Composition for forming resist underlayer film

Abstract

A composition for forming a resist underlayer film, which contains a compound (A) containing an aromatic hydrocarbon ring to which a phenolic hydroxyl group is bonded, and a solvent (B), and which is characterized in that the atomic percentage of oxygen in the phenolic hydroxyl group in a cured film of the composition is 2.00% or more.

Description

Technical Field

[0001] This invention relates to compositions for forming a photoresist underlayer, photoresist underlayers, laminates, methods for manufacturing semiconductor devices, and methods for patterning. Background Technology

[0002] In the manufacture of semiconductor devices, photolithography using photoresist compositions has long been used for microfabrication. This microfabrication involves forming a thin film of photoresist composition on a semiconductor substrate such as a silicon wafer, irradiating it with active light such as ultraviolet light through a mask pattern depicting the device, developing the film, and then using the resulting photoresist pattern as a protective film to etch the substrate, thereby forming a micro-unfolding pattern corresponding to the photoresist pattern on the substrate surface. In recent years, with the increasing integration of semiconductor devices, in addition to the commonly used i-rays (wavelength 365nm), KrF excimer lasers (wavelength 248nm), and ArF excimer lasers (wavelength 193nm), the practical application of EUV light (wavelength 13.5nm) or EB (electron beam) has been studied for the most advanced microfabrication. Along with this, poor photoresist pattern formation caused by influences from the semiconductor substrate has become a major problem. Therefore, to solve this problem, methods of setting a photoresist underlayer film between the photoresist and the semiconductor substrate have been extensively researched.

[0003] Patent Document 1 discloses a composition for forming a photolithographic underlayer film comprising a naphthalene ring having halogen atoms. Patent Document 2 discloses a halogenated antireflective film. Patent Document 3 discloses a composition for forming a resist underlayer film.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: International Publication No. 2006 / 003850

[0007] Patent Document 2: Japanese Patent Publication No. 2005-526270

[0008] Patent Document 3: International Publication No. 2020 / 111068 Summary of the Invention

[0009] The problem that the invention aims to solve

[0010] As required properties of the underlying resist film, examples include not mixing with the resist film formed on the upper layer (insoluble in resist solvent) and being able to form resist patterns with high sensitivity.

[0011] The present invention was made in view of the above circumstances, and its object is to provide a composition for forming a photoresist underlayer film capable of forming a photoresist underlayer film with high sensitivity, and a method for manufacturing a photoresist underlayer film, a stack, a semiconductor device, and a patterning method using the composition for forming a photoresist underlayer film.

[0012] Methods for solving problems

[0013] In order to solve the above-mentioned problems, the inventors conducted in-depth research and found that the above-mentioned problems could be solved, and completed the present invention with the following essential points.

[0014] That is, the present invention includes the following solutions.

[0015] [1] A composition for forming a resist underlayer film, comprising a compound (A) and a solvent (B), wherein the compound (A) contains an aromatic hydrocarbon ring bound with a phenolic hydroxyl group. The atomic percentage of oxygen in the phenolic hydroxyl groups of the cured film of the above composition is 2.00% or more.

[0016] [2] According to the composition for forming a resist underlayer film as described in [1], the compound (A) contains at least one of phenol resin, naphthol resin, biphenol resin, polyhydroxystyrene and polyhydroxyvinylnaphthalene.

[0017] [3] According to the composition for forming a resist underlayer film as described in [1], the above compound (A) is a low molecular weight compound (A-1) containing two or more phenolic hydroxyl groups and having a molecular weight of 5,000 or less.

[0018] [4] The composition for forming a resist underlayer film according to any one of [1] to [3] further comprises a crosslinking agent (C).

[0019] [5] The composition for forming a resist underlayer film according to any one of [1] to [4] is a composition for forming a resist underlayer film for EUV or electron beam lithography.

[0020] [6] A resist underlayer film, which is a cured product of the resist underlayer film forming composition described in any one of [1] to [5].

[0021] [7] According to the resist underlayer film described in [6], the atomic percentage of oxygen in the phenolic hydroxyl group in the resist underlayer film is 2.00% or more.

[0022] [8] The resist underlayer film according to [6] or [7] has a thickness of 2 nm or more and 20 nm or less.

[0023] [9] A laminated body comprising: Semiconductor substrates, and The resist underlayer film as described in any one of [6] to [8].

[0024]

[10] A method for manufacturing a semiconductor device, comprising the following steps: The process of forming a photoresist underlayer film on a semiconductor substrate using any one of [1] to [5]; and The process of forming a resist film on the lower resist film mentioned above.

[0025]

[11] A pattern forming method, comprising the following steps: The process of forming a photoresist underlayer film on a semiconductor substrate using the composition for forming a photoresist underlayer film as described in any one of [1] to [5]; The process of forming a resist film on the aforementioned lower resist film; The process of irradiating the above-mentioned resist film with light or an electron beam, and then developing the above-mentioned resist film to obtain a resist pattern; and The process of using the above-mentioned resist pattern as a mask to etch the above-mentioned resist underlayer film.

[0026] The effects of the invention

[0027] According to the present invention, a composition for forming a photoresist underlayer film capable of forming a photoresist underlayer film with high sensitivity can be provided, as well as a method for manufacturing a photoresist underlayer film, a stack, a semiconductor element, and a patterning method using the composition for forming a photoresist underlayer film. Detailed Implementation

[0028] (Composition for forming the lower layer of the resist film)

[0029] The composition for forming a resist underlayer film of the present invention comprises a compound (A) containing an aromatic hydrocarbon ring with a phenolic hydroxyl group and a solvent (B).

[0030] The composition for forming the lower layer film of the resist may also contain a crosslinking agent (C), a curing catalyst (D), etc.

[0031] The atomic percentage of oxygen in the phenolic hydroxyl groups of the cured film of the composition is 2.00% or more, preferably 2.00% or more and 30.00% or less, more preferably 3.00% or more and 20.00% or less. Because the atomic percentage of oxygen in the phenolic hydroxyl groups of the cured film of the composition is 2.00% or more, a resist underlayer film capable of forming resist patterns with high sensitivity can be formed.

[0032] The atomic percentage of oxygen in the phenolic hydroxyl groups of the cured film of the composition can be determined, for example, by the following method.

[0033] The resist underlayer film formation composition was coated onto a silicon wafer using a spin coater. The silicon wafer was then baked on a hot plate at 205°C for 60 seconds to obtain a resist underlayer film with a thickness of 5 nm. The silicon wafer with the resist underlayer film was cut into pieces approximately 0.5 × 1 cm in size and dried under reduced pressure for more than 20 hours. Then, it was sealed in a 6.0 × 7.5 cm weighing bottle with 3 ml of trifluoroacetic anhydride, and the hydrogen atoms of the phenolic hydroxyl groups were replaced with trifluoroacetyl groups by gas-phase chemical modification at 25°C. The reaction time was set according to the time required for each composition to reach reaction equilibrium. Unreacted trifluoroacetic anhydride and trifluoroacetic acid generated as a byproduct were further removed by reduced pressure drying for more than 20 hours. Then, the number of atoms constituting the film (excluding hydrogen) was determined using X-ray photoelectron spectroscopy (Quanterar SXM) with AlKa rays as the radiation source. The atomic percentage (R) of the oxygen atoms in the phenolic hydroxyl groups in the resist underlayer film was then calculated using the following formula. OH [atom%]).

[0034]

[0035] F: Number of fluorine atoms

[0036] A: The total number of atoms (excluding hydrogen atoms).

[0037] It should be noted that if the resist film contains fluorine atoms before the vapor phase chemical modification method, these fluorine atoms are not included in the F in the mathematical formula.

[0038] The atomic percentage of oxygen in the phenolic hydroxyl groups of the cured film of the composition can be adjusted by appropriately selecting the amount and type of compound (A) in the composition for forming the resist underlayer film.

[0039] <Compound (A)>

[0040] Compound (A) contains an aromatic hydrocarbon ring with a phenolic hydroxyl group attached.

[0041] Compound (A) can be a low-molecular-weight compound or a high-molecular-weight compound.

[0042] Examples of aromatic hydrocarbon rings include benzene rings, naphthalene rings, anthracene rings, and pyrene rings.

[0043] That is, the so-called "phenolic hydroxyl group" has the same meaning as the hydroxyl group that is directly bound to the aromatic hydrocarbon ring.

[0044] There is no particular limitation on the number of phenolic hydroxyl groups that are bonded to one aromatic hydrocarbon ring; there can be one or more.

[0045] There is no particular limitation on the number of aromatic hydrocarbon rings with phenolic hydroxyl groups in compound (A), which can be one or more.

[0046] From the viewpoint of suitably obtaining the effects of the present invention, phenolic resin, naphthol resin, biphenol resin, polyhydroxystyrene, polyhydroxyvinylnaphthalene, and low molecular weight compounds (A-1) containing four or more phenolic hydroxyl groups and having a molecular weight of 5000 or less are preferred as compound (A-1).

[0047] There are no particular limitations on the molecular weight of compound (A), but for example, the weight-average molecular weight is preferably 100,000 or less, and more preferably 70,000 or less.

[0048] Weight-average molecular weight can be determined, for example, by gel permeation chromatography (GPC).

[0049] <<Phenolic resin, Naphthol resin, Biphenol resin>>

[0050] Phenolic resins, naphthol resins, and biphenol resins (hereinafter sometimes referred to as "phenolic resins") are, for example, resins obtained by condensing phenolic compounds with at least one of aldehyde compounds, ketone compounds, and divinyl compounds under an acid catalyst.

[0051] Examples of phenolic compounds include phenols, naphthols, anthraquinones, and hydroxypyrene.

[0052] Examples of phenols include phenol, cresol, xylenol, resorcinol, biphenol, bisphenol F, bisphenol A, p-tert-butylphenol, p-octylphenol, 9,9-bis(4-hydroxyphenyl)fluorene, and 1,1,2,2-tetra(4-hydroxyphenyl)ethane.

[0053] Examples of naphthols include 1-naphthol, 2-naphthol, 1,5-dihydroxynaphthol, 2,7-dihydroxynaphthol, and 9,9-bis(6-hydroxynaphthyl)fluorene.

[0054] Examples of anthraquinones include 9-anthraquinone.

[0055] Examples of hydroxypyrene derivatives include 1-hydroxypyrene and 2-hydroxypyrene.

[0056] They can be used individually or in combination of two or more.

[0057] They can also have substituents. For example, they can have substituents on aromatic rings.

[0058] Examples of aldehyde compounds include saturated aliphatic aldehydes, unsaturated aliphatic aldehydes, heterocyclic aldehydes, and aromatic aldehydes. Examples of saturated aliphatic aldehydes include formaldehyde, paraformaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, isobutyraldehyde, pentanal, hexanal, 2-methylbutyraldehyde, hexanal, undecanoal, 7-methoxy-3,7-dimethyloctaldehyde, cyclohexanal, 3-methyl-2-butanal, 2-ethylhexanal, glyoxal, malondialdehyde, succinaldehyde, glutaraldehyde, and adipaldehyde. Examples of unsaturated aliphatic aldehydes include acrolein and methacrolein. Examples of heterocyclic aldehydes include furfural and pyridinaldehyde. Examples of aromatic aldehydes include benzaldehyde, naphthylaldehyde, anthraceneylaldehyde, phenanthrenealdehyde, salicylaldehyde, phenylacetaldehyde, 3-phenylpropionaldehyde, methylbenzaldehyde, (N,N-dimethylamino)benzaldehyde, and acetoxybenzaldehyde. Among them, saturated aliphatic aldehydes and aromatic aldehydes are preferred.

[0059] Examples of ketone compounds include diaryl ketones, such as diphenyl ketones, phenylnaphthyl ketones, dinaphthyl ketones, phenyltolyl ketones, and xylyl ketones.

[0060] Examples of divinyl compounds include divinylbenzene, dicyclopentadiene, tetrahydroindene, 4-vinylcyclohexene, 5-vinyl-2-norbornene, divinylpyrene, limonene, and 5-vinylnorbornadiene.

[0061] They can be used individually or in combination of two or more.

[0062] Phenolic resins preferably contain the structural unit shown in the following formula (1).

[0063]

[0064] In equation (1), R 1 Substituents that represent substitutions on the ring can be halogen atoms, nitro, cyano, amino, substituted alkyl, substituted alkenyl, or substituted aryl groups, each representing a halogen atom, nitro group, cyano group, amino group, substituted alkyl group, substituted alkenyl group, or substituted aryl group.

[0065] R 2 It represents a hydrogen atom, a substituted aryl group, or a substituted heteroaryl group.

[0066] R 3 It represents a hydrogen atom, a substituted alkyl group, a substituted aryl group, or a substituted heteroaryl group.

[0067] R 2 The group and R 3 The groups can combine with each other to form divalent groups.

[0068] Examples of substituents for aryl and heteroaryl groups include halogen atoms, nitro groups, cyano groups, amino groups, hydroxyl groups, carboxyl groups, alkyl groups, and alkenyl groups.

[0069] Ar 1 It indicates a benzene ring, naphthalene ring, or biphenyl structure.

[0070] h 1 Each can independently represent an integer from 0 to 4.

[0071] k 1 Each can independently represent an integer from 1 to 4.

[0072] Ar 1 When it is a benzene ring, h 1 With k 1 The total is less than 4, Ar 1 When it is a naphthalene ring, h 1 With k 1 The total is less than 6, Ar 1 When it is a biphenyl structure, h 1 With k 1 The total is less than 8.

[0073] The following are specific examples of the structural units shown in equation (1), but are not limited to these.

[0074]

[0075] The following are specific examples of phenols, but are not limited to these.

[0076]

[0077] n represents an integer from 0 to 4.

[0078] Examples of phenols include NeoFARIT 7177C ( (Company name) NeoFARIT V002-EA2 ( (Company name) NeoFARIT V003 ( (Company name) etc.

[0079] As mentioned above, phenols are, for example, resins obtained by condensing phenolic compounds with at least one of aldehyde, ketone, and divinyl compounds under an acid catalyst.

[0080] In this condensation reaction, for example, an aldehyde or ketone compound is typically used in a ratio of 0.1 to 10 equivalents relative to 1 equivalent of the benzene ring constituting the phenolic compound.

[0081] In the above condensation reaction, an acid catalyst is usually used.

[0082] Examples of acid catalysts include inorganic acids such as sulfuric acid, phosphoric acid, and perchloric acid; organic sulfonic acids such as p-toluenesulfonic acid and p-toluenesulfonic acid monohydrate; and carboxylic acids such as formic acid and oxalic acid, but are not limited to these.

[0083] The amount of acid catalyst is appropriately determined according to the type of acid used, etc., so it cannot be generalized, but it is usually appropriately determined from the range of 0.001 to 10,000 parts by mass relative to 100 parts by mass of phenolic compound.

[0084] The above condensation reaction can sometimes be carried out without a solvent if either the raw material compound or the acid catalyst used is liquid, but it is usually carried out with a solvent.

[0085] There are no particular limitations on such solvents as long as they do not hinder the reaction, but typical examples include ether compounds and ether ester compounds.

[0086] Examples of ether compounds include tetrahydrofuran and dioxane, which are cyclic ether compounds.

[0087] Examples of ether ester compounds include methyl cellolytic acetate, ethyl cellolytic acetate, butyl cellolytic acetate, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monomethyl ether propionate, propylene glycol monoethyl ether propionate, and propylene glycol monopropyl ether propionate.

[0088] The reaction temperature is usually appropriately determined within the range of 40℃ to 200℃. The reaction time varies depending on the reaction temperature and therefore cannot be generalized, but it is usually appropriately determined within the range of 30 minutes to 50 hours.

[0089] After the reaction is complete, if necessary, the phenols are purified and separated using conventional methods, and the resulting phenols are used to prepare compositions for forming the lower layer of the resist film.

[0090] If one is skilled in the art, one can determine the manufacturing conditions for phenols without undue burden based on the above description and common technical knowledge, and thus phenols can be manufactured.

[0091] <<Polyhydroxystyrene>>

[0092] Polyhydroxystyrene includes polyhydroxystyrene and polyhydroxystyrene derivatives.

[0093] Examples of polyhydroxystyrene or polyhydroxystyrene derivatives include poly(o-hydroxystyrene), poly(m-hydroxystyrene), poly(p-hydroxystyrene), poly(α-methylo-hydroxystyrene), poly(α-methylm-hydroxystyrene), and poly(α-methylp-hydroxystyrene).

[0094] Polyhydroxystyrene or its derivatives can be homopolymers of hydroxystyrene that may have substituents, or copolymers obtained by copolymerizing hydroxystyrene that may have substituents with other compounds. Examples of other compounds include: (meth)acrylic acid, (meth)acrylic acid derivatives described later; acrylonitrile, methacrylonitrile; or styrene, α-methylstyrene, p-methylstyrene, o-methylstyrene, p-methoxystyrene, p-chlorostyrene, and other styrene derivatives.

[0095] Polyhydroxystyrene can be obtained by polymerizing hydroxystyrene that can have substituents, for example preferably having the structural unit shown in the following formula (2).

[0096]

[0097] (In formula (2), R represents a halogen atom, carboxyl group, nitro group, cyano group, methylenedioxy group, acetoxy group, methylthio group, amino group, or alkoxy group with 1 to 9 carbon atoms. n represents an integer from 0 to 4. When n is 2 or more, the n Rs can be the same or different.)

[0098] In this specification, fluorine, chlorine, bromine and iodine atoms can be cited as halogen atoms.

[0099] In this specification, examples of alkoxy groups having 1 to 9 carbon atoms include methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, n-pentoxy, 1-methyl-n-butoxy, 2-methyl-n-butoxy, 3-methyl-n-butoxy, 1,1-dimethyl-n-propoxy, 1,2-dimethyl-n-propoxy, 2,2-dimethyl-n-propoxy, 1-ethyl-n-propoxy, n-hexyloxy, 1-methyl-n-pentoxy, 2-methyl-n-pentoxy, 3-methyl-n-pentoxy, 4 -Methyl-n-pentoxy, 1,1-dimethyl-n-butoxy, 1,2-dimethyl-n-butoxy, 1,3-dimethyl-n-butoxy, 2,2-dimethyl-n-butoxy, 2,3-dimethyl-n-butoxy, 3,3-dimethyl-n-butoxy, 1-ethyl-n-butoxy, 2-ethyl-n-butoxy, 1,1,2-trimethyl-n-propoxy, 1,2,2,-trimethyl-n-propoxy, 1-ethyl-1-methyl-n-propoxy, 1-ethyl-2-methyl-n-propoxy, n-heptoxy, n-octoxy, and n-nonoxy.

[0100] Examples of (meth)acrylic acid derivatives that are used as copolymer components include methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, pentyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate, 2-ethylhexyl methacrylate, nonyl methacrylate, decyl methacrylate, undecyl methacrylate, dodecyl methacrylate, trifluoroethyl methacrylate, and tetrafluoropropyl methacrylate, as well as acrylamides such as diacetone acrylamide; tetrahydrofurfuryl methacrylate, dialkylaminoethyl methacrylate, and glycidyl methacrylate, etc.

[0101] <<Polyhydroxyvinylnaphthalene>>

[0102] Polyhydroxyvinylnaphthalene includes polyhydroxyvinylnaphthalene and polyhydroxyvinylnaphthalene derivatives.

[0103] Polyhydroxyvinylnaphthalene or its derivatives can be homopolymers of hydroxyvinylnaphthalene that may have substituents, or copolymers obtained by copolymerizing hydroxyvinylnaphthalene that may have substituents with other compounds. Examples of other compounds include: (meth)acrylic acid, the aforementioned (meth)acrylic acid derivatives; acrylonitrile, methacrylonitrile; or styrene, α-methylstyrene, p-methylstyrene, o-methylstyrene, p-methoxystyrene, p-chlorostyrene, and other styrene derivatives.

[0104] Polyhydroxyvinylnaphthalenes can be obtained by polymerizing hydroxyvinylnaphthalenes that may have substituents, for example preferably having the structural unit shown in the following formula (3).

[0105]

[0106] (In formula (3), R represents a halogen atom, carboxyl group, nitro group, cyano group, methylenedioxy group, acetoxy group, methylthio group, amino group, or alkoxy group with 1 to 9 carbon atoms. n represents an integer from 0 to 6. When n is 2 or more, the n Rs can be the same or different.)

[0107] <<Low molecular weight compound (A-1)>>

[0108] As a low molecular weight compound (A-1), there are no special restrictions as long as it contains two or more phenolic hydroxyl groups and has a molecular weight of less than 5000.

[0109] The number of phenolic hydroxyl groups in the low molecular weight compound (A-1) is 2 or more, preferably 3 to 50, and more preferably 4 to 30.

[0110] The molecular weight of the low molecular weight compound (A-1) is 5000 or less, preferably 200 to 4000, and more preferably 300 to 3000.

[0111] From the viewpoint of suitably obtaining the effects of the present invention, the compounds shown in formula (A-1-1), (A-1-2), (A-1-3), and (A-1-4) are preferred as low molecular weight compounds (A-1).

[0112] <<<Compounds represented by formula (A-1-1)>>>

[0113] (In formula (A-1-1), Z) 1 Groups representing p-valence.

[0114] p represents an integer from 2 to 4.

[0115] X represents an organic group represented by the following formula (X) independently.

[0116]

[0117] (In formula (X), R1 represents an alkylene group with 1 to 4 carbon atoms.)

[0118] T represents a single bond or a hydrocarbon group with a (s+1) valence and 1 to 8 carbon atoms.

[0119] A1 to A3 each independently represent a hydrogen atom, a methyl group, or an ethyl group.

[0120] k represents 0 or 1.

[0121] m represents an integer from 0 to 4.

[0122] n represents 0 or 1.

[0123] q represents 0 or 1.

[0124] s represents 1 or 2.

[0125] * indicates Z in equation (A-1-1) 1 The combined part.

[0126] (When T is a single bond, n and q are not both 1.)

[0127] Z in equation (A-1-1) 1 There are no particular restrictions as long as the group is p-valent, but it is preferred to be represented by the following formula (Z-1).

[0128]

[0129] (In equation (Z-1), Q3 represents the following equations (Z-1-1), (Z-1-2), (Z-1-3), or (Z-1-4).

[0130] *Each represents the part that relates to X in equation (A-1-1).

[0131] (In equations (Z-1-1), (Z-1-2), (Z-1-3), and (Z-1-4), R 11 ~R 15 Each of the following can independently represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms that can be interrupted by an oxygen atom or a sulfur atom, an alkenyl group having 2 to 10 carbon atoms that can be interrupted by an oxygen atom or a sulfur atom, an alkynyl group having 2 to 10 carbon atoms that can be interrupted by an oxygen atom or a sulfur atom, a benzyl group, or a phenyl group. The phenyl group can be substituted with at least one monovalent functional group selected from alkyl groups having 1 to 6 carbon atoms, halogen atoms, alkoxy groups having 1 to 10 carbon atoms, nitro groups, cyano groups, and alkylthio groups having 1 to 6 carbon atoms.

[0132] * indicates a bonding bond. *1 indicates a bonding bond with the nitrogen atom in formula (Z-1). *2 indicates a bonding bond with the carbon atom in formula (Z-1). *3 indicates a bonding portion with X in formula (A-1-1).

[0133] In equation (Z-1), Q3 represents R in equation (Z-1-1). 11 and R 12 Preferably, each is an alkyl group having 1 to 10 carbon atoms.

[0134] In equation (Z-1), Q3 represents R in equation (Z-1-2). 13 and R 14 Preferably, each is an alkyl group having 1 to 10 carbon atoms.

[0135] In formula (Z-1), Q3 is preferably formula (Z-1-3) or formula (Z-1-4).

[0136] R in equation (Z-1-3) 15 Preferably, it is an alkyl group with 1 to 10 carbon atoms that can be interrupted by oxygen or sulfur atoms, or an alkenyl group with 2 to 10 carbon atoms that can be interrupted by oxygen or sulfur atoms; more preferably, it is an alkyl group with 1 to 10 carbon atoms or an alkenyl group with 2 to 10 carbon atoms.

[0137] The compound shown in formula (A-1-1) can be obtained by reacting, for example, the compounds shown in formulas (a) to (w) and (ac) to (aj) below with the compound shown in formula (Y) below using known methods, but is not limited to these.

[0138]

[0139] (In formula (Y), m represents an integer from 0 to 4. k represents 0 or 1.)

[0140] Examples of compounds represented by formula (Y) include the following.

[0141]

[0142] Examples of compounds represented by formula (A-1-1) include the following compounds.

[0143]

[0144] <<<Compounds shown in formula (A-1-2)>>>

[0145] (In formula (A-1-2), Ar 1 ~Ar 3 Each can be used independently to represent an aromatic hydrocarbon ring.

[0146] n1 to n3 each independently represent integers from 1 to 4.

[0147] Examples of aromatic hydrocarbon rings include benzene rings, naphthalene rings, and anthracene rings. Among these, benzene rings and naphthalene rings are preferred.

[0148] n1 to n3 are preferably 1.

[0149] Examples of compounds that can be cited as compounds represented by formula (A-1-2) include the following compounds.

[0150]

[0151] The compound shown in formula (A-1-2) can be synthesized, for example, by reacting phloroglucinol of formula (A-1-2A) with the compound of formula (A-1-2B). In the reaction, a protecting group of the hydroxyl group may be used if necessary, and deprotection may be performed.

[0152]

[0153] (In formula (A-1-2B), Ar represents an aromatic hydrocarbon ring.)

[0154] R represents a protecting group for a hydrogen atom or a hydroxyl group.

[0155] n1 represents an integer from 1 to 4.

[0156] Examples of aromatic hydrocarbon rings include benzene rings, naphthalene rings, and anthracene rings. Among these, benzene rings and naphthalene rings are preferred.

[0157] Examples of compounds represented by formula (A-1-2B) include tert-butoxystyrene and 2-tert-butoxyvinylnaphthalene.

[0158] <<<Compounds shown in formula (A-1-3)>>>

[0159] (In formula (A-1-3), T represents a single bond, an alkylene group with 1 to 10 carbon atoms, or an aryl group with 6 to 40 carbon atoms.)

[0160] X 1 and X 2 Each can be used independently to represent a hydrogen atom or a methyl group.

[0161] R 5 ~R 8 Each can be independently represented as an alkyl group with 1 to 10 carbon atoms or an aryl group with 6 to 40 carbon atoms.

[0162] n1 to n4 each independently represent integers from 0 to 3.

[0163] Examples of compounds that can be cited as compounds represented by formula (A-1-3) include the following compounds.

[0164]

[0165] The compound shown in formula (A-1-3) can also be a commercially available product. Examples of commercially available products include TEP-TPA (manufactured by Asahi Organic Materials Co., Ltd.).

[0166] <<<Compounds shown in formula (A-1-4)>>>

[0167] The compound shown in formula (A-1-4) is tannic acid.

[0168]

[0169] The content of compound (A) in the composition for forming the lower layer of the resist film is not particularly limited, but from the viewpoint of suitably obtaining the effects of the present invention, it is preferably 40% to 99% by mass, more preferably 45% to 95% by mass, and particularly preferably 50% to 90% by mass, relative to the film composition.

[0170] It should be noted that, in this invention, the term "film constituents" refers to the components contained in the composition other than the solvent.

[0171] <Solvent (B)>

[0172] As a solvent (B), there are no particular restrictions; it can be water or an organic solvent.

[0173] Examples of organic solvents include monoalkylene glycol ethers and monocarboxylic acid esters of monoalkylene glycol ethers.

[0174] Examples of alkylene groups that are monoalkylene glycol ethers include alkylene groups with 2 to 4 carbon atoms.

[0175] Examples of alkyl groups that are monoalkylene glycol ethers include alkyl groups having 1 to 4 carbon atoms.

[0176] Examples of alkylene glycol monoalkyl ethers with 3 to 8 carbon atoms are given.

[0177] Examples of alkylene glycol monoalkyl ethers include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, and propylene glycol monoethyl ether.

[0178] Examples of alkylene compounds that are monocarboxylic acid esters of alkylene glycol monoalkyl ethers include alkylene compounds with 2 to 4 carbon atoms.

[0179] Examples of alkyl groups that are monocarboxylic acid esters of alkylene glycol monoalkyl ethers include alkyl groups having 1 to 4 carbon atoms.

[0180] Monocarboxylic acids that are monocarboxylic acid esters of alkylene glycol monoalkyl ethers include saturated monocarboxylic acids with 2 to 4 carbon atoms.

[0181] Examples of saturated monocarboxylic acids with 2 to 4 carbon atoms include acetic acid, propionic acid, and butyric acid.

[0182] Examples of monocarboxylic acid esters that are monoalkylene glycol monoalkyl ethers include, for example, 5 to 10 carbon atoms.

[0183] Examples of monocarboxylic acid esters that are monoalkylene glycol monoalkyl ethers include methyl cellolytic acetate, ethyl cellolytic acetate, propylene glycol monomethyl ether acetate, and propylene glycol propyl ether acetate.

[0184] Other organic solvents include, for example, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, cycloheptanone, 4-methyl-2-pentanol, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate, ethyl ethoxylate, 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, N,N-dimethylacetamide, etc.

[0185] Among these solvents (B), monoalkylene glycol monoalkyl ethers and monocarboxylic acid esters of monoalkylene glycol monoalkyl ethers are preferred.

[0186] These solvents (B) can be used alone or in combination of two or more.

[0187] The mass ratio of the organic solvent in solvent (B) is not particularly limited, but is preferably 50% to 100% by mass.

[0188] The content of solvent (B) in the composition for forming the lower layer of the resist film is not particularly limited, but is preferably 50% to 99.99% by mass, more preferably 75% to 99.95% by mass, and particularly preferably 90% to 99.9% by mass.

[0189] <Crosslinking agent (C)>

[0190] There are no particular restrictions on its use as a crosslinking agent (C).

[0191] The crosslinking agent (C) has a different structure from compound (A).

[0192] As a crosslinking agent (C), amino plastic crosslinking agents and phenolic plastic crosslinking agents are preferred.

[0193] Amino plastic crosslinking agents are addition condensations of amino compounds such as melamine and melamine with formaldehyde.

[0194] Phenolic plastic crosslinking agents are addition condensation compounds of compounds with phenolic hydroxyl groups and formaldehyde.

[0195] Examples of crosslinking agents (C) include compounds having two or more of the following structures.

[0196]

[0197] (In the structure, R) 101 This indicates a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an alkoxyalkyl group having 2 to 6 carbon atoms. * indicates a bonding bond.

[0198] Bonding bonds include, for example, bonds with nitrogen atoms or carbon atoms that form aromatic hydrocarbon rings.

[0199] As R 101 Preferably, it contains hydrogen atoms, methyl, ethyl or groups represented by the following structures.

[0200]

[0201] (In the structure, R) 102 * Represents a hydrogen atom, methyl group, or ethyl group. * Represents a bond.

[0202] As a crosslinking agent (C), melamine compounds, melamine diamine compounds, glycourea compounds, urea compounds, and compounds with phenolic hydroxyl groups are preferred. One of them may be used alone or in combination of two or more.

[0203] Examples of melamine compounds include hexahydroxymethyl melamine, hexamethoxymethyl melamine, compounds of hexahydroxymethyl melamine in which 1 to 6 hydroxymethyl groups are methoxymethylated, or mixtures thereof, hexamethoxyethyl melamine, hexaacyloxymethyl melamine, compounds of hexahydroxymethyl melamine in which 1 to 6 acyloxymethyl groups are methoxymethylated, or mixtures thereof.

[0204] Examples of melamine compounds include tetrahydroxymethyl melamine, tetramethoxymethyl melamine, compounds of tetrahydroxymethyl melamine in which 1 to 4 hydroxymethyl groups are methoxymethylated, or mixtures thereof, tetramethoxyethyl melamine, tetraacyloxymelamine, compounds of tetrahydroxymethyl melamine in which 1 to 4 hydroxymethyl groups are acyloxymethylated, or mixtures thereof.

[0205] Examples of glycourea compounds include tetrahydroxymethylglycourea, tetramethoxyglycourea, tetramethoxymethylglycourea, compounds of tetrahydroxymethylglycourea in which 1 to 4 of the hydroxymethyl group are methoxymethylated, or mixtures thereof, and compounds of tetrahydroxymethylglycourea in which 1 to 4 of the hydroxymethyl group are acylmethylated, or mixtures thereof.

[0206] Alternatively, the glycourea compound may be, for example, a glycourea derivative as shown in the following formula (1E).

[0207]

[0208] (In formula (1E), each of the four R1s independently represents a methyl or ethyl group, and each of the R2 and R3 independently represents a hydrogen atom, an alkyl group with 1 to 4 carbon atoms, or a phenyl group.)

[0209] Examples of compounds shown in formula (1E) to (1E-6) below are glycourea derivatives shown in the above formula (1E).

[0210]

[0211] The glycourea derivative shown in formula (1E) can be obtained by reacting, for example, the glycourea derivative shown in formula (2E) below with at least one compound shown in formula (3d) below.

[0212]

[0213] (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.)

[0214] (In formula (3d), R1 represents methyl or ethyl.)

[0215] Examples of compounds shown in formula (2E) to (2E-4) below are examples of glycourea derivatives. Furthermore, examples of compounds shown in formula (3d) below are examples of compounds shown in formula (3d-1) and (3d-2).

[0216]

[0217] Examples of urea compounds include tetrahydroxymethylurea, tetramethoxymethylurea, compounds of tetrahydroxymethylurea in which 1 to 4 hydroxymethyl groups are methoxymethylated, or mixtures thereof, and tetramethoxyethylurea.

[0218] Examples of compounds having phenolic hydroxyl groups include compounds represented by formula (G-1) or formula (G-2) below.

[0219]

[0220] (In equations (G-1) and (G-2), Q) 1 Organic groups that represent single bonds or m1 valence.

[0221] R 1 and R 4 Each represents an alkyl group having 2 to 10 carbon atoms, or an alkyl group having 2 to 10 carbon atoms and an alkoxy group having 1 to 10 carbon atoms.

[0222] R 2 and R 5 Each represents a hydrogen atom or a methyl group.

[0223] R 3 and R 6 Each represents an alkyl group with 1 to 10 carbon atoms, or an aryl group with 6 to 40 carbon atoms.

[0224] n1 represents an integer where 1 ≤ n1 ≤ 3, n2 represents an integer where 2 ≤ n2 ≤ 5, n3 represents an integer where 0 ≤ n3 ≤ 3, n4 represents an integer where 0 ≤ n4 ≤ 3, and n1, n2, n3, and n4 represent integers where 3 ≤ (n1 + n2 + n3 + n4) ≤ 6.

[0225] n5 represents an integer where 1 ≤ n5 ≤ 3, n6 represents an integer where 1 ≤ n6 ≤ 4, n7 represents an integer where 0 ≤ n7 ≤ 3, n8 represents an integer where 0 ≤ n8 ≤ 3, and n5, n6, n7, and n8 represent integers where 2 ≤ (n5 + n6 + n7 + n8) ≤ 5.

[0226] m1 represents an integer from 2 to 10.

[0227] In addition, compounds having phenolic hydroxyl groups can be exemplified by compounds shown in formula (G-3) or formula (G-4) below.

[0228] The compounds shown in formula (G-1) or (G-2) can also be obtained by reacting the compounds shown in formula (G-3) or (G-4) below with ether compounds containing hydroxyl groups or alcohols having 2 to 10 carbon atoms.

[0229]

[0230] (In equations (G-3) and (G-4), Q) 2 Organic groups that represent single bonds or m2 valence.

[0231] R 8 R 9 R 11 and R 12 Each represents a hydrogen atom or a methyl group.

[0232] R 7 and R 10 Each represents an alkyl group with 1 to 10 carbon atoms, or an aryl group with 6 to 40 carbon atoms.

[0233] n9 represents an integer where 1 ≤ n9 ≤ 3, and n 10 It means 2≤n 10 Integers ≤ 5, n 11 It means 0≤n 11 Integers ≤3, n12 It means 0≤n 12 Integers ≤ 3, and n = 9, n 10 n 11 n 12 This means 3 ≤ (n9 + n) 10 +n 11 +n 12 Integers ≤ 6.

[0234] n 13 It means 1≤n 13 Integers ≤3, n 14 It means 1≤n 14 Integers ≤ 4, n 15 It means 0≤n 15 Integers ≤3, n 16 It means 0≤n 16 Integers ≤ 3, and n 13 n 14 n 15 n 16 It means 2≤(n) 13 +n 14 +n 15 +n 16 Integers ≤ 5.

[0235] m2 represents an integer from 2 to 10.

[0236] As Q 2 Examples of m2 valence organic groups include those with 1 to 4 carbon atoms.

[0237] Examples of compounds represented by formula (G-1) or formula (G-2) include the following compounds.

[0238]

[0239] Examples of compounds represented by formula (G-3) or formula (G-4) include the following compounds.

[0240]

[0241] (In the above formula, Me represents methyl.)

[0242] The above-mentioned compounds can be obtained as products manufactured by Asahi Organic Materials Co., Ltd. and Honshu Chemical Co., Ltd. For example, Asahi Organic Materials Co., Ltd.'s trade name TMOM-BP can be cited as an example of such a product.

[0243] Among them, glycourea compounds are preferred, specifically tetrahydroxymethylglycourea, tetramethoxyglycourea, tetramethoxymethylglycourea, a compound or mixture thereof in which one to four of the hydroxymethyl groups of tetrahydroxymethylglycourea are methoxymethylated, a compound or mixture thereof in which one to four of the hydroxymethyl groups of tetrahydroxymethylglycourea are acylmethylated, and more preferably tetramethoxymethylglycourea.

[0244] The molecular weight of the crosslinking agent (C) is not particularly limited, but is preferably 500 or less.

[0245] The content of the crosslinking agent (C) in the composition for forming the lower layer of the resist film is not particularly limited, but is, for example, 1% to 70% by mass, preferably 5% to 60% by mass, relative to compound (A).

[0246] <Cure Catalyst (D)>

[0247] The curing catalyst (D) included as an optional component in the composition for forming the lower layer film of the resist can be either a thermally generated acid agent or a photo-generated acid agent, but a thermally generated acid agent is preferred.

[0248] Examples of heat-generating acid agents include p-toluenesulfonic acid, trifluoromethanesulfonic acid, and pyridine. p-Toluenesulfonate (p-Toluenesulfonic acid pyridine) ), Pyridine phenolsulfonate pyridine p-hydroxybenzenesulfonic acid (pyridine p-phenolsulfonate) (salt), pyridine trifluoromethanesulfonate Sulfonic acid compounds and carboxylic acid compounds, such as salicylic acid, camphor sulfonic acid, 5-sulfosalicylic acid, 4-chlorobenzenesulfonic acid, 4-hydroxybenzenesulfonic acid, benzene disulfonic acid, 1-naphthalenesulfonic acid, citric acid, benzoic acid, hydroxybenzoic acid, N-methylmorpholine-p-toluenesulfonic acid, N-methylmorpholine-p-hydroxybenzenesulfonic acid, and N-methylmorpholine-5-sulfosalicylic acid.

[0249] Examples of photoacid-producing agents include: Salt compounds, sulfonylimide compounds, and disulfonyldiazomethane compounds, etc.

[0250] As Salt compounds, for example, diphenyliodine Hexafluorophosphate, diphenyliodine Trifluoromethanesulfonate, diphenyliodine Nonafluoro-n-butane sulfonate, diphenyl iodide Perfluorooctane sulfonate, diphenyl iodide Camphor sulfonate, bis(4-tert-butylphenyl)iodine Camphor sulfonate and bis(4-tert-butylphenyl)iodine Iodine, such as trifluoromethanesulfonate Sulfonate compounds, and sulfonate compounds such as triphenylsulfonium hexafluoroantimonate, triphenylsulfonium nonafluoro n-butane sulfonate, triphenylsulfonium camphor sulfonate, and triphenylsulfonium trifluoromethane sulfonate.

[0251] Examples of sulfonylimide compounds include N-(trifluoromethanesulfonyloxy)succinimide, N-(nonafluoron-butanesulfonyloxy)succinimide, N-(camphorsulfonyloxy)succinimide, and N-(trifluoromethanesulfonyloxy)naphthalenediformimide.

[0252] Examples of disulfonyl diazonium compounds include bis(trifluoromethylsulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, bis(phenylsulfonyl)diazomethane, bis(p-toluenesulfonyl)diazomethane, bis(2,4-dimethylbenzenesulfonyl)diazomethane, and methylsulfonyl-p-toluenesulfonyl diazonium.

[0253] The curing catalyst (D) can be used alone or in combination of two or more.

[0254] When using a curing catalyst (D), the content of the curing catalyst (D) relative to the crosslinking agent (C) is, for example, 0.1% to 50% by mass, preferably 1% to 30% by mass.

[0255] <Other Ingredients>

[0256] To prevent pinholes, streaks, and other defects, and to further improve the coating properties against surface unevenness, a surfactant may be added to the composition for forming the underlayer film of the resist.

[0257] Examples of surfactants include nonionic surfactants such as polyoxyethylene alkyl ethers (e.g., polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene oil-based ether), polyoxyethylene alkyl aryl ethers (e.g., polyoxyethylene octylphenol ether, polyoxyethylene nonylphenol ether), polyoxyethylene / polyoxypropylene block copolymers, sorbitol monolaurate, sorbitol monopalmitate, sorbitol monostearate, sorbitol monooleate, sorbitol monooleate, sorbitol trioleate, sorbitol tristearate, etc. EF301, EF303, EF352 ((Strain) (Product name, product name) F171, F173, R-30 (manufactured by DIC Corporation, trade name) FC430, FC431 ( (Company name, trade name) AG710 Fluorinated surfactants such as S-382, SC101, SC102, SC103, SC104, SC105, and SC106 (manufactured by AGC Corporation, trade name), and organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), etc.

[0258] The amount of these surfactants mixed in is typically 2.0% by mass or less, preferably 1.0% by mass or less, relative to the total solid content of the composition for forming the underlayer film of the resist.

[0259] These surfactants can be added individually or in combination of two or more.

[0260] The solid component contained in the resist lower film forming composition of the present invention, that is, the component after removing the above-mentioned solvent, is, for example, 0.01% to 10% by mass.

[0261] The resist underlayer film formation composition of the present invention is preferably an EUV (extreme ultraviolet) or electron beam lithography resist underlayer film formation composition.

[0262] It should be noted that, for example, compositions for forming a resist underlayer do not contain light absorbers.

[0263] Additionally, for example, compositions for forming a resist underlayer do not contain polymers having -NH-C(=S)-O- bonds.

[0264] In addition, for example, compositions for forming a resist underlayer do not contain polymers having structural units as shown in the following formula (Z-1).

[0265]

[0266] In addition, for example, compositions for forming a resist underlayer do not contain polymers having structural units as shown in the following formula (Z-2).

[0267]

[0268] (In formula (Z-2), R independently represents either a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.)

[0269] (Underlying film of the resist)

[0270] The resist underlayer film of the present invention is a cured product of the aforementioned resist underlayer film forming composition.

[0271] The resist underlayer film can be manufactured, for example, by coating the aforementioned resist underlayer film forming composition onto a semiconductor substrate and then firing it.

[0272] In the lower layer of the resist film, the atomic percentage of oxygen in the phenolic hydroxyl groups is, for example, 2.00% or more, preferably 2.00% or more and 30.00% or less, more preferably 3.00% or more and 20.00% or less.

[0273] The atomic percentage of oxygen in the phenolic hydroxyl groups of the underlying resist film can be determined, for example, by the following method.

[0274] The silicon wafer with the resist underlayer film was cut to approximately 0.5 × 1 cm and dried under reduced pressure for more than 20 hours. Then, it was sealed in a 6.0 × 7.5 cm weighing bottle with 3 ml of trifluoroacetic anhydride, and the hydrogen atoms of the phenolic hydroxyl groups were replaced with trifluoroacetyl groups by gas-phase chemical modification at 25°C. The reaction time was set according to the time required for each composition to reach reaction equilibrium. Unreacted trifluoroacetic anhydride and trifluoroacetic acid generated as a byproduct were further removed by reduced pressure drying for more than 20 hours. Then, the number of atoms constituting the film (excluding hydrogen) was determined using X-ray photoelectron spectroscopy (Quanterar SXM) with AlKa rays as the radiation source. The atomic percentage (R0) of oxygen in the phenolic hydroxyl groups in the resist underlayer film was then calculated using the following formula. OH [atom%]).

[0275]

[0276] F: Number of fluorine atoms

[0277] A: The total number of atoms (excluding hydrogen atoms).

[0278] It should be noted that if the resist film before the vapor phase chemical modification method has fluorine atoms, these fluorine atoms are not included in the F in the mathematical formula.

[0279] Examples of semiconductor substrates that can be used to form a composition for coating a resist underlayer include silicon wafers, germanium wafers, and compound semiconductor wafers such as gallium arsenide, indium phosphide, gallium nitride, indium nitride, and aluminum nitride.

[0280] When using a semiconductor substrate with an inorganic film formed on its surface, the inorganic film is formed, for example, by ALD (atomic layer deposition), CVD (chemical vapor deposition), reactive sputtering, ion plating, vacuum evaporation, or spin coating (SOG). Examples of such inorganic films include polycrystalline silicon films, silicon oxide films, silicon nitride films, BPSG (boro-phosphorus silicon glass) films, titanium nitride films, titanium oxide nitride films, tungsten films, gallium nitride films, and gallium arsenide films.

[0281] On such a semiconductor substrate, the resist underlayer film formation composition of the present invention is coated using a suitable coating method such as a spin coater or a coating machine. Then, it is baked using a heating means such as a heating plate to form the resist underlayer film. The baking conditions are appropriately selected from a baking temperature of 100°C to 400°C and a baking time of 0.3 minutes to 60 minutes. Preferably, the baking temperature is 120°C to 350°C and the baking time is 0.5 minutes to 30 minutes; more preferably, the baking temperature is 150°C to 300°C and the baking time is 0.8 minutes to 10 minutes.

[0282] The thickness of the underlying resist film is, for example, 0.001 μm (1 nm) to 10 μm, 0.002 μm (2 nm) to 1 μm, 0.005 μm (5 nm) to 0.5 μm (500 nm), 0.001 μm (1 nm) to 0.05 μm (50 nm), 0.002 μm (2 nm) to 0.05 μm (50 nm), 0.003 μm (3 nm) to 0.05 μm (50 nm), 0.004 μm (4 nm) to 0.05 μm (50 nm), 0.005 μm (5 nm) to 0.05 μm (… 50nm), 0.003μm (3nm)~0.03μm (30nm), 0.003μm (3nm)~0.02μm (20nm), 0.005μm (5nm)~0.02μm (20nm), 0.005μm (5nm)~0.02μm (20nm), 0.003μm (3nm)~0.01μm (10nm), 0.005μm (5nm)~0.01μm (10nm), 0.003μm (3nm)~0.006μm (6nm) or 0.005μm (5nm).

[0283] From the viewpoint of achieving the desired effects of the present invention, the thickness of the resist underlayer film is preferably 2 nm or more and 20 nm or less.

[0284] The method for determining the thickness of the resist underlayer film in this specification is as follows.

[0285] • Measuring device name: Elliptic film thickness measuring device RE-3100 (SCREEN Co., Ltd.)

[0286] • SWE (Single Wavelength Ellipsometry) Mode

[0287] • Arithmetic mean of 8 points (e.g., measured at 1cm intervals in the X direction of the wafer).

[0288] (Laminated body)

[0289] The stack of the present invention comprises a semiconductor substrate and a photoresist underlayer film of the present invention.

[0290] Examples of semiconductor substrates include those mentioned above.

[0291] The photoresist underlayer is, for example, disposed on a semiconductor substrate.

[0292] (Semiconductor device manufacturing methods and patterning methods)

[0293] The method for manufacturing the semiconductor device of the present invention includes at least the following steps.

[0294] • The process of forming a photoresist underlayer film on a semiconductor substrate using the photoresist underlayer film forming composition of the present invention, and

[0295] • The process of forming a resist film on the underlying resist film

[0296] The pattern forming method of the present invention includes at least the following steps.

[0297] • The process of forming a photoresist underlayer film on a semiconductor substrate using the photoresist underlayer film forming composition of the present invention, • The process of forming a resist film on the underlying resist film • The process of irradiating the resist film with light or an electron beam, followed by developing the resist film to obtain the resist pattern, and... • The process of etching the underlying resist film using a resist pattern as a mask. Typically, a resist layer is formed on the lower resist film.

[0298] The thickness of the resist layer is, for example, 3,000 nm or less, 2,000 nm or less, 1,800 nm or less, 1,500 nm or less, or 1,000 nm or less. The lower limit is 100 nm, 80 nm, 50 nm, 30 nm, 20 nm, or 10 nm.

[0299] As a resist film formed on a resist underlayer by known methods (such as coating and firing of the resist composition), there are no particular limitations as long as it responds to the light or electron beam (EB) used for irradiation. Both negative and positive photoresists can be used.

[0300] It should be noted that, in this specification, the EB-responsive resist is also referred to as a photoresist.

[0301] As photoresists, there are positive photoresists composed of phenolic varnish resin and 1,2-naphthoquinone diazonium sulfonate; chemically amplified photoresists composed of binders and photoacid-generating agents with groups that increase the alkali dissolution rate of the photoresist through acid decomposition; chemically amplified photoresists composed of low-molecular-weight compounds that increase the alkali dissolution rate of the photoresist through acid decomposition; alkali-soluble binders and photoacid-generating agents; chemically amplified photoresists composed of binders with groups that increase the alkali dissolution rate of the photoresist through acid decomposition; low-molecular-weight compounds that increase the alkali dissolution rate of the photoresist through acid decomposition; and photoacid-generating agents; as well as photoresists containing metal elements. For example, JSR Corporation's trade name V146G can be cited. The company's product name is APEX-E, Sumitomo Chemical Co., Ltd.'s product name is PAR710, and Shin-Etsu Chemical Co., Ltd.'s product names are AR2772 and SEPR430. In addition, examples of fluorinated polymer photoresists can be cited, 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).

[0302] Alternatively, you can use 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, WO2019 / 172054, W O2019 / 021975, WO2018 / 230334, WO2018 / 194123, Japanese Special Opening 2018-180525, WO2018 / 190088, Japanese Special Opening 2018-070596, Japanese Special Opening 2018-028090, Japanese Special Opening 2016-153409, Japanese Special Opening 2016-130240, Japanese Special Opening 2016-108325, Japanese Special Opening 2016-047920, Japanese Special Opening 2016-035570, Japan Special opening 2016-035567, Japanese special opening 2016-035565, Japanese special opening 2019-101417, Japanese special opening 2019-117373, Japan Special Opening 2019-052294, Japanese Special Opening 2019-008280, Japanese Special Opening 2019-008279, Japanese Special Opening 2019-003176, Japanese Special Opening 2019-003175, Japanese Special Opening 2018-197853, Japanese Special Opening 2019-191298, Japanese Special Opening 2019-06 1217. Japan Special Opening 2018-045152, Japanese Special Opening 2018-022039, Japanese Special Opening 2016-090441, Japanese Special Opening 2015-10878, Japanese Special Opening 2012-168279, Japanese Special Opening 2012-022261, Japanese Special Opening 2012-022258, Japanese Special Opening 201 The so-called resist compositions, such as resist compositions, radiation-sensitive resin compositions, and compositions for high-resolution patterning based on organometallic solutions, as described in 1-043749, Japanese Patent Application Publication No. 2010-181857, Japanese Patent Application Publication No. 2010-128369, WO2018 / 031896, Japanese Patent Application Publication No. 2019-113855, WO2017 / 156388, WO2017 / 066319, Japanese Patent Application Publication No. 2018-41099, WO2016 / 065120, WO2015 / 026482, Japanese Patent Application Publication No. 2016-29498, and Japanese Patent Application Publication No. 2011-253185, are metal-containing resist compositions, but are not limited to these.

[0303] Examples of resist compositions include the following.

[0304] An active light-sensitive or radiation-sensitive resin composition comprising resin A and a compound represented by the following general formula (121), wherein resin A has repeating units having acid-degradable groups that are protected by protecting groups that are deactivated by the action of acid.

[0305]

[0306] In general formula (121), m represents an integer from 1 to 6.

[0307] R1 and R2 each independently represent a fluorine atom or a perfluoroalkyl group.

[0308] L1 represents -O-, -S-, -COO-, -SO2-, or -SO3-.

[0309] L2 indicates that it can have alkylene groups or single bonds that have substituents.

[0310] W1 represents a cyclic organic group that can have substituents.

[0311] M ＋ It represents a cation.

[0312] A metal-containing film-forming composition for 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.

[0313] A radiation-sensitive resin composition comprising a polymer and an acid-producing agent, said polymer having a first structural unit as shown in formula (31) and a second structural unit as shown in formula (32) and containing an acid-dissociating group.

[0314]

[0315] In formula (31), Ar is a group obtained by removing (n+1) hydrogen atoms from an aromatic hydrocarbon with 6 to 20 carbon atoms. 1 It is a hydroxyl group, a thiol group, or a monovalent organic group with 1 to 20 carbon atoms. n is an integer from 0 to 11. When n is 2 or more, multiple R... 1 They can be the same or different. R 2 It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. In formula (32), R 3 It is a monovalent group containing 1 to 20 carbon atoms, including the aforementioned acid-dissociative group. Z is a single bond, an oxygen atom, or a sulfur atom. R 4 (It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.)

[0316] An anti-corrosion composition comprising a resin (A1) and an acid-generating agent, wherein the resin (A1) comprises structural units having a cyclic carbonate structure, structural units shown in the following formula, and structural units having an acid-instantaneous group.

[0317]

[0318] [In the formula,] R 2 X represents an alkyl group, hydrogen atom, or halogen atom with 1 to 6 carbon atoms that can have halogen atoms. 1 Indicates a single bond, -CO-O-*, or -CO-NR 4 -*, * indicates a bond with -Ar, R 4 [Ar represents an alkyl group having 1 to 4 hydrogen atoms or carbon atoms, and an aromatic hydrocarbon group having 6 to 20 carbon atoms that may have one or more groups selected from hydroxyl and carboxyl groups.] Examples of resist films include the following.

[0319] A photoresist film comprising a base resin containing repeating units as shown in formula (a1) and / or repeating units as shown in formula (a2), and repeating units of acid bonded to the polymer backbone by exposure.

[0320]

[0321] (In equations (a1) and (a2), R) A Each can be independently a hydrogen atom or a methyl group. R 1 and R 2 Each is an independent tertiary alkyl group having 4 to 6 carbon atoms. R 3 Each atom can be independently either a fluorine atom or a methyl group. m is an integer from 0 to 4. X 1 It is a linker group having 1 to 12 carbon atoms, consisting of a single bond, a phenylene or naphthylene group, or containing at least one of the following: an ester bond, a lactone ring, a phenylene group, and a naphthylene group. X 2 (These can be single bonds, ester bonds, or amide bonds.)

[0322] Examples of corrosion-resistant materials include the following.

[0323] A corrosion-resistant material comprising a polymer having repeating units as shown in formula (b1) or formula (b2).

[0324]

[0325] (In equations (b1) and (b2), R) A It can be a hydrogen atom or a methyl group. X 1 It is a single bond or an ester group. X2 It is a linear, branched, or cyclic alkylene group with 1 to 12 carbon atoms or an aryl group with 6 to 10 carbon atoms. A portion of the methylene group constituting the alkylene group may be substituted with an ether group, an ester group, or a group containing an lactone ring. Additionally, X 2 At least one hydrogen atom is replaced by a bromine atom. X 3 It is a single bond, an ether group, an ester group, or a straight-chain, branched, or cyclic alkylene group having 1 to 12 carbon atoms, wherein a portion of the methylene group constituting the alkylene group may be substituted with an ether group or an ester group. Rf 1 ~Rf 4 Each atom can be independently a hydrogen atom, a fluorine atom, or a trifluoromethyl atom, but at least one of them must be a fluorine atom or a trifluoromethyl atom. Additionally, Rf... 1 and Rf 2 They can combine to form a carbonyl group. R 1 ~R 5 Each group is independently a linear, branched, or cyclic alkyl group with 1 to 12 carbon atoms, an alkenyl group with 2 to 12 carbon atoms, an alkynyl group with 2 to 12 carbon atoms, an aryl group with 6 to 20 carbon atoms, an aralkyl group with 7 to 12 carbon atoms, or an aryloxyalkyl group with 7 to 12 carbon atoms. Some or all of the hydrogen atoms in these groups may be substituted with hydroxyl, carboxyl, halogen, oxo, cyano, amide, nitro, sulopentalide, sulfonic acid, or a group containing a sulfonate. A portion of the methylene group constituting these groups may be substituted with ether, ester, carbonyl, carbonate, or sulfonate groups. Additionally, R... 1 With R 2 They can combine with the sulfur atoms they are bonded to to form rings.

[0326] An anti-corrosion material comprising a base resin, said base resin comprising a polymer containing repeating units as shown in formula (a).

[0327]

[0328] (In formula (a), R) A It can be a hydrogen atom or a methyl group. R 1 It is a hydrogen atom or an acid-instable group. R 2 It is a linear, branched, or cyclic alkyl group having 1 to 6 carbon atoms, or a halogen atom other than bromine. X 1 It is a single bond or a phenylene group, or a straight-chain, branched, or cyclic alkylene group having 1 to 12 carbon atoms that may contain an ester group or an lactone ring. X 2 It can be -O-, -O-CH2-, or -NH-. m is an integer from 1 to 4. u is an integer from 0 to 3. Where m + u is an integer from 1 to 4.

[0329] A photoresist composition that generates acid upon exposure, thereby altering the solubility of the photoresist in a developer through the action of the acid. It contains a substrate component (A) whose solubility in the developer changes due to the action of acid, and a fluorinated additive component (F) that exhibits decomposition properties in alkaline developers. The above-mentioned fluorinated additive component (F) contains a fluoropolymer component (F1), which has a structural unit (f1) containing a base-dissociable group and a structural unit (f2) containing a group represented by the following general formula (f2-r-1).

[0330]

[0331] In equation (f2-r-1), Rf 21 Each group can be independently a hydrogen atom, alkyl group, alkoxy group, hydroxy group, hydroxyalkyl group, or cyano group. n" is an integer from 0 to 2. * represents a bonding bond.

[0332] The above structural unit (f1) includes the structural unit shown in the following general formula (f1-1) or the structural unit shown in the following general formula (f1-2).

[0333]

[0334] In formulas (f1-1) and (f1-2), R is independently a hydrogen atom, an alkyl group with 1 to 5 carbon atoms, or a haloalkyl group with 1 to 5 carbon atoms. X is a divalent linker without an acid-dissociating site. A aryl It is a divalent aromatic cyclic group that can have substituents. X 01 It is a single-bond or divalent linker. R 2 Each is an organic group containing a fluorine atom.

[0335] Examples of substances that can be cited as coatings, coating solutions, and coating compositions include the following.

[0336] A coating comprising a network of metal oxygen-hydroxyl groups having organic ligands via metal carbon bonds and / or metal carboxylate bonds.

[0337] Compositions based on inorganic oxygen / hydroxyl groups.

[0338] A coating solution comprising an organic solvent, a first organometallic composition, and a hydrolyzable metal compound, wherein the first organometallic composition is of formula [formula missing]. (Here, 0 < z ≤ 2 and 0 < (z + x) ≤ 4), Equation R' n SnX 4-n(Here, n = 1 or 2), or a mixture thereof, where R and R' are independently hydrocarbon groups having 1 to 31 carbon atoms, and X is a ligand having a hydrolytic bond to Sn or a combination thereof; the hydrolytic metal compound is of formula MX' v (Here, M is a metal selected from groups 2 to 16 of the periodic table, v is a number from 2 to 6, and X' is a ligand of an MX bond with hydrolytic properties or a combination thereof.)

[0339] A coating solution comprising an organic solvent and the formula RSnO （3 / 2-x / 2） (OH) x The coating solution of the first organometallic compound shown in the formula (where 0 < x < 3) contains about 0.0025 M to about 1.5 M of tin, and R is an alkyl or cycloalkyl group having 3 to 31 carbon atoms, wherein the alkyl or cycloalkyl group is bonded to tin at a secondary or tertiary carbon atom.

[0340] An aqueous solution of an inorganic pattern-forming precursor comprises water, a metal low oxide cation, a polyatomic inorganic anion, and a mixture of radiation-sensitive ligands containing peroxide groups.

[0341] Irradiation with light or electron beams is performed, for example, by a mask (photomask) used to form a prescribed pattern. Examples include i-rays, KrF excimer lasers, ArF excimer lasers, EUV (ultra-ultraviolet) or EB (electron beam). The resist underlayer film formation composition of the present invention is preferably suitable for EB (electron beam) or EUV (ultra-ultraviolet: 13.5 nm) irradiation, and more preferably suitable for EUV (ultra-ultraviolet) exposure.

[0342] There are no particular restrictions on the irradiation energy of the electron beam and the amount of light exposure.

[0343] It can also be baked after exposure to light or electron beams and before development (PEB: Post Exposure Bake).

[0344] There are no particular limitations on the baking temperature, but it is preferably 60°C to 150°C, more preferably 70°C to 120°C, and particularly preferably 75°C to 110°C.

[0345] There are no particular restrictions on the baking time, but it is preferred to be 1 second to 10 minutes, more preferably 10 seconds to 5 minutes, and particularly preferably 30 seconds to 3 minutes.

[0346] For example, an alkaline developer can be used for development.

[0347] Examples of developing temperatures include 5°C to 50°C.

[0348] Examples of development times include 10 seconds to 300 seconds.

[0349] As an alkaline developer, aqueous solutions of inorganic bases such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and ammonia, primary amines such as ethylamine and n-propylamine, secondary amines such as diethylamine and di-n-butylamine, tertiary amines such as triethylamine and methyldiethylamine, alkanolamines such as dimethylethanolamine and triethanolamine, quaternary ammonium salts such as tetramethylammonium hydroxide and tetraethylammonium hydroxide, and cyclic amines such as pyrrole and piperidine can be used. Furthermore, appropriate amounts of alcohols such as isopropanol and nonionic surfactants can be added to the above-mentioned alkaline aqueous solutions. Among these, aqueous solutions of quaternary ammonium salts are preferred, and aqueous solutions of tetramethylammonium hydroxide and choline are more preferred. Furthermore, surfactants can be added to these developers. Alternatively, development can be performed using organic solvents such as butyl acetate instead of an alkaline developer, resulting in partial development without increasing the alkaline dissolution rate of the photoresist.

[0350] Next, using the formed resist pattern as a mask, the underlying resist film is etched. Etching can be dry etching or wet etching, but dry etching is preferred.

[0351] When the aforementioned inorganic film is formed on the surface of the semiconductor substrate, the surface of the inorganic film is exposed; when the aforementioned inorganic film is not formed on the surface of the semiconductor substrate, the surface of the semiconductor substrate is exposed. Then, by processing the semiconductor substrate using a known method (such as dry etching), a semiconductor device can be manufactured.

[0352] Example

[0353] The following examples illustrate the content of the present invention in detail, but the present invention is not limited to these examples.

[0354] The weight-average molecular weights of the polymers shown in Synthetic Examples 1-7 and Comparative Synthetic Examples 1-3 in this specification are determined using gel permeation chromatography (hereinafter referred to as GPC). The determination was performed using... The GPC apparatus manufactured by (Company Name) and the measurement conditions are as follows.

[0355] ·GPC column: TSKgel Super-MultiporeHZ-N (2 columns)

[0356] Column temperature: 40℃

[0357] Solvent: Tetrahydrofuran (THF)

[0358] • Flow rate: 0.35 ml / minute

[0359] Standard sample: polystyrene ( (Plant)

[0360] <Synthesis example 1>

[0361] Under nitrogen atmosphere, 15.00 g of 2,2'-biphenol (manufactured by Tokyo Chemical Industry Co., Ltd.), 8.55 g of 1-benzaldehyde (manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.77 g of methanesulfonic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) were added to a reaction vessel, followed by the addition of 24.32 g of propylene glycol monomethyl ether acetate. After purging the reaction vessel with nitrogen, the reaction was carried out at 140°C for 3 hours. After cooling, reprecipitation was performed in methanol. The resulting precipitate was filtered and dried at 60°C for 12 hours using a vacuum dryer to obtain polymer 1 as the target. GPC analysis showed that polymer 1 had a weight-average molecular weight of 4,600 and a dispersion of 2.3, calculated using standard polystyrene. The structure present in polymer 1 is shown in the following formula.

[0362]

[0363] <Synthesis example 2>

[0364] Under nitrogen atmosphere, 15.00 g of 2,2'-biphenyl (manufactured by Tokyo Chemical Industry Co., Ltd.) and 1-naphthaldehyde ( 12.58 g of propylene glycol monomethyl ether acetate (PPG) and 1.94 g of methanesulfonic acid (Tokyo Chemical Industry Co., Ltd.) were added, and 29.52 g of propylene glycol monomethyl ether acetate was further added. After purging the reaction vessel with nitrogen, the reaction was carried out at 140°C for 3 hours. After cooling, the product was reprecipitated in methanol. The resulting precipitate was filtered and dried at 60°C for 12 hours using a vacuum dryer to obtain polymer 2 as the target. GPC analysis showed that the weight-average molecular weight of polymer 2, converted from standard polystyrene, was 51,500, and the dispersity was 29.6. The structure present in polymer 2 is shown in the following formula.

[0365]

[0366] <Synthesis Example 3>

[0367] Under nitrogen atmosphere, 25.00 g of 2,2'-biphenyl (manufactured by Tokyo Chemical Industry Co., Ltd.) and 1-naphthaldehyde ( 10.48 g of 1-pyrenecarbaldehyde (manufactured by Tokyo Chemical Industry Co., Ltd.), 15.46 g of methanesulfonic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), and 3.87 g of propylene glycol monomethyl ether (54.81 g) were added. After purging the reaction vessel with nitrogen, the reaction was carried out at 120°C for 24 hours. After cooling, the product was reprecipitated in methanol. The resulting precipitate was filtered and dried at 50°C for 10 hours using a vacuum dryer to obtain polymer 3 as the target. GPC analysis showed that the weight-average molecular weight of polymer 3, converted from standard polystyrene, was 5,000, and the dispersion was 4.8. The structure present in polymer 3 is shown in the following formula.

[0368]

[0369] <Synthesis example 4>

[0370] 4.00 g of 1,3,5-tris(2,3-epoxypropyl)isocyanuric acid (product name: TEPIC-SS, manufactured by Nissan Chemical Co., Ltd.) and 3,7-dihydroxy-2-naphthoic acid ( (manufactured by (strain)) 8.19g, and ethyltriphenyl bromide 0.36 g of propylene glycol monomethyl ether (manufactured by Hokuko Chemical Industry Co., Ltd.) was dissolved in 29.29 g of propylene glycol monomethyl ether in a reaction vessel. After purging the reaction vessel with nitrogen, the reaction was carried out at 140°C for 24 hours to obtain a solution containing polymer 4. GPC analysis showed that the weight-average molecular weight of polymer 4, converted from standard polystyrene, was 1,000, and the dispersity was 4.8. The structure present in polymer 4 is shown in the following formula.

[0371]

[0372] <Synthesis example 5>

[0373] Under nitrogen atmosphere, 6.00 g of anhydrous phloroglucinol (manufactured by Tokyo Chemical Industry Co., Ltd.), 17.15 g of 4-tert-butoxystyrene (manufactured by Tokyo Chemical Industry Co., Ltd.), and 2.74 g of methanesulfonic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) were added to a reaction vessel, followed by 23.15 g of propylene glycol monomethyl ether. The reaction was carried out at 140 °C for 24 hours. After cooling, the product was reprecipitated in heptane. The resulting precipitate was filtered and dried at 60 °C for 12 hours using a vacuum dryer to obtain polymer 5 as the target. GPC analysis showed that the weight-average molecular weight of polymer 5, converted from standard polystyrene, was 1,300, and the dispersity was 1.6. The structure present in polymer 5 is shown in the following formula.

[0374]

[0375] <Synthesis Example 6>

[0376] Under nitrogen atmosphere, 6.00 g of anhydrous phloroglucinol (manufactured by Tokyo Chemical Industry Co., Ltd.) and 2-tert-butoxy-6-vinylnaphthalene (product name: ...) were added to the reaction vessel. 32.30 g of propylene glycol monomethyl ether and 6.86 g of methanesulfonic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) were further added, and the mixture was reacted at 140°C for 24 hours. After cooling, the mixture was reprecipitated in hexane, and the resulting precipitate was filtered and dried at 60°C for 12 hours using a vacuum dryer to obtain polymer 6 as the target. GPC analysis showed that the weight-average molecular weight of polymer 6, converted from standard polystyrene, was 970, and the dispersity was 1.7. The structure present in polymer 6 is shown in the following formula.

[0377]

[0378] <Synthesis Example 7>

[0379] 2-tert-butoxy-6-vinylnaphthalene (product name: 8.00 g of propylene glycol monomethyl ether acetate (hereinafter referred to as PGMEA) and 0.48 g of azobisisobutyronitrile (PTB) were dissolved in 19.79 g of propylene glycol monomethyl ether acetate (hereinafter referred to as PGMEA in this specification). This solution was then added to 14.13 g of PGMEA in a reaction vessel heated and maintained at 140°C, and reacted for 3 hours to obtain a polymer solution. After cooling, the solution was reprecipitated in ultrapure water / methanol. The resulting precipitate was filtered and dried at 60°C for 12 hours using a vacuum dryer to obtain the polymer. Further, 38.51 g of propylene glycol monomethyl ether acetate and 2.22 g of methanesulfonic acid (PTA) were added to 7.41 g of the obtained polymer, and the reaction was carried out at 80°C for 7 hours. After cooling, the solution was reprecipitated in ultrapure water / methanol. The resulting precipitate was filtered and dried at 40°C for 24 hours using a vacuum dryer to obtain the target polymer 7. GPC analysis revealed that polymer 7 had a weight-average molecular weight of 8,300 and a dispersion of 2.3, calculated using standard polystyrene. The structures present in polymer 7 are shown in the following formula.

[0380]

[0381] <Comparative Synthesis Example 1>

[0382] 100.00 g of monoallyl diglycidyl isocyanuric acid (manufactured by Shikoku Chemical Industry Co., Ltd.), 66.4 g of 5,5-diethylbarbituric acid, and 4.1 g of benzyltriethylammonium chloride were dissolved in 682.00 g of propylene glycol monomethyl ether in a reaction vessel. After purging the reaction vessel with nitrogen, the reaction was carried out at 130°C for 24 hours to obtain a solution containing comparative polymer 1. GPC analysis showed that the weight-average molecular weight of comparative polymer 1, converted from standard polystyrene, was 6,800, and the dispersity was 4.8. The structure present in comparative polymer 1 is shown in the following formula.

[0383]

[0384] <Comparative Synthesis Example 2>

[0385] 6.00 g of styrene (manufactured by Tokyo Chemical Industry Co., Ltd.), 2.50 g of 2-hydroxyethyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.43 g of azobisisobutyronitrile (manufactured by Tokyo Chemical Industry Co., Ltd.) were dissolved in 0.82 g of PGMEA. This solution was then added to 14.87 g of PGMEA in a reaction vessel heated and maintained at 140°C, and allowed to react for 24 hours to obtain a solution containing comparative polymer 2. GPC analysis showed that the weight-average molecular weight of comparative polymer 2, converted from standard polystyrene, was 7,700, and the dispersity was 2.6. The structure present in comparative polymer 2 is shown in the following formula.

[0386]

[0387] <Comparative Synthesis Example 3>

[0388] 5.00 g of 4-hydroxyphenyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.) and 0.38 g of azobisisobutyronitrile (manufactured by Tokyo Chemical Industry Co., Ltd.) were dissolved in 20.82 g of PGMEA, and then added to 12.54 g of PGMEA in a reaction vessel heated and maintained at 80°C. The reaction was allowed to proceed for 24 hours, yielding a solution containing comparative polymer 3. GPC analysis showed that the comparative polymer 3 had a weight-average molecular weight of 3,900 converted from standard polystyrene and a dispersion of 1.8. The structure present in comparative polymer 3 is shown in the following formula.

[0389]

[0390] (Example and Comparative Examples)

[0391] The compounds or polymers obtained in the above synthetic examples 1 to 7, comparative synthetic examples 1 to 3, and the following polymers, crosslinking agents, curing catalysts, and solvents were mixed in the ratios shown in Table 1-1 or Table 1-2 and filtered through a 0.1 μm fluoropolymer filter to prepare compositions for forming a resist underlayer film.

[0392] Regarding polymers, the substances described below are used. Abbreviations from Tables 1-1 and 1-2 are also shown.

[0393] • PSF-2808: Cresol phenolic resin (Product name: PSF-2808, manufactured by Chung-Ei Chemical Co., Ltd.)

[0394] ·TA: Tannic acid (product name: (Made by Fuji Chemical Industry Co., Ltd.)

[0395] • TEP-TPA: Polyphenol Resin-1 (Product Name: TEP-TPA, manufactured by Honshu Chemical Co., Ltd.)

[0396] NF7177C: Polyphenol Resin-2 (Product Name: NeoFARIT 7177C) (Company name)

[0397] NFV002-EA2: Polyphenol Resin-3 (Product Name: NeoFARIT V002-EA2) (Company name)

[0398] NFV003: Polyphenol Resin-4 (Product Name: NeoFARIT V003) (Company name)

[0399] • VP-8000: Phenolic resin (Product name: VP-8000, manufactured by Nippon Soda Co., Ltd.)

[0400] Other abbreviations in Tables 1-1 and 1-2 are as follows.

[0401] ·PL-LI: Tetramethoxymethylglycourea

[0402] ·PGME-PL: imidazo[4,5-d]imidazo-2,5(1H,3H)-dione, tetrahydro-1,3,4,6-tetrakis[(2-methoxy-1-methylethoxy)methyl]-(Imidazo[4,5-d]imidazole-2,5(1H,3H)-dione, tetrahydro-1,3,4,6-tetrakis[(2-methoxy-1-methylethoxy)methyl]-)

[0403] ·TMOM-BP: 3,3',5,5'-Tetra(methoxymethyl)-[1,1'-biphenyl]-4,4'-diol

[0404] PyPSA: Pyridine - p-hydroxybenzenesulfonic acid

[0405] R-30N: Surfactant

[0406] ·PGMEA: Propylene glycol monomethyl ether acetate

[0407] ·PGME: Propylene Glycol Monomethyl Ether

[0408] The amounts added are expressed in parts by mass, and the solvents are expressed as a composition ratio.

[0409] [Table 1-1]

[0410] [Table 1-2]

[0411] (Dissolution test of photoresist solvent)

[0412] The photoresist underlayer film forming compositions of Examples 1-14 and Comparative Examples 1-4 were respectively coated onto silicon wafers using a spin coater. The silicon wafers were baked on a hot plate at 205°C for 60 seconds to obtain films with a thickness of 5 nm. These photoresist underlayer films were then immersed in a mixed solution of propylene glycol monomethyl ether / propylene glycol monomethyl ether acetate = 70 / 30 (mass ratio) as the solvent used as the photoresist, and the film thickness was varied to 5 nm. The following conditions will be set to "Good" and will be greater than 5. The condition is set as "poor", and the results are shown in Table 2.

[0413] [Table 2]

[0414] (Determination of the atomic percentage (atom%) of oxygen in phenolic hydroxyl groups in the lower layer of the resist film)

[0415] The resist underlayer film formation composition was spin-coated onto silicon wafers. The silicon wafers were then baked on a hot plate at 205°C for 60 seconds to obtain a resist underlayer film with a thickness of 5 nm. The silicon wafers with the resist underlayer film were cut into pieces approximately 0.5 × 1 cm in size and dried under reduced pressure for at least 20 hours. Then, together with 3 ml of trifluoroacetic anhydride, they were sealed in a 6.0 × 7.5 cm weighing bottle, and the hydrogen atoms of the phenolic hydroxyl groups were replaced with trifluoroacetyl groups by gas-phase chemical modification at 25°C. The reaction time was set based on the time required for each composition to reach reaction equilibrium. Unreacted trifluoroacetic anhydride and trifluoroacetic acid generated as a byproduct were further removed by reduced pressure drying for at least 20 hours. Then, the number of atoms constituting the film (excluding hydrogen) was determined using X-ray photoelectron spectroscopy (Quanterar SXM) with AlKa rays as the radiation source. The atomic percentage (R) of the oxygen atoms in the phenolic hydroxyl groups in the resist underlayer film was then calculated using the following formula. OH [atom%]). The atomic percentage of oxygen in the phenolic hydroxyl groups in the resist underlayer film of Examples 1-5, 7-14, and Comparative Examples 1-4 is shown in Table 4. It was confirmed that the atomic percentage of oxygen in the phenolic hydroxyl groups in Examples 1-5 and 7-14 was higher than that in Comparative Examples 1-4.

[0416]

[0417] F: Number of fluorine atoms

[0418] A: The total number of atoms (excluding hydrogen atoms).

[0419] [Table 3]

[0420] (Evaluation of resist pattern formation)

[0421] [Experiment on the formation of resist patterns using an electron beam exposure device]

[0422] The resist underlayer films of Examples 1-14 and Comparative Examples 1-4 were respectively coated onto silicon wafers using a spin coater. The silicon wafers were baked on a hot plate at 205°C for 60 seconds to obtain a resist underlayer film with a thickness of 5 nm. An EUV positive resist solution was spin-coated onto this resist underlayer film, and the film was heated at 130°C for 60 seconds to form an EUV resist film. The resist film was exposed using an electron beam lithography apparatus (ELS-G130) under specified conditions. After exposure, a 60-second photobake (PEB) was performed at 100°C, followed by cooling to room temperature on a cooling plate. Puddle developing was then performed for 30 seconds using a 2.38% tetramethylammonium hydroxide aqueous solution (manufactured by Tokyo Ohka Kogyo Co., Ltd., trade name NMD-3) as the photoresist developer. Resist patterns with aperture sizes of 16 nm to 26 nm were formed. The length of the resist pattern was measured using a scanning electron microscope. (Creation, CG4100).

[0423] Regarding the photoresist pattern obtained through this operation, it was confirmed whether a 23 nm contact hole (C / H) could be formed. In all cases from Examples 1 to 14, the formation of a 23 nm C / H pattern was confirmed. Furthermore, the charge amount at which the 23 nm contact hole was formed was set as the optimal irradiation energy, and the irradiation energy (μC / cm) for Comparative Example 1 was set to 1.00. 2 The results are shown in Table 4. It was confirmed that the optimal irradiation energy of Examples 1-14 was reduced compared to Comparative Examples 1-4.

[0424] [Table 4]

[0425] Industrial availability

[0426] The resist underlayer film forming composition of the present invention can provide a resist underlayer film forming composition for forming a resist underlayer film capable of forming a desired resist pattern, and 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 composition for forming a resist underlayer film, comprising a compound (A) and a solvent (B), said compound (A) containing an aromatic hydrocarbon ring with a phenolic hydroxyl group bonded to it. The atomic percentage of oxygen in the phenolic hydroxyl groups of the cured film of the composition is 2.00% or more.

2. The composition for forming a resist underlayer film according to claim 1, wherein the compound (A) comprises at least one of phenolic resin, naphthol resin, biphenol resin, polyhydroxystyrene resin, and polyhydroxyvinylnaphthalene resin.

3. The composition for forming a resist underlayer film according to claim 1, wherein the compound (A) is a low molecular weight compound (A-1) containing two or more phenolic hydroxyl groups and having a molecular weight of 5000 or less.

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

5. The composition for forming a resist underlayer according to claim 1, wherein it is a composition for forming a resist underlayer for EUV or electron beam lithography.

6. A resist underlayer film, which is a cured product of the resist underlayer film forming composition according to any one of claims 1 to 5.

7. The photoresist underlayer film according to claim 6, wherein the atomic percentage of oxygen in the phenolic hydroxyl groups is 2.00% or more.

8. The resist lower layer film according to claim 6, wherein the film thickness is 2 nm or more and 20 nm or less.

9. A laminated body comprising: Semiconductor substrates, and The resist underlayer film as described in claim 6.

10. A method for manufacturing a semiconductor device, comprising the following steps: The process of forming a photoresist underlayer film on a semiconductor substrate using the photoresist underlayer film forming composition according to any one of claims 1 to 5; and The process of forming a resist film on the lower resist film.

11. A pattern forming method, comprising the following steps: The process of forming a photoresist underlayer film on a semiconductor substrate using the photoresist underlayer film forming composition according to any one of claims 1 to 5; The process of forming a resist film on the lower resist film; The process of irradiating the resist film with light or an electron beam, and then developing the resist film to obtain a resist pattern; as well as The process of using the resist pattern as a mask to etch the underlying resist film.

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