ether. After purging the reaction vessel with nitrogen, the reaction was carried out under reflux heating for 24 hours to obtain a solution of reaction product 3. GPC analysis revealed that the weight-average molecular weight of reaction product 3 in the obtained solution was 3100 on a standard polystyrene basis.

[0074] Reaction product 3 contains the following structure as a repeating unit structure.

[0075] [ka]

[0076] [Synthesis Example 4] Synthesis of Reaction Product 4 4.52 g of N,N-diglycidyl-5,5-dimethylhydantoin, 2.97 g of 5-phenylhydantoin, 1.17 g of 3-hydroxy-1-adamantanecarboxylic acid, and 0.34 g of tetrabutylphosphonium bromide were dissolved in 11.00 g of propylene glycol monomethyl ether. After purging the reaction vessel with nitrogen, the reaction was carried out under reflux heating for 24 hours to obtain a solution of reaction product 4. GPC analysis revealed that the weight-average molecular weight of reaction product 4 in the obtained solution was 2400 on a standard polystyrene basis.

[0077] Reaction product 4 contains the following structure as a repeating unit structure.

[0078] [ka]

[0079] [Synthesis Example 5] Synthesis of Reaction Product 5 4.01 g of N,N-diglycidyl-5,5-dimethylhydantoin, 2.64 g of 5-phenylhydantoin, 1.06 g of 4-(methylsulfonyl)benzoic acid, and 0.30 g of tetrabutylphosphonium bromide were dissolved in 12.00 g of propylene glycol monomethyl ether. After purging the reaction vessel with nitrogen, the reaction was carried out under reflux heating for 24 hours to obtain a solution of reaction product 5. GPC analysis revealed that the weight-average molecular weight of reaction product 5 in the obtained solution was 1900 on a standard polystyrene basis.

[0080] Reaction product 5 contains the following structure as a repeating unit structure.

[0081] [ka]

[0082] [Synthesis Example 6] Synthesis of Reaction Product 6 4.62 g of N,N-diglycidyl-5,5-dimethylhydantoin, 3.04 g of 5-phenylhydantoin, 1.06 g of 5-norbornene-2,3-dicarboxylic acid anhydride, and 0.34 g of tetrabutylphosphonium bromide were dissolved in 11.00 g of propylene glycol monomethyl ether. After purging the reaction vessel with nitrogen, the reaction was carried out under reflux heating for 24 hours to obtain a solution of reaction product 6. GPC analysis revealed that the weight-average molecular weight of reaction product 6 in the obtained solution was 2100 on a standard polystyrene basis.

[0083] Reaction product 6 contains the following structure as a repeating unit structure.

[0084] [ka]

[0085] <Comparative Synthesis Example 1> 8.00 g of monoallyl diglycidyl isocyanuric acid, 5.45 g of barbital, and 0.48 g of tetrabutylphosphonium bromide were dissolved in 56.00 g of propylene glycol monomethyl ether. After purging the reaction vessel with nitrogen, the reaction was carried out under reflux heating for 10 hours to obtain a solution of reaction product 7. GPC analysis revealed that the weight-average molecular weight of reaction product 7 in the obtained solution was 10,000 on a standard polystyrene basis.

[0086] Reaction product 7 contains the following structure as a repeating unit structure.

[0087] [ka]

[0088] <Comparative Synthesis Example 2> 3.66 g of N,N-diglycidyl-5,5-dimethylhydantoin, 5.45 g of barbital, and 0.48 g of tetrabutylphosphonium bromide were dissolved in 56.00 g of propylene glycol monomethyl ether. After purging the reaction vessel with nitrogen, the reaction was carried out under reflux heating for 10 hours to obtain a solution of reaction product 8. GPC analysis revealed that the weight-average molecular weight of reaction product 8 in the obtained solution was 4000 on a standard polystyrene basis.

[0089] Reaction product 8 contains the following structure as a repeating unit structure.

[0090] [ka]

[0091] [Example 1] To 3.12 g of the solution containing 0.047 g of reaction product 1 obtained in Synthesis Example 1 above, 0.11 g of tetramethoxymethyl glycoluryl and 0.012 g of pyridinium p-phenolsulfonate salt were mixed, and 263.41 g of propylene glycol monomethyl ether and 29.89 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 prepare a resist underlayer film forming composition.

[0092] [Examples 2-6] A resist underlayer film forming composition was prepared in the same manner as in Example 1, except that reaction products 2 to 6 were used instead of reaction product 1.

[0093] [Comparative Examples 1-2] A resist underlayer film forming composition was prepared in the same manner as in Example 1, except that reaction products 7-8 were used instead of reaction product 1.

[0094] (Resistance patterning evaluation) [Test of resist pattern formation using electron beam lithography equipment] A resist underlayer-forming composition was applied to a silicon wafer using a spinner. The silicon wafer was baked on a hot plate at 205°C for 60 seconds to obtain a resist underlayer with a thickness of 5 nm. An EUV negative-type resist solution (containing methacrylic polymer) was spin-coated onto the resist underlayer and heated at 100°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 (PEB) at 100°C for 60 seconds, cooled to room temperature on a cooling plate, developed with butyl acetate, and then a resist pattern with pillar sizes of 17 nm to 28 nm was formed. A scanning electron microscope (Hitachi High-Technologies Corporation, CG4100) was used to measure the length of the resist pattern.

[0095] The photoresist patterns obtained in this way were observed from above to determine the smallest CD size within a shot where no collapse was observed in the resist pattern, and the largest CD size where no connection (bridging) to adjacent patterns was observed, thereby confirming the range in which the pattern was well resolved. A larger range indicates a wider range in which a good pattern can be formed. The results of Examples 1 to 6 show that the size range in which a good pattern can be formed is wider compared to Comparative Examples 1 and 2.

[0096] Table 1 shows the observation results of the resist patterns confirmed in Examples 1-6 and Comparative Examples 1 and 2 described above.

[0097] [Table 1] [Industrial applicability]

[0098] The resist underlayer film forming composition according to the present invention provides a composition for forming a resist underlayer film capable of forming a desired resist pattern, a method for manufacturing a substrate with a resist pattern using the resist underlayer film forming composition, and a method for manufacturing a semiconductor device.

Claims

1. (A) A hydantoin-containing compound having two epoxy groups, (B) A hydantoin-containing compound different from (A) The reaction product, the repeating unit structure of which consists only of the reaction product of the reaction between the secondary amino group of the hydantoin-containing compound (B) and the epoxy group of the hydantoin-containing compound (A), and an organic solvent, wherein compound (A) is of formula (A-1) and compound (B) is of formula (B-1): 【Transformation 33】 [In formulas (A-1) and (B-1), T １ , T ２ , T ３ and T ４ Each of these independently represents an alkyl group having 1 to 10 carbon atoms, which may be interrupted by a hydrogen atom, an oxygen atom, or a sulfur atom, or which may be substituted with a hydroxyl group; an aryl group having 6 to 40 carbon atoms, which may be substituted with a hydroxyl group; or an alkenyl group having 3 to 6 carbon atoms. A resist underlayer film forming composition represented by each of these.

2. The resist underlayer film forming composition according to claim 1, wherein the terminal end of the reaction product is sealed with a compound having a functional group.

3. The resist underlayer film forming composition according to claim 2, wherein the functional group is selected from a carboxyl group, a hydroxyl group, an amino group, an imino group, and a thiol group.

4. The resist underlayer forming composition according to claim 2, wherein the compound having the functional group comprises an aliphatic ring in which the carbon-carbon bond may be interrupted by a heteroatom and may be substituted with a substituent.

5. The structure encapsulated with the compound having the functional group is defined by the following formulas (1) and (2): 【Transformation 34】 A resist underlayer forming composition according to claim 2 or 3, represented by formula (1) and formula (2), where R1 represents an optionally substituted alkyl group having 1 to 6 carbon atoms, a phenyl group, a pyridyl group, a halogeno group, or a hydroxyl group; R2 represents a hydrogen atom, an optionally substituted alkyl group having 1 to 6 carbon atoms, a hydroxyl group, a halogeno group, or an ester group represented by -C(=O)O-X; X represents an optionally substituted alkyl group having 1 to 6 carbon atoms; R3 represents a hydrogen atom, an optionally substituted alkyl group having 1 to 6 carbon atoms, a hydroxyl group, or a halogeno group; R4 represents a direct bond or a divalent organic group having 1 to 8 carbon atoms; R5 represents a divalent organic group having 1 to 8 carbon atoms; A represents an aromatic ring or an aromatic heterocycle; t represents 0 or 1; and u represents 1 or 2.

6. The resist underlayer film forming composition according to any one of claims 1 to 5, further comprising an acid generator.

7. The resist underlayer film forming composition according to any one of claims 1 to 6, further comprising a crosslinking agent.

8. The resist underlayer forming composition according to any one of claims 1 to 7, wherein the resist underlayer forming composition is an electron beam or EUV resist underlayer forming composition.

9. A resist underlayer film characterized by being a fired product of a coated film made from the resist underlayer film forming composition according to any one of Claims 1 to 8.

10. A method for manufacturing a patterned substrate, comprising the steps of: applying a resist underlayer film forming composition according to any one of claims 1 to 8 onto a semiconductor substrate and baking it to form a resist underlayer film; applying a resist onto the resist underlayer film and baking it to form a resist film; exposing the semiconductor substrate covered with the resist underlayer film and the resist; and developing and patterning the resist film after exposure.

11. A step of forming a resist underlayer on a semiconductor substrate, comprising the resist underlayer forming composition according to any one of claims 1 to 8, A step of forming a resist film on the resist underlayer film, A process of forming a resist pattern by irradiating a 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, characterized by including the following:

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