Composition for resist underlayer film formation

Abstract

A composition for forming an underlayer film of a resist, which is a composition for forming an underlayer film of a resist comprising a resin (A) and a solvent (B), the resin (A) being a polymer comprising a structural unit represented by the following formula (1) or a structural unit represented by the following formula (2). (In formula (1), R 1 represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R 2 represents a hydrogen atom, a methyl group or an ethyl group, and p is an average addition mole number and is 2 to 20. In formula (2), Q represents a 2-valent group not having a sulfur atom, and q is an average addition mole number and is 1 to 20.)

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 pattern, developing the film, and then etching the substrate using the resulting photoresist pattern as a protective film. This process creates micro-unfolds on the substrate surface corresponding to the photoresist pattern. In recent years, with the advancement of high integration in semiconductor devices, the active light used has expanded beyond previously used i-rays (365 nm wavelength), KrF excimer lasers (248 nm wavelength), and ArF excimer lasers (193 nm wavelength). The practical application of EUV light (13.5 nm wavelength) or EB (electron beam) has been investigated in cutting-edge microfabrication. However, this has led to a significant problem of poor photoresist pattern formation caused by influences from the semiconductor substrate. Therefore, to address this issue, methods for setting a photoresist underlayer between the photoresist and the semiconductor substrate have been extensively studied.

[0003] As a composition for forming a resist underlayer film, a composition for forming a resist underlayer film has been proposed, comprising a compound (A) of formula (1) (in formula (1), A represents an organic group containing an aliphatic ring, an aromatic ring or a heterocyclic ring) dissolved in a solvent, a compound (B) having two functional groups that are reactive with an epoxy group, and a compound (C) having one functional group that is reactive with an epoxy group (see Patent Document 1).

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: International Publication No. 2022 / 075339 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] As required properties of the lower layer of the resist film, examples include not mixing with the resist film formed on the upper layer (insoluble in resist solvent) and improving resist sensitivity.

[0009] 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 that can improve the sensitivity of the photoresist, and a method for manufacturing a photoresist underlayer film, a stack, a semiconductor device, and a patterning method using the photoresist underlayer film forming composition.

[0010] Methods for solving problems

[0011] 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 main points.

[0012] That is, the present invention includes the following solutions.

[0013] [1] A composition for forming a photoresist underlayer film, comprising a resin (A) and a solvent (B), The resin (A) described above is a polymer containing the structural unit shown in formula (1) or the structural unit shown in formula (2).

[0014]

[0015] (In equation (1), R) 1 R represents an alkyl group having 1 to 3 hydrogen atoms or carbon atoms. 2 It represents a hydrogen atom, a methyl group, or an ethyl group, and p is the average number of moles of addition, which is 2 to 20.

[0016] In equation (2), Q represents a divalent group without sulfur atoms, and q is the average number of moles added, ranging from 1 to 20.

[0017] [2] According to the composition for forming a resist underlayer film as described in [1], Q in the above formula (2) is represented by the following formula (2-1) or formula (2-2).

[0018]

[0019] (In equation (2-1), Q) 1 The group represents alkylene, alkenylene, ynylene, phenylene, naphthylene, or anthracene, wherein the aforementioned phenylene, naphthylene, and anthracene can each be independently substituted by a group selected from alkyl, halogen, alkoxy, nitro, cyano, and hydroxyl groups having 1 to 6 carbon atoms. n1 and n2 each independently represent 0 or 1.

[0020] In equation (2-2), X 1 Z represents any of the groups shown in formulas (2-2-1) to (2-2-3) below. 1 and Z 2 Each can independently represent a single bond or a group represented by the following formula (2-2-4).

[0021] (This represents a bonding bond.)

[0022] (In equations (2-2-1) to (2-2-3), R) 11 and R 12 Each of these groups independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, a benzyl group, or a phenyl group. The benzyl and phenyl groups can be substituted with groups selected from alkyl groups having 1 to 6 carbon atoms, halogen groups, alkoxy groups having 1 to 6 carbon atoms, nitro groups, cyano groups, hydroxyl groups, and alkylthio groups having 1 to 6 carbon atoms. Furthermore, R... 11 With R 12 They can combine with each other to form rings with 3 to 6 carbon atoms.

[0023] R 13 The group represents an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, a benzyl group, or a phenyl group. Furthermore, the benzyl group and the phenyl group can each be independently substituted by a group selected from alkyl groups having 1 to 6 carbon atoms, halogen groups, alkoxy groups having 1 to 6 carbon atoms, nitro groups, cyano groups, and hydroxyl groups.

[0024] This represents a bonding bond. 1 represents the bonding bond with the carbon atom in formula (2-2). 2 represents the bonding bond with the nitrogen atom in formula (2-2).

[0025] In equation (2-2-4), m represents an integer from 1 to 4. n represents an integer from 0 to 4. p1 and p2 each independently represent 0 or 1. 3 represents the bonding bond that binds to the nitrogen atom in equation (2-2). 4 represents a bonding bond.

[0026] [3] According to the composition for forming a resist underlayer film as described in [1], the resin (A) is a polymer (1) comprising the structural unit shown in formula (1) above. The mass percentage of the structural unit shown in formula (1) in the polymer (1) is 50% by mass or more.

[0027] [4] According to the composition for forming a resist underlayer film as described in [1] or [2], the resin (A) is a polymer (2) comprising the structural unit shown in formula (2) above. The mass percentage of the structural unit shown in formula (2) in the polymer (2) is 50% by mass or more.

[0028] [5] The composition for forming a resist underlayer film according to any one of [1] to [4], wherein the solvent (B) comprises at least one selected from carboxylic acids having hydroxyl groups, straight-chain or cyclic alkyl ketones, cyclic lactones, monoalkylene glycol monoalkyl ethers, monocarboxylic acid esters of monoalkylene glycol monoalkyl ethers and alkoxycarboxylic acid esters of monoalkylene glycol monoalkyl ethers.

[0029] [6] The composition for forming a resist underlayer film according to any one of [1] to [5] further comprises a crosslinking agent (C).

[0030] [7] In the composition for forming a resist underlayer film according to [6], the crosslinking agent (C) is selected from at least one of amino plastic crosslinking agents and phenolic plastic crosslinking agents.

[0031] [8] The composition for forming a resist underlayer film according to any one of [1] to [7] further comprises a curing catalyst (D).

[0032] [9] A resist underlayer film, which is a cured product of the resist underlayer film forming composition described in any one of [1] to [8].

[0033]

[10] A laminated body having

[0034] Semiconductor substrates, and

[0035] [9] The lower layer film of the resist.

[0036]

[11] 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 [1] to [8]; and The process of forming a resist film on the lower resist film mentioned above.

[0037]

[12] 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 according to any one of [1] to [8]; The process of forming a resist film on the aforementioned 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; and The process of using the above-mentioned resist pattern as a mask and etching the above-mentioned resist underlayer film.

[0038] The effects of the invention

[0039] According to the present invention, a composition for forming a photoresist underlayer film that can improve the sensitivity of the photoresist 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

[0040] (Composition for forming the lower layer film of the resist)

[0041] The composition for forming a resist underlayer film of the present invention comprises a resin (A) and a solvent (B).

[0042] The composition for forming the lower layer film of the resist may include a crosslinking agent (C), a curing catalyst (D), etc.

[0043] Resin (A) has ethylene glycol groups.

[0044] By including a resin (A) having ethylene glycol groups in the composition for forming the resist underlayer, a resist pattern with improved sensitivity can be formed on the resist underlayer film formed by the composition for forming the resist underlayer.

[0045] <Resin (A)>

[0046] Resin (A) is a polymer containing structural units shown in formula (1) or formula (2).

[0047]

[0048] (In equation (1), R) 1 R represents an alkyl group having 1 to 3 hydrogen atoms or carbon atoms. 2 It represents a hydrogen atom, a methyl group, or an ethyl group, and p is the average number of moles of addition, which is 2 to 20.

[0049] In equation (2), Q represents a divalent group without sulfur atoms, and q is the average number of moles added, ranging from 1 to 20.

[0050] p can be 2 to 20, 2 to 10, or 2 to 7.

[0051] q can be 1 to 20, 1 to 15, or 1 to 10.

[0052] As R 1 The preferred atoms are hydrogen atoms and methyl groups.

[0053] Q will be described later.

[0054] <<Polymers containing the structural units shown in formula (1)>>

[0055] The polymer containing the structural unit shown in formula (1) (hereinafter, sometimes referred to as "polymer (1)") is, for example, a vinyl polymer.

[0056] Vinyl polymers are polymers formed by polymerizing unsaturated bonds in compounds containing groups with polymerizable unsaturated bonds. Vinyl polymers can be homopolymers or copolymers.

[0057] Examples of groups having polymerizable unsaturated bonds include (meth)acryloyl, (meth)acrylamido, vinylaryl (e.g., styryl), vinyloxy, allyl, etc.

[0058] As a unit for obtaining the structural unit shown in formula (1), examples can be given, for example, the unit shown in formula (1A) below.

[0059]

[0060] (In equation (1A), R) 1 R 2 And p are respectively related to R in equation (1) 1 R 2 (Same meaning as p.)

[0061] Examples of monomers represented by formula (1A) include, for example, polyethylene glycol mono(meth)acrylate.

[0062] The monomer shown in formula (1A) can be a commercially available product. Examples of commercially available products include Bream PE90, PE-200, and PE-350 (Nippon Oil (manufactured)).

[0063] The polymer (1) may have structural units other than those shown in formula (1). Examples of such structural units include those shown in formula (B-10), formula (B-11), formula (B-12), and formula (B-13).

[0064] It should be noted that the structural unit shown in equation (B-11), equation (B-12), and equation (B-13) are different from the structural unit shown in equation (1) and equation (B-10).

[0065]

[0066] (In equation (B-10), R) 2 Indicates an alkyl group having 1 to 10 hydrogen or carbon atoms. L 1 Indicates a single bond or linker. L 2 This represents a monovalent group with polymerizable multiple bonds.

[0067]

[0068] (In equation (B-11), R) 2 L represents an alkyl group having 1 to 10 hydrogen atoms or carbon atoms. 53 A monovalent base representing carbon atoms from 1 to 20.

[0069] In equation (B-12), R 2 Ar represents a benzene ring or a naphthalene ring, and L represents a hydrogen atom or an alkyl group with 1 to 10 carbon atoms. 54 This indicates a hydroxyl, cyano, nitro, or amino group (-NH2). L 55 This indicates a halogen atom, an alkyl group with 1 to 6 carbon atoms, or an alkoxy group with 1 to 6 carbon atoms. m1 represents an integer from 0 to 3. m2 represents an integer from 0 to 5. The sum of m1 and m2 is 0 to 5. When m1 is 2 or 3, multiple L... 54 They can be the same or different. When m² is 2 to 5, multiple L... 55 They can be the same or different.

[0070] In equation (B-13), R 2 L represents an alkyl group having 1 to 10 hydrogen atoms or carbon atoms. 56 This refers to a monovalent organogroup selected from alkyl groups having 1 to 10 carbon atoms and aryl groups having 6 to 40 carbon atoms, wherein at least one hydrogen atom of the aforementioned alkyl or aryl group may be substituted by a hydroxyl group or an alkoxy group having 1 to 6 carbon atoms.

[0071] R in equations (B-10) to (B-13) 2 Each of these is preferably composed of hydrogen atoms or methyl groups.

[0072] In L 1 In the case of a linker, there is no particular limitation on the number of carbon atoms that serve as the linker, and examples include 1 to 10.

[0073] In L 1 In the case of a linker, examples of linkers include linkers having a structure obtained by reacting an epoxy group with a nucleophilic functional group, and linkers having a structure obtained by reacting an isocyanate group with a nucleophilic functional group.

[0074] As L 1 Examples of such connections include the following bases (L1-1) to (L1-11).

[0075]

[0076] (in the formula, 1 represents R in equation (B-10) 2 The carbon atoms are bonded together by a bonding bond. 2 represents L in equation (B-10) 2 The bonding bond.

[0077] L 2 It is a monovalent base with polymerizable multiple bonds. This monovalent base can be the polymerizable multiple bond itself.

[0078] There is no particular restriction on the number of carbon atoms in the monovalent group; for example, it can be 1 to 20 or 1 to 10.

[0079] Polymerizable multiple bonds are, for example, one or more polymerizable multiple bonds selected from carbon-carbon double bonds, carbon-carbon triple bonds, carbon-nitrogen double bonds, and carbon-nitrogen triple bonds.

[0080] As L 2 Examples of monovalent groups with polymerizable multiple bonds in the group include (meth)acryloyl, (meth)acrylamido, vinylaryl (e.g., styryl), vinyloxy, allyl, etc.

[0081] In addition, L 2 Examples of such examples include the monovalent bases shown in equations (L2-1) to (L2-81).

[0082]

[0083] ( (This represents a bonding bond.)

[0084] As in equation (B-10) -L 1 -L 2 The radical can be exemplified by, for example, the radical shown in the following formula.

[0085]

[0086] (where R is in the formula) a It represents a hydrogen atom or a methyl group. (This represents a bonding bond.)

[0087] L in formula (B-11)53 The monovalent group having 1 to 20 carbon atoms represents, for example, a monovalent organogroup selected from alkyl groups having 1 to 10 carbon atoms and aryl groups having 6 to 40 carbon atoms, wherein at least one hydrogen atom of the alkyl group and the aryl group can be replaced by a hydroxyl group. Furthermore, the alkyl group can have an oxygen atom inserted between carbon atoms.

[0088] In addition, as L 53 The monovalent group having 1 to 20 carbon atoms can be exemplified by, for example, the group shown in the following formula (B-11-1).

[0089]

[0090] (In equation (B-11-1), L) 3a This indicates an alkyl group with 1 to 6 carbon atoms that can be substituted, or an aromatic hydrocarbon group that can be substituted. X indicates a single bond or a carbonyl group. (This represents a bonding bond.)

[0091] As L 3a Aromatic hydrocarbon groups in the form of phenyl or naphthyl groups can be cited as examples.

[0092] As L 3a The substituents can be alkyl groups having 1 to 6 carbon atoms, such as halogen atoms and hydroxyl groups. There can be one or more substituents. When there are multiple substituents, the substituents can be the same or different.

[0093] As L 3a Substituents in substituted aromatic hydrocarbon groups can include, for example, halogen atoms, hydroxyl groups, and alkyl groups with 1 to 3 carbon atoms that can be replaced by halogen atoms. There can be one or more substituents. When there are multiple substituents, they can be the same or different.

[0094] In L 3a When the alkyl group has 1 to 6 carbon atoms that can be substituted, for example, X represents a carbonyl group.

[0095] As L 55 Halogen atoms in halogen atoms can be exemplified by fluorine, chlorine, bromine, and iodine atoms.

[0096] As L 55 Alkyl groups having 1 to 6 carbon atoms include, for example, methyl, ethyl, n-propyl, isopropyl, cyclopropyl, n-butyl, isobutyl, etc.

[0097] As L 55 Alkoxy groups with 1 to 6 carbon atoms can be exemplified by, for example, methoxy, ethoxy, propoxy, and butoxy.

[0098] m1 represents an integer from 0 to 3, which can be 0, 1, 2, or 3.

[0099] m2 represents an integer from 0 to 5, which can be 0, 1, 2, 3, 4, or 5.

[0100] As L 53 and L 56 Examples of aryl groups with 6 to 40 carbon atoms include phenyl, o-methylphenyl, m-methylphenyl, p-methylphenyl, o-chlorophenyl, m-chlorophenyl, p-chlorophenyl, o-fluorophenyl, p-fluorophenyl, o-methoxyphenyl, p-methoxyphenyl, p-nitrophenyl, p-cyanophenyl, α-naphthyl, β-naphthyl, o-biphenyl, m-biphenyl, p-biphenyl, 1-anthrayl, 2-anthrayl, 9-anthrayl, 1-phenanthyl, 2-phenanthyl, 3-phenanthyl, 4-phenanthyl, and 9-phenanthyl.

[0101] As L 56 Alkoxy groups with 1 to 6 carbon atoms can be exemplified by, for example, methoxy, ethoxy, propoxy, and butoxy.

[0102] Examples of monomers used for the purpose of derivatization (B-11) include the following compounds.

[0103]

[0104] Examples of monomers used for the derivatization (B-12) include the following compounds.

[0105]

[0106] Me represents methyl.

[0107] Examples of monomers used for the purpose of derivatization (B-13) include the following compounds.

[0108]

[0109] There is no particular limitation on the mass ratio of the structural unit represented by formula (1) in polymer (1), but from the viewpoint of better obtaining the effects of the present invention, it is preferably 50% by mass or more.

[0110] Polymer (1) can be obtained, for example, by free radical polymerization.

[0111] Furthermore, as a method for obtaining a polymer (1) having polymerizable multiple bonds, one example is a method of reacting the resulting polymer with (meth)acrylic acid after copolymerizing the monomer shown in formula (1A) with a monomer having epoxy groups and polymerizable unsaturated bonds (e.g., glycidyl methacrylate). In the reaction of the polymer with (meth)acrylic acid, a group containing polymerizable multiple bonds ((meth)acryloyl) is introduced into the side chain of the polymer by reacting the epoxy groups in the polymer with the carboxyl groups in (meth)acrylic acid.

[0112] <<Polymers containing the structural units shown in formula (2)>>

[0113] The polymer (hereinafter, sometimes referred to as "polymer (2)") containing the structural unit shown in formula (2) will be described.

[0114] The polymer (2) comprises the structural unit shown in the following formula (2).

[0115]

[0116] (In formula (2), Q represents a divalent group without sulfur atoms, and q is the average number of moles added, which ranges from 1 to 20.)

[0117] As for Q in equation (2), there are no particular restrictions as long as it does not have sulfur atoms. Examples include divalent groups with 1 to 20 carbon atoms.

[0118] From the viewpoint of achieving the effects of the present invention, Q in formula (2) is preferably represented by formula (2-1) or formula (2-2) below.

[0119]

[0120] (In equation (2-1), Q) 1 The group represents alkylene, alkenylene, ynylene, phenylene, naphthylene, or anthracene, wherein the aforementioned phenylene, naphthylene, and anthracene can each be independently substituted by a group selected from alkyl, halogen, alkoxy, nitro, cyano, and hydroxyl groups having 1 to 6 carbon atoms. n1 and n2 each independently represent 0 or 1.

[0121] In equation (2-2), X 1Z represents any of the groups shown in formulas (2-2-1) to (2-2-3) below. 1 and Z 2 Each can independently represent a single bond or a group represented by the following formula (2-2-4).

[0122] (This represents a bonding bond.)

[0123] (In equations (2-2-1) to (2-2-3), R) 11 and R 12 Each of these groups independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, a benzyl group, or a phenyl group. The benzyl and phenyl groups can be substituted with groups selected from alkyl groups having 1 to 6 carbon atoms, halogen groups, alkoxy groups having 1 to 6 carbon atoms, nitro groups, cyano groups, hydroxyl groups, and alkylthio groups having 1 to 6 carbon atoms. Furthermore, R... 11 With R 12 They can combine with each other to form rings with 3 to 6 carbon atoms.

[0124] R 13 The group represents an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, a benzyl group, or a phenyl group. Furthermore, the benzyl group and the phenyl group can each be independently substituted by a group selected from alkyl groups having 1 to 6 carbon atoms, halogen groups, alkoxy groups having 1 to 6 carbon atoms, nitro groups, cyano groups, and hydroxyl groups.

[0125] This represents a bonding bond. 1 represents the bonding bond with the carbon atom in formula (2-2). 2 represents the bonding bond with the nitrogen atom in formula (2-2).

[0126] In equation (2-2-4), m represents an integer from 1 to 4. n represents an integer from 0 to 4. p1 and p2 each independently represent 0 or 1. 3 represents the bonding bond that binds to the nitrogen atom in equation (2-2). 4 represents a bonding bond.

[0127] Q in equation (2-1) 1 The alkylene group can be exemplified by, for example, alkylene groups having 1 to 15 carbon atoms. Alkylene groups can have a cyclic structure. Examples of cyclic structures include, for example, the cyclohexane ring.

[0128] Q in equation (2-1) 1 Examples of groups represented by formula (2-1) in the case of alkylene groups include, for example, the following groups.

[0129]

[0130] ( (This represents a bonding bond.)

[0131] Q in equation (2-1) 1 Examples of alkenyl groups include alkenyl groups with 2 to 15 carbon atoms. Alkenyl groups can have cyclic structures.

[0132] The number of carbon-carbon double bonds in an alkenyl group can be one or more.

[0133] Q in equation (2-1) 1 Examples of groups represented by formula (2-1) in the case of an alkenyl group include, for example, the following groups.

[0134]

[0135] ( (This represents a bonding bond.)

[0136] Q in equation (2-1) 1 Examples of ynylene groups include those with 2 to 15 carbon atoms. Iynylene groups can have a ring structure.

[0137] The number of carbon-carbon triple bonds in an ynynyl group can be one or more.

[0138] Q as in equation (2-1) 1 Examples of groups represented by formula (2-1) with phenylene or naphthylene groups include, for example, the following groups.

[0139]

[0140] ( (This represents a bonding bond.)

[0141] Examples of groups that can be represented by formula (2-2) include the following groups.

[0142]

[0143] ( (This represents a bonding bond.)

[0144] There is no particular limitation on the mass ratio of the structural unit represented by formula (2) in polymer (2), but from the viewpoint of better obtaining the effects of the present invention, it is preferably 50% by mass or more.

[0145] There are no particular limitations on the synthesis method of polymer (2), and examples include the reaction shown in (I) below.

[0146] (I): The reaction of the diepoxide compound represented by formula (2A) with the compound represented by formula (2-1A) or formula (2-2A).

[0147] For reaction (I), compounds other than those mentioned above can be used.

[0148] In reaction (I), a catalyst that activates the epoxy group can be used, for example.

[0149] Catalysts that activate epoxy groups, such as tetrabutyl bromide, are examples of such catalysts. ethyltriphenylbromide That kind of season Salts, such as quaternary ammonium salts like benzyltriethylammonium chloride. The amount used as a catalyst can be selected from 0.1% to 10% by mass relative to the total mass of the polymer feedstock used in the reaction.

[0150] The optimal conditions for the polymerization reaction can be selected from, for example, a range of 80–160°C and 2–50 hours.

[0151]

[0152] (In equation (2A), q has the same meaning as q in equation (2).

[0153] In equation (2-1A), Q 1 n1 and n2 are respectively related to Q in equation (2-1) 1 n1 and n2 have the same meaning.

[0154] In equation (2-2A), X 1 Z 1 and Z 2 Each with X in equation (2-2) 1 Z 1 and Z 2 The meaning is the same.

[0155] It should be noted that, with Z 1 The combined hydrogen atoms and Z 2 The hydrogen atoms that are bonded are usually active hydrogen atoms. Examples of active hydrogen atoms include hydrogen atoms in a carboxyl group and hydrogen atoms bonded to a nitrogen atom.

[0156] The diepoxide compound shown in formula (2A) is, for example, polyethylene glycol diglycidyl ether. Polyethylene glycol diglycidyl ether can be commercially available. Examples of commercially available products include, for instance, eporite 40E, eporite 100E, eporite 200E, and eporite 400E (manufactured by Kyoei Chemical Co., Ltd.).

[0157] The lower limit of the weight-average molecular weight of resin (A) is, for example, 500, 1,000 or 1,500.

[0158] The upper limit of the weight-average molecular weight of resin (A) is, for example, 50,000, 30,000 or 20,000.

[0159] The content of resin (A) in the composition for forming the lower layer of the resist film is not particularly limited. From the viewpoint of obtaining the effect of the present invention, it is preferably 40% to 95% by mass, more preferably 45% to 90% by mass, and particularly preferably 50% to 85% by mass, relative to the film composition.

[0160] It should be noted that, in this invention, the term "film constituents" refers to the components contained in the composition other than the solvent.

[0161] <Solvent (B)>

[0162] As a solvent (B), there are no particular restrictions; it can be water or an organic solvent.

[0163] Examples of organic solvents include, for example, carboxylic acids having hydroxyl groups, straight-chain or cyclic alkyl ketones, cyclic lactones, alkylene glycol alkyl ethers, and alkylene glycol monoalkyl ether carboxylic esters (monocarboxylic esters of alkylene glycol monoalkyl ethers and alkoxycarboxylic esters of alkylene glycol monoalkyl ethers).

[0164] Examples of carboxylic acids having a hydroxyl group include ethyl lactate, propyl lactate, isopropyl lactate, butyl lactate, isobutyl lactate, ethyl hydroxyacetate, ethyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxypropionate, methyl 2-hydroxy-3-methylbutyrate, etc.

[0165] Examples of linear or cyclic alkyl ketones include, for example, methyl ethyl ketone, cyclopentanone, and cyclohexanone.

[0166] Examples of cyclic lactones include, for instance, γ-butyrolactone.

[0167] Examples of alkylene glycol alkyl ethers include, for example, alkylene glycol monoalkyl ethers and alkylene glycol dialkyl ethers.

[0168] Examples of monoalkylene glycol monoalkyl ethers include, for example, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether (1-methoxy-2-propanol), propylene glycol monoethyl ether (1-ethoxy-2-propanol), methyl isobutyl methanol, and propylene glycol monobutyl ether.

[0169] Examples of alkylene glycol dialkyl ethers include, for example, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol dipropyl ether, propylene glycol dibutyl ether, etc.

[0170] Examples of monoalkylene glycol monoalkyl ether carboxylic esters include, for example, monocarboxylic esters of monoalkylene glycol monoalkyl ethers and alkoxycarboxylic esters of monoalkylene glycol monoalkyl ethers.

[0171] Examples of monocarboxylic acid esters of alkylene glycol monoalkyl ethers include, for example, alkylene glycol monoalkyl ether acetates.

[0172] Examples of alkylene glycol monoalkyl ether acetates include, for example, methyl cellosolve acetate, ethyl cellosolve acetate, propylene glycol monomethyl ether acetate (1-methoxy-2-propanol monoacetate), propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, and ethylene glycol monobutyl ether acetate.

[0173] Examples of alkoxycarboxylic acid esters that are monoalkylene glycol ethers include, for example, 2-methoxyethyl methyl carbonate, 2-ethoxyethyl methyl carbonate, 2-ethoxyethyl ethyl carbonate, and 2-propoxyethyl methyl carbonate.

[0174] Specific examples of other solvents include toluene, xylene, ethyl ethoxylate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, ethyl pyruvate, ethyl formate, methyl formate, ethyl formate, propyl formate, isopropyl formate, butyl formate, isobutyl formate, amyl formate, isoamyl formate, methyl acetate, ethyl acetate, amyl acetate, isoamyl acetate, hexyl acetate, methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, butyl propionate, isobutyl propionate, methyl butyrate, ethyl butyrate, propyl butyrate, isopropyl butyrate, butyl butyrate, isobutyl butyrate, ethyl glycolate, and ethyl glycolate. Esters, methyl 3-methoxy-2-methylpropionate, ethyl methoxyacetate, ethyl ethoxyacetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-methoxybutylacetate, 3-methoxypropylacetate, 3-methyl-3-methoxybutylacetate, 3-methyl-3-methoxybutylpropionate, 3-methyl-3-methoxybutylbutyrate, methyl acetoacetate, methyl propyl ketone, methyl butyl ketone, 2-heptanone, 3-heptanone, 4-heptanone, N,N-dimethylformamide, N-methylacetamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, 4-methyl-2-pentanol, etc.

[0175] Among these solvents (B), monoalkylene glycol monoalkyl ethers and monocarboxylic acid esters of monoalkylene glycol monoalkyl ethers are preferred.

[0176] These solvents (B) can be used alone or in combination of two or more.

[0177] The mass ratio of the organic solvent in solvent (B) is not particularly limited, but is preferably 50% to 100% by mass.

[0178] 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.

[0179] <Crosslinking agent (C)>

[0180] There are no particular restrictions on its use as a crosslinking agent (C).

[0181] The crosslinking agent (C) has a different structure from the resin (A).

[0182] As a crosslinking agent (C), amino plastic crosslinking agents and phenolic plastic crosslinking agents are preferred.

[0183] Amino plastic crosslinking agents are addition condensations of amino compounds such as melamine and guanidine with formaldehyde.

[0184] Phenolic plastic crosslinking agents are addition condensation compounds of compounds with phenolic hydroxyl groups and formaldehyde.

[0185] Examples of crosslinking agents (C) include compounds having two or more of the following structures.

[0186]

[0187] (In the structure, R) 101 It represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an alkoxyalkyl group having 2 to 6 carbon atoms. (This represents a bonding bond.)

[0188] Bonding bonds include, for example, bonds with nitrogen atoms or carbon atoms that form aromatic hydrocarbon rings.

[0189] As R 101 Preferably, it contains hydrogen atoms, methyl, ethyl or groups represented by the following structures.

[0190]

[0191] (In the structure, R) 102 It represents a hydrogen atom, a methyl group, or an ethyl group. (This represents a bonding bond.)

[0192] As a crosslinking agent (C), melamine compounds, guanidine compounds, glycourea compounds, urea compounds, and compounds having phenolic hydroxyl groups are preferred. They can be used alone or in combination of two or more.

[0193] Examples of melamine compounds include, for example, hexamethylolmelamine, hexamethoxymethylmelamine, compounds of hexamethylolmelamine in which 1 to 6 hydroxymethyl groups are methoxymethylated, or mixtures thereof, hexamethoxyethylmelamine, hexaacyloxymethylmelamine, compounds of hexamethylolmelamine in which 1 to 6 hydroxymethyl groups are acyloxymethylated, or mixtures thereof.

[0194] Examples of guanidine compounds include, for example, tetrahydroxymethylguanidine, tetramethoxymethylguanidine, compounds of tetrahydroxymethylguanidine in which 1 to 4 hydroxymethyl groups are methoxymethylated, or mixtures thereof, tetramethoxyethylguanidine, tetraacyloxyguanidine, compounds of tetrahydroxymethylguanidine in which 1 to 4 hydroxymethyl groups are acyloxymethylated, or mixtures thereof.

[0195] Examples of glycourea compounds include, for example, tetrahydroxymethylglycourea, tetramethoxyglycourea, tetramethoxymethylglycourea, compounds of tetrahydroxymethylglycourea in which 1 to 4 hydroxymethyl groups are methoxymethylated, or mixtures thereof, compounds of tetrahydroxymethylglycourea in which 1 to 4 hydroxymethyl groups are acylmethylated, or mixtures thereof.

[0196] In addition, as a glycourea compound, it can be, for example, a glycourea derivative as shown in the following formula (1E).

[0197]

[0198] (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 having 1 to 4 carbon atoms, or a phenyl group.)

[0199] Examples of glycourea derivatives represented by the above formula (1E) include compounds represented by formulas (1E-1) to (1E-6).

[0200]

[0201] The glycourea derivative shown in formula (1E) can be obtained, for example, by reacting the glycourea derivative shown in formula (2E) with at least one compound shown in formula (3d).

[0202]

[0203] (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.)

[0204] (In formula (3d), R1 represents methyl or ethyl.)

[0205] Examples of glycourea derivatives represented by formula (2E) include compounds represented by formulas (2E-1) to (2E-4). Further examples of compounds represented by formula (3d) include compounds represented by formulas (3d-1) and (3d-2).

[0206]

[0207] Examples of urea compounds include tetrahydroxymethylurea, tetramethoxymethylurea, compounds of tetrahydroxymethylurea in which 1 to 4 hydroxymethyl groups are methoxymethylated, or mixtures thereof, and tetramethoxyethylurea.

[0208] Examples of compounds having phenolic hydroxyl groups include, for example, compounds represented by formula (G-1) or formula (G-2) below.

[0209]

[0210] (In equations (G-1) and (G-2), Q) 1It represents a single bond or an m1-valent organic group.

[0211] R 1 and R 4 Each represents an alkyl group having 2 to 10 carbon atoms or an alkyl group having 1 to 10 carbon atoms and an alkoxy group having 2 to 10 carbon atoms.

[0212] R 2 and R 5 Each represents a hydrogen atom or a methyl group.

[0213] R 3 and R 6 Each represents an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 40 carbon atoms.

[0214] 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.

[0215] n5 represents an integer where 1 ≤ n5 ≤ 3, n6 represents an integer where 1 ≤ n6 ≤ 4, n7 represents an integer where 0 ≤ n7 ≤ 3, and n8 represents an integer where 0 ≤ n8 ≤ 3, and n5, n6, n7, and n8 represent integers where 2 ≤ (n5 + n6 + n7 + n8) ≤ 5.

[0216] m1 represents an integer from 2 to 10.

[0217] Furthermore, examples of compounds having phenolic hydroxyl groups include, for example, compounds represented by formula (G-3) or formula (G-4) below.

[0218] The compound represented by formula (G-1) or (G-2) can be obtained by reacting the compound represented by formula (G-3) or (G-4) with an ether compound containing a hydroxyl group or an alcohol having 2 to 10 carbon atoms.

[0219]

[0220] (In equations (G-3) and (G-4), Q) 2 It represents a single bond or an m2 valence organic group.

[0221] R 8 R 9 R 11 and R 12 Each represents a hydrogen atom or a methyl group.

[0222] R 7 and R 10 Each represents an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 40 carbon atoms.

[0223] n9 represents an integer where 1 ≤ n9 ≤ 3, n 10 It means 2≤n 10 Integers ≤ 5, n 11 It means 0≤n 11 Integers ≤ 3, n 12 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.

[0224] n 13 It means 1≤n 13 Integers ≤ 3, n 14 This 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.

[0225] m2 represents an integer from 2 to 10.

[0226] As Q 2 Examples of m2-valent organic groups include those with 1 to 4 carbon atoms.

[0227] Examples of compounds represented by formula (G-1) or formula (G-2) include the following compounds.

[0228]

[0229] Examples of compounds represented by formula (G-3) or formula (G-4) include the following compounds.

[0230]

[0231] 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.

[0232] Among them, glycourea compounds are preferred, specifically tetrahydroxymethylglycourea, tetramethoxyglycourea, tetramethoxymethylglycourea, compounds of tetrahydroxymethylglycourea with 1 to 4 hydroxymethyl groups methoxymethylated or mixtures thereof, compounds of tetrahydroxymethylglycourea with 1 to 4 hydroxymethyl groups acylmethylated or mixtures thereof, and more preferably tetramethoxymethylglycourea.

[0233] The molecular weight of the crosslinking agent (C) is not particularly limited, but is preferably 1,000 or less.

[0234] The content of the crosslinking agent (C) in the composition for forming the lower layer of the resist film is not particularly limited, and is, for example, 1% to 70% by mass, preferably 5% to 60% by mass relative to the resin (A).

[0235] <Cure Catalyst (D)>

[0236] Regarding the curing catalyst (D) included as an optional component in the composition for forming the lower layer film of the resist, both thermal acid-generating agents and photo-acid-generating agents can be used, but thermal acid-generating agents are preferred.

[0237] Examples of heat-generating acid agents include p-toluenesulfonic acid, trifluoromethanesulfonic acid, and pyridine. - p-Toluenesulfonate (pyridine) -p-Toluenesulfonic acid), pyridine Phenolsulfonic acid, pyridine - p-Hydroxybenzenesulfonic acid (p-phenolsulfonic acid pyridine) salt), pyridine - Sulfonic acid compounds and carboxylic acid compounds such as trifluoromethanesulfonic acid, 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.

[0238] Examples of photoacid-generating agents include, Salt compounds, sulfonylimide compounds, and disulfonyldiazomethane compounds, etc.

[0239] 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 Salt compounds, as well as sulfonium salt compounds such as triphenylsulfonium hexafluoroantimonate, triphenylsulfonium nonafluoro n-butane sulfonate, triphenylsulfonium camphor sulfonate, and triphenylsulfonium trifluoromethane sulfonate.

[0240] Examples of sulfonylimide compounds include N-(trifluoromethanesulfonyloxy)succinimide, N-(nonafluoron-butanesulfonyloxy)succinimide, N-(camphorsulfonyloxy)succinimide, and N-(trifluoromethanesulfonyloxy)naphthalenediformimide.

[0241] Examples of disulfonyldiazomethane compounds include, for example, bis(trifluoromethylsulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, bis(phenylsulfonyl)diazomethane, bis(p-toluenesulfonyl)diazomethane, bis(2,4-dimethylbenzenesulfonyl)diazomethane, and methylsulfonyl-p-toluenesulfonyldiazomethane.

[0242] The curing catalyst (D) can be used alone, or two or more can be used in combination.

[0243] 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.

[0244] <Other Ingredients>

[0245] In the composition for forming the lower layer of the resist film, a surfactant can be added to further improve the coating properties on uneven surfaces in order to prevent pinholes, streaks, etc.

[0246] Examples of surfactants include, for instance, linear or branched alkylbenzene sulfonic acids (e.g., dodecylbenzene sulfonic acid), polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene oil-based ether, polyoxyethylene alkyl aryl ether, polyoxyethylene octylphenol ether, polyoxyethylene nonylphenol ether, polyoxyethylene / polyoxypropylene block copolymers, sorbitol monolaurate, sorbitol monopalmitate, sorbitol monostearate, sorbitol monooleate, sorbitol trioleate, sorbitol tristearate, and other sorbitol fatty acid esters, polyoxyethylene sorbitol monolaurate, polyoxyethylene sorbitol monopalmitate, polyoxyethylene sorbitol monostearate, and polyoxyethylene sorbitol monolaurate. Nonionic surfactants such as sorbitol trioleate, polyoxyethylene sorbitol tristearate, and other polyoxyethylene sorbitol fatty acid esters; Eptop EF301, EF303, EF352 (manufactured by Tokem Prodact, trade name); Megafack F171, F173, R-30 (manufactured by DIC Co., Ltd., trade name); Florad FC Fluorinated surfactants such as 430, FC431 (manufactured by Sumitomo Silem Co., Ltd., trade name), Asahigard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by AGC Co., Ltd., trade name), and organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), etc.

[0247] The amount of these surfactants mixed in is typically 2.0% by mass or less, and preferably 1.0% by mass or less, relative to the total solid content of the composition for forming the lower layer of the resist film.

[0248] These surfactants can be added individually or in combination of two or more.

[0249] The composition for forming the resist underlayer film may include a polymerization inhibitor (free radical scavenger) as needed. Examples of polymerization inhibitors include, for example, 2,6-diisobutylphenol, 3,5-di-tert-butylphenol, 3,5-di-tert-butylcresol, hydroquinone, hydroquinone monomethyl ether, pyrogallol, tert-butylcatechol, 4-methoxy-1-naphthol, etc.

[0250] There is no particular limitation on the content of the polymerization inhibitor in the composition for forming the lower layer film of the resist, but it is preferably less than 1% by mass relative to the solid content.

[0251] The composition for forming the lower layer of the resist film of the present invention contains solid components, that is, components other than the solvent mentioned above, in the form of 0.01% to 10% by mass.

[0252] The composition for forming the resist underlayer is suitable for use in EUV (extreme ultraviolet) exposure processes.

[0253] The composition for forming a resist underlayer film is suitable for use in the formation of an underlayer film of a metal-containing resist.

[0254] (Underlying film of the resist)

[0255] The resist underlayer film of the present invention is a cured product of the above-mentioned resist underlayer film forming composition.

[0256] The resist underlayer film can be manufactured, for example, by coating the above-mentioned resist underlayer film forming composition onto a semiconductor substrate and then firing it.

[0257] 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.

[0258] When using a semiconductor substrate on which an inorganic film has been formed on its surface, this inorganic film can be 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, for instance, 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.

[0259] The resist underlayer film formation composition of the present invention is coated on such a semiconductor substrate using a suitable coating method such as a spin coater or a coating machine. Then, the resist underlayer film is formed by baking using a heating means such as a heating plate. 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.

[0260] 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 (5nm)~0.05μm(50nm), 0.003μm(3nm)~0.03μm(30nm), 0.003μm(3nm)~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).

[0261] The method for determining the thickness of the resist underlayer film in this specification is as follows.

[0262] Name of measuring device: Elliptic film thickness measuring device RE-3100 (SCREEN Co., Ltd.) SWE (Single Wavelength Ellipsometry) Mode The arithmetic mean of 8 points (e.g., measurements taken at 1 cm intervals along the X direction of the wafer). (Laminated structure) The stack of the present invention comprises a semiconductor substrate and a photoresist underlayer film of the present invention.

[0263] Examples of semiconductor substrates include the aforementioned semiconductor substrate.

[0264] The photoresist underlayer is, for example, disposed on a semiconductor substrate.

[0265] (Semiconductor device manufacturing methods, patterning methods)

[0266] The method for manufacturing the semiconductor device of the present invention includes at least the following steps.

[0267] The process of forming a photoresist underlayer film on a semiconductor substrate using the photoresist underlayer film forming composition of the present invention; and The process of forming a resist film on the resist underlayer film. The pattern forming method of the present invention includes at least the following steps.

[0268] 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 resist underlayer film. The process of irradiating a photoresist film with light or an electron beam, followed by developing the photoresist film to obtain a photoresist pattern; and The process of using a resist pattern as a mask and then etching the underlying resist film. Typically, a resist film is formed on the lower layer of the resist film.

[0269] The thickness of the resist film 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.

[0270] As a photoresist film formed on a resist underlayer by known methods (e.g., coating and firing of the photoresist 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.

[0271] It should be noted that, in this specification, the EB-responsive resist is also referred to as a photoresist.

[0272] As photoresists, there are positive photoresists composed of phenolic varnish resin and 1,2-naphthoquinone diazonyl sulfonate; chemically amplified photoresists composed of binders and photoacid generators having groups that increase the rate of alkali dissolution through acid decomposition; chemically amplified photoresists composed of low-molecular-weight compounds that increase the rate of alkali dissolution through acid decomposition, alkali-soluble binders, and photoacid generators; chemically amplified photoresists composed of binders that increase the rate of alkali dissolution through acid decomposition, low-molecular-weight compounds that increase the rate of alkali dissolution through acid decomposition, and photoacid generators; and photoresists containing metal elements, etc. Examples of such photoresists include those manufactured by JSR Corporation under the trade name V146G, those manufactured by Shiplay Corporation under the trade name APEX-E, those manufactured by Sumitomo Chemical Co., Ltd. under the trade name PAR710, and those manufactured by Shin-Etsu Chemical Industry Co., Ltd. under the trade names AR2772 and SEPR430. Furthermore, examples of fluorinated atom polymer-based photoresists can be found in publications such as Proc. SPIE, Vol. 3999, 330-334 (2000), Proc. SPIE, Vol. 3999, 357-364 (2000), and Proc. SPIE, Vol. 3999, 365-374 (2000).

[0273] In addition, the following can be used: 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 high-resolution pattern forming compositions 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 not limited to these.

[0274] Examples of resist compositions include, for example, the following compositions.

[0275] 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 protected by protecting groups whose polar groups are removed by the action of acid.

[0276]

[0277] In the general formula (121), m represents an integer from 1 to 6.

[0278] R1 and R2 each independently represent a fluorine atom or a perfluoroalkyl group.

[0279] L1 represents -O-, -S-, -COO-, -SO2-, or -SO3-.

[0280] L2 indicates that it can have alkylene groups or single bonds that have substituents.

[0281] W1 represents a cyclic organic group that can have substituents.

[0282] M ＋ It represents a cation.

[0283] 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.

[0284] A radiation-sensitive resin composition comprising a polymer and an acid-generating agent, wherein the polymer has a first structural unit represented by the following formula (31) and a second structural unit represented by the following formula (32) and containing an acid-dissociating group.

[0285]

[0286] (In formula (31), Ar is a group from aromatic hydrocarbons with 6 to 20 carbon atoms from which (n+1) hydrogen atoms have been removed. R 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 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 acidic 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.)

[0287] 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 acid-instantaneous groups.

[0288]

[0289] [In the formula,] R 2 X represents an alkyl group, hydrogen atom, or halogen atom that can have 1 to 6 carbon atoms and may contain halogen atoms. 1 Indicates a single bond, -CO-O- or -CO-NR 4 - , R represents the bond with -Ar. 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.

[0290] A photoresist film comprising a base resin comprising 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.

[0291]

[0292] (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 single bond, a phenylene or naphthylene group, or a linker group containing 1 to 12 carbon atoms selected from at least one of ester bonds, lactone rings, phenylene, and naphthylene groups. X 2 (These can be single bonds, ester bonds, or amide bonds.)

[0293] Examples of resist materials include the following.

[0294] A corrosion resist material comprising a polymer having repeating units as shown in formula (b1) or formula (b2).

[0295]

[0296] (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. X 2 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 replaced by an ether group, an ester group, or a group containing an lactone ring. Furthermore, 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 replaced by an ether group or an ester group. Rf 1 ~Rf 4 Each atom is independently a hydrogen atom, a fluorine atom, or a trifluoromethyl atom, but at least one of them is a fluorine atom or a trifluoromethyl atom. Furthermore, 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, sulfone, or a group containing a sulfonate salt. A portion of the methylene group constituting these groups may be substituted with an ether, ester, carbonyl, carbonate, or sulfonate group. Furthermore, R... 1 With R 2 They can combine with sulfur atoms to form rings.

[0297] An anti-corrosion material comprising a base resin, wherein the base resin comprises a polymer containing repeating units as shown in formula (a).

[0298]

[0299] (In equation (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.

[0300] A photoresist composition is a photoresist composition in which acid is generated upon exposure, and its solubility in a developing solution changes due to 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 aforementioned 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).

[0301]

[0302] [In equation (f2-r-1), Rf] 21 Each is independently a hydrogen atom, alkyl group, alkoxy group, hydroxy group, hydroxyalkyl group, or cyano group. n” is an integer from 0 to 2. [This is a bonding bond.]

[0303] 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).

[0304]

[0305] 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 a divalent linker. R 2 Each is an organic group containing a fluorine atom.

[0306] As a corrosion resist composition, it can be a corrosion resist containing metal.

[0307] Metal-containing photoresists are also known as metal oxide photoresists (MOR), with tin oxide photoresists being a representative example.

[0308] As a metal oxide resist material, examples include, for instance, the coating composition disclosed in Japanese Patent Application Publication No. 2019-113855, which contains a metal oxygen-hydroxyl network having organic ligands through metal carbon bonds and / or metal carboxylate bonds.

[0309] One example of a metal-containing corrosion resist uses a peroxide ligand as a radiation-sensitive stabilizing ligand. The peroxide-based metal oxygen-hydroxy compound is described in detail, for example, in paragraph

[0011] of Japanese Publication No. 2019-532489. Examples of such patent documents include, for instance, U.S. Patent No. 9,176,377B2, U.S. Patent Application Publication No. 2013 / 0224652A1, U.S. Patent No. 9,310,684B2, U.S. Patent Application Publication No. 2016 / 0116839A1, and U.S. Patent Application Publication No. 15 / 291738.

[0310] Coatings containing a metal oxygen-hydroxyl network with organic ligands via metal carbon bonds and / or metal carboxylate bonds.

[0311] Compositions based on inorganic oxygen / hydroxyl groups.

[0312] A coating solution comprising: an organic solvent; and a first organometallic composition of formula R z SnO (2-(z / 2)-(x / 2)) (OH) x (Here, 0 < z ≤ 2 and 0 < (z + x) ≤ 4), Equation R' n SnX 4-n (Here, n = 1 or 2) or mixtures 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; and a hydrolytic metal compound, which is of formula MX' v (Here, M is a metal selected from groups 2 to 16 of the periodic table, v = 2 to 6, and X' is a ligand of a hydrolyzable MX bond or a combination thereof.)

[0313] 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 on a secondary or tertiary carbon atom.

[0314] An aqueous solution of an inorganic pattern-forming precursor comprises a mixture of water, a low-oxide metal cation, a polyatomic inorganic anion, and a radiation-sensitive ligand comprising a peroxide group.

[0315] Other examples of metal-containing corrosion inhibitors include the compositions described in Japanese Patent Application Publication No. 2011-253185, WO2015 / 026482, WO2016 / 065120, WO2017 / 066319, WO2017 / 156388, WO2018 / 031896, Japanese Patent Application Publication No. 2020-122959, Japanese Patent Application Publication No. 2020-122960, WO2019 / 099981, WO2019 / 199467, WO2019 / 195522, WO2019 / 195522, WO2020 / 210660, WO2021 / 011367 and WO2021 / 016229.

[0316] These contents are incorporated into this specification to the same extent as all that is expressly stated.

[0317] There are no particular limitations on the method of forming a metal-containing resist film from a metal-containing resist. For example, a method can be used to coat a coating type resist material (a composition for forming a metal-containing resist film) as a metal-containing resist and then fire it.

[0318] Furthermore, metal-containing resist films can be formed by vapor deposition. As a method for forming metal-containing resist films by vapor deposition, for example, the method described in Japanese Patent Application Publication No. 2017-116923 is included in this specification to the same extent as all of the contents explicitly stated therein. It should be noted that in Japanese Patent Application Publication No. 2017-116923, the metal-containing resist film of the present invention is referred to as a film containing metal oxides.

[0319] Irradiation with light or electron beams is performed, for example, by using a mask (photomask) to form a prescribed pattern. Examples of methods used include i-rays, KrF excimer lasers, ArF excimer lasers, EUV (ultra-ultraviolet) lasers, or EB (electron beam). The resist underlayer film formation composition of the present invention is preferably used for EB (electron beam) or EUV (ultra-ultraviolet: 13.5 nm) irradiation, and more preferably for EUV (ultra-ultraviolet) exposure.

[0320] There are no particular restrictions on the irradiation energy of the electron beam and the amount of light exposure.

[0321] It can be baked after exposure to light or electron beams and before development (PEB: Post Exposure Bake).

[0322] 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.

[0323] 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.

[0324] In development, for example, alkaline developing solutions or organic solvents are used.

[0325] Examples of developing temperatures include, for example, 5°C to 50°C.

[0326] Examples of development times include, for example, 10 seconds to 300 seconds.

[0327] 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, an appropriate amount of surfactants such as isopropanol or 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 an organic solvent such as butyl acetate instead of an alkaline developer to develop the portion of the photoresist where the alkaline dissolution rate is not improved.

[0328] As a developer for a metal-containing photoresist, an organic solvent can be used, and development is performed by passing the developer (solvent) after irradiation with light or an electron beam. Thus, for example, when a negative metal-containing photoresist film is used, the unexposed portions of the metal-containing photoresist film are removed, forming a pattern of the metal-containing photoresist film.

[0329] Examples of organic solvents used as developers include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl acetate, ethyl methoxyacetate, ethyl ethoxyacetate, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monophenyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, 2-methoxybutyl acetate, 3-methoxybutyl acetate, 4-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-ethyl-3-methoxybutyl acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, 2-ethoxybutyl acetate, 4-methoxybutyl acetate, 4-methoxybutyl acetate -Ethoxybutylacetic acid ester, 4-propoxybutylacetic acid ester, 2-methoxypentylacetic acid ester, 3-methoxypentylacetic acid ester, 4-methoxypentylacetic acid ester, 2-methyl-3-methoxypentylacetic acid ester, 3-methyl-3-methoxypentylacetic acid ester, 3-methyl-4-methoxypentylacetic acid ester, 4-methyl-4-methoxypentylacetic acid ester, propylene glycol diacetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate Examples include esters, butyl lactate, propyl lactate, ethyl carbonate, propyl carbonate, butyl carbonate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, methyl acetoacetate, ethyl acetoacetate, methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, and propyl 3-methoxypropionate. Furthermore, surfactants may be added to these developing solutions.

[0330] 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.

[0331] 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.

[0332] Example

[0333] The following examples illustrate the content of the present invention in detail, but the present invention is not limited to them.

[0334] The weight-average molecular weights of the polymers shown in Synthetic Examples 1-8 and Comparative Synthetic Examples 1-2 below are the results obtained by gel permeation chromatography (hereinafter referred to as GPC). A GPC apparatus manufactured by Toso Corporation was used in the determination, and the determination conditions are as follows.

[0335] GPC column: TSKgel Super-MultiporeHZ-N (2 columns)

[0336] Column temperature: 40℃

[0337] Solvent: Tetrahydrofuran (THF)

[0338] Flow rate: 0.35 ml / min

[0339] Standard sample: Polystyrene (manufactured by Tosoo Corporation)

[0340] <Synthesis example 1>

[0341] A solution of 20.00 g of polyethylene glycol monomethacrylate (manufactured by Nippon Oil Co., Ltd., product name: Brenmar PE90), 1.36 g of azobisisobutyronitrile (manufactured by Tokyo Chemical Industry Co., Ltd.), and 32.00 g of propylene glycol monomethyl ether was added to a dropping funnel. The solution was then added dropwise to a reaction flask containing 15.48 g of propylene glycol monomethyl ether under a nitrogen atmosphere at 100°C. The mixture was heated and stirred for 24 hours to obtain a polymer solution. This polymer solution did not produce any turbidity even after cooling to room temperature and exhibited good solubility in propylene glycol monomethyl ether. GPC analysis was performed, and the weight-average molecular weight of the polymer in the obtained solution, converted to standard polystyrene, was 4000. The polymer obtained in this synthetic example has the structural unit shown in formula (1a).

[0342]

[0343] <Synthesis example 2>

[0344] A solution of 20.00 g of polyethylene glycol monomethacrylate (manufactured by Nippon Oil Co., Ltd., product name: Brenmar PE200, average addition molar number 4.5), 1.46 g of azobisisobutyronitrile (manufactured by Tokyo Chemical Industry Co., Ltd.), and 33.29 g of propylene glycol monomethyl ether was added to a dropping funnel. The solution was then added dropwise to a reaction flask containing 15.72 g of propylene glycol monomethyl ether under a nitrogen atmosphere at 100°C. The mixture was heated and stirred for 24 hours to obtain a polymer solution. This polymer solution did not produce any turbidity even after cooling to room temperature and exhibited good solubility in propylene glycol monomethyl ether. GPC analysis was performed, and the weight-average molecular weight of the polymer in the obtained solution, converted to standard polystyrene, was 4000. The polymer obtained in this synthetic example has the structural unit shown in formula (1b).

[0345]

[0346] n is 4.5.

[0347] <Synthesis Example 3>

[0348] A solution of 10.00 g of polyethylene glycol monomethacrylate (manufactured by Nippon Oil Co., Ltd., product name: Brenmar PE90), 3.64 g of glycidyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.72 g of azobisisobutyronitrile (manufactured by Tokyo Chemical Industry Co., Ltd.), and 29.03 g of propylene glycol monomethyl ether was added to a dropping funnel. The solution was then added dropwise to a reaction flask containing 14.41 g of propylene glycol monomethyl ether under a nitrogen atmosphere at 100°C. The mixture was heated and stirred for 24 hours to obtain a polymer solution. This polymer solution did not produce any turbidity even after cooling to room temperature and exhibited good solubility in propylene glycol monomethyl ether. GPC analysis was performed, and the weight-average molecular weight of the polymer in the obtained solution, converted to standard polystyrene, was 4000. The polymer obtained in this synthetic example has the structural units shown in formulas (1a) and (1c) below.

[0349]

[0350] <Synthesis example 4>

[0351] 20.00 g of the polymer solution obtained in Synthesis Example 3, 1.89 g of methacrylic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), and tetrabutyl bromide were used. 0.34 g of propylene glycol monomethyl ether (manufactured by ACROSS) and 0.28 g of hydroquinone (manufactured by Tokyo Chemical Industry Co., Ltd.) were dissolved in 25.02 g of propylene glycol monomethyl ether in a reaction vessel. After purging the reaction vessel with nitrogen, the reaction was carried out at 120°C for 24 hours to obtain a polymer solution. This polymer solution did not produce turbidity even when cooled to room temperature and showed good solubility in propylene glycol monomethyl ether. GPC analysis was performed, and the polymer in the obtained solution had a weight-average molecular weight of 5000 converted to standard polystyrene. The polymer obtained in this synthetic example has the structural units shown in formulas (1a) and (1d) below.

[0352]

[0353] <Comparative Synthesis Example 1>

[0354] A solution of 20.00 g of 2-hydroxyethyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.), 1.26 g of azobisisobutyronitrile (manufactured by Tokyo Chemical Industry Co., Ltd.), and 47.53 g of propylene glycol monomethyl ether was added dropwise to a reaction flask containing 28.71 g of propylene glycol monomethyl ether under a nitrogen atmosphere at 100°C. The mixture was heated and stirred for 24 hours to obtain a polymer solution. This polymer solution did not produce any turbidity even after cooling to room temperature and exhibited good solubility in propylene glycol monomethyl ether. GPC analysis was performed, and the polymer in the obtained solution had a weight-average molecular weight of 6000 converted from standard polystyrene. The polymer obtained in this synthetic example has the structural unit shown in formula (2a).

[0355]

[0356] <Synthesis example 5>

[0357] 10.00 g of ethylene glycol diglycidyl ether (manufactured by Kyoeisha Chemical Co., Ltd., product name: Eporite 40E), 4.66 g of fumaric acid (manufactured by Tokyo Chemical Industry Co., Ltd.), and tetrabutyl bromide were prepared. 0.65 g of (manufactured by ACROSS) was added to 23.34 g of propylene glycol monomethyl ether in a reaction vessel and dissolved. After purging the reaction vessel with nitrogen, the reaction was carried out at 90°C for 24 hours to obtain a polymer solution. This polymer solution did not produce turbidity even when cooled to room temperature and showed good solubility in propylene glycol monomethyl ether. GPC analysis was performed, and the polymer in the obtained solution had a weight-average molecular weight of 3000 converted from standard polystyrene. The polymer obtained in this synthetic example has the structure shown in formulas (11a) and (12a) below.

[0358]

[0359] <Synthesis example 6>

[0360] 10.00g of diethylene glycol diglycidyl ether (manufactured by Kyoeisha Chemical Co., Ltd., product name: Eporite 100E), 3.97g of fumaric acid (manufactured by Tokyo Chemical Industry Co., Ltd.), and tetrabutyl bromide were prepared. 0.55 g of propylene glycol monomethyl ether (manufactured by ACROSS) was added to 22.11 g of propylene glycol monomethyl ether in a reaction vessel and dissolved. After purging the reaction vessel with nitrogen, the reaction was carried out at 90°C for 24 hours to obtain a polymer solution. This polymer solution did not produce turbidity even when cooled to room temperature and showed good solubility in propylene glycol monomethyl ether. GPC analysis was performed, and the polymer in the obtained solution had a weight-average molecular weight of 3000 converted from standard polystyrene. The polymer obtained in this synthetic example has the structure shown in formulas (11b) and (12a) below.

[0361]

[0362] <Synthesis Example 7>

[0363] 10.00g of polyethylene glycol diglycidyl ether (manufactured by Kyoeisha Chemical Co., Ltd., product name: Eporite 400E), 2.38g of fumaric acid (manufactured by Tokyo Chemical Industry Co., Ltd.), and tetrabutyl bromide were prepared. 0.33 g of (manufactured by ACROSS) was added to 19.27 g of propylene glycol monomethyl ether in the reaction vessel and dissolved. After purging the reaction vessel with nitrogen, the reaction was carried out at 90°C for 24 hours to obtain a polymer solution. This polymer solution did not produce turbidity even when cooled to room temperature and showed good solubility in propylene glycol monomethyl ether. GPC analysis was performed, and the polymer in the obtained solution had a weight-average molecular weight of 3000 converted to standard polystyrene. The polymer obtained in this synthetic example has the structure shown in formulas (11c) and (12a) below.

[0364]

[0365] n: Approximately 9

[0366] <Synthesis example 8>

[0367] 10.00 g of ethylene glycol diglycidyl ether (manufactured by Kyoeisha Chemical Co., Ltd., product name: Eporite 40E), 7.32 g of 5-hydroxyisophthalic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), and tetrabutyl bromide were prepared. 1.30 g of (manufactured by ACROSS) was dissolved in 27.99 g of propylene glycol monomethyl ether in a reaction vessel. After purging the reaction vessel with nitrogen, the reaction was carried out at 105°C for 24 hours to obtain a polymer solution. This polymer solution did not produce turbidity even when cooled to room temperature and showed good solubility in propylene glycol monomethyl ether. GPC analysis was performed, and the polymer in the obtained solution had a weight-average molecular weight of 4000 converted from standard polystyrene. The polymer obtained in this synthesis example has the structure shown in formulas (11a) and (12b) below.

[0368]

[0369] <Comparative Synthesis Example 2>

[0370] 7.00 g of monoallyl diglycidyl isocyanuric acid (manufactured by Shikoku Chemical Industry Co., Ltd.), 3.47 g of fumaric acid (manufactured by Tokyo Chemical Industry Co., Ltd.), and tetrabutyl bromide were prepared. 0.42 g of (manufactured by ACROSS) was added to 16.59 g of propylene glycol monomethyl ether in the reaction vessel and dissolved. After purging the reaction vessel with nitrogen, the reaction was carried out at 90°C for 24 hours to obtain a polymer solution. This polymer solution did not produce turbidity even when cooled to room temperature and showed good solubility in propylene glycol monomethyl ether. GPC analysis was performed, and the polymer in the obtained solution had a weight-average molecular weight of 4000 converted from standard polystyrene. The polymer obtained in this synthesis example has the structure shown in formulas (11d) and (12a) below.

[0371]

[0372] (Preparation of the composition for forming the lower layer film of the photoresist)

[0373] (Example, Comparative Example)

[0374] The polymers, crosslinking agents, curing catalysts, and solvents obtained in the above synthesis examples 1-2, 4-8, and comparative synthesis examples 1-2 were mixed in the proportions shown in Tables 1-1 and 1-2, and filtered through a 0.1 μm fluororesin filter to prepare compositions for forming a resist underlayer film.

[0375] The abbreviations in Tables 1-1 and 1-2 are as follows.

[0376] PL-LI: Tetramethoxymethylglyoxal

[0377] Py-PSA: Pyridine - p-hydroxybenzenesulfonic acid

[0378] PGMEA: Propylene glycol monomethyl ether acetate

[0379] PGME: Propylene Glycol Monomethyl Ether

[0380] [Table 1-1]

[0381] [Table 1-2]

[0382] [Dissolution test in photoresist solvent]

[0383] The resist underlayer film forming compositions of Examples 1-7 and Comparative Examples 1-2 were respectively coated onto silicon wafers serving as semiconductor substrates using a spin coater. The silicon wafers were placed on a hot plate and baked at 205°C for 1 minute to form a resist underlayer film (film thickness 5 nm). These resist underlayer films were immersed in a mixed solvent of propylene glycol monomethyl ether (70 vol%) and propylene glycol monomethyl ether acetate (30 vol%), used as the solvent for the photoresist forming composition, at room temperature for 1 minute. After removing the solvent by heating at 100°C for 30 seconds, the film thickness was measured. The results of the solvent resistance test are shown in Tables 2-1 and 2-2. A reduction in film thickness of 2% or less (1 Å or less) was recorded as "good," and a reduction in film thickness exceeding 2% was recorded as "poor."

[0384] [Table 2-1]

[0385] [Table 2-2]

[0386] (Formation of resist pattern using EUV exposure: negative organic solvent development)

[0387] The resist underlayer film formation compositions of Examples 1-2, Examples 4-5, and Comparative Examples 1-2 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 resist solution (tin oxide-based resist) was further spin-coated onto the wafer, and the wafer was heated at 130°C for 1 minute to form an EUV resist layer. Exposure was then performed using an ASML EUV exposure apparatus (NXE3300B) under the conditions of NA = 0.33, σ = 0.67 / 0.90, and Dipole. It should be noted that during exposure, exposure was performed using a mask set to form dense lines with a line width and gap width (L / S) of 1 / 1, such that the line width and gap width (L / S) of the EUV resist after development would be 14 nm.

[0388] After exposure, post-exposure heating (PEB, 170°C for 1 minute) was performed, followed by cooling on a cooling plate to room temperature. Development was then carried out using an organic solvent (propylene glycol monomethyl ether acetate) for 60 seconds, followed by rinsing to form the resist pattern. The length of the resist pattern was measured using a scanning electron microscope (manufactured by Hitachi High Tech Noroze Co., Ltd., CG4100). The exposure required to obtain a pattern with a CD size of 14 nm was determined in the formation of the resist pattern described above, and is shown in Tables 3-1 and 3-2. Lower numbers indicate that the target pattern was obtained with less exposure.

[0389] [Table 3-1]

[0390] [Table 3-2]

[0391] The evaluation results clearly show that by introducing ethylene glycol groups into the polymer, patterning can be achieved with less exposure.

Claims

1. A composition for forming a photoresist underlayer film, comprising a resin (A) and a solvent (B), The resin (A) is a polymer comprising structural units shown in formula (1) or formula (2) below. In equation (1), R 1 R represents an alkyl group having 1 to 3 hydrogen atoms or carbon atoms. 2 Indicates a hydrogen atom, methyl or ethyl, and p is the average molar number of additions, which is 2 to 20; In equation (2), Q represents a divalent group without sulfur atoms, and q is the average number of moles of addition, which is 1 to 20.

2. The composition for forming a resist underlayer film according to claim 1, wherein Q in formula (2) is represented by formula (2-1) or formula (2-2). In equation (2-1), Q 1 The terms n1 and n2 represent alkylene, alkenylene, ynylene, phenylene, naphthylene, or anthracene, wherein the phenylene, naphthylene, and anthracene may each be independently substituted by a group selected from alkyl, halogen, alkoxy, nitro, cyano, and hydroxyl groups having 1 to 6 carbon atoms; n1 and n2 each independently represent 0 or 1. In equation (2-2), X 1 Z represents any of the groups shown in formulas (2-2-1) to (2-2-3) below; 1 and Z 2 Each can independently represent a single bond or a group represented by the following formula (2-2-4); Indicates a bonding bond; In equations (2-2-1) to (2-2-3), R 11 and R 12 Each of these groups independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, a benzyl group, or a phenyl group. The benzyl and phenyl groups may be substituted with groups selected from alkyl groups having 1 to 6 carbon atoms, halogen groups, alkoxy groups having 1 to 6 carbon atoms, nitro groups, cyano groups, hydroxyl groups, and alkylthio groups having 1 to 6 carbon atoms. Furthermore, R... 11 With R 12 They can combine with each other to form rings with 3 to 6 carbon atoms; R 13 The group represents an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, a benzyl group, or a phenyl group. Furthermore, the benzyl group and the phenyl group can each be independently substituted by a group selected from alkyl groups having 1 to 6 carbon atoms, halogen groups, alkoxy groups having 1 to 6 carbon atoms, nitro groups, cyano groups, and hydroxyl groups. Indicates a bonding bond; 1 represents the bonding bond with the carbon atom in formula (2-2); 2 represents the bonding bond with the nitrogen atom in formula (2-2); In equation (2-2-4), m represents an integer from 1 to 4; n represents an integer from 0 to 4; p1 and p2 each independently represent 0 or 1; 3 represents the bonding bond with the nitrogen atom in formula (2-2); 4 represents a bonding bond.

3. The composition for forming a resist underlayer film according to claim 1, wherein the resin (A) is a polymer (1) comprising the structural unit shown in formula (1), The polymer (1) contains at least 50% by mass of the structural unit represented by formula (1).

4. The composition for forming a resist underlayer film according to claim 1, wherein the resin (A) is a polymer (2) comprising the structural unit shown in formula (2). The mass percentage of the structural unit represented by formula (2) in the polymer (2) is 50% by mass or more.

5. The composition for forming a resist underlayer film according to claim 1, wherein the solvent (B) comprises at least one selected from carboxylic acids having a hydroxyl group, linear or cyclic alkyl ketones, cyclic lactones, monoalkylene glycol monoalkyl ethers, monocarboxylic acid esters of monoalkylene glycol monoalkyl ethers, and alkoxycarboxylic acid esters of monoalkylene glycol monoalkyl ethers.

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

7. The composition for forming a resist underlayer film according to claim 6, wherein the crosslinking agent (C) is selected from at least one of amino plastic crosslinking agents and phenolic plastic crosslinking agents.

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

9. A resist underlayer film, which is a cured product of the resist underlayer film forming composition according to any one of claims 1 to 8.

10. A laminated body having Semiconductor substrates, and The resist underlayer film according to claim 9.

11. 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 8; and The process of forming a resist film on the lower resist film.

12. A method for forming a pattern, 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 8; 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, followed by developing the resist film to obtain a resist pattern; and The process of using the resist pattern as a mask and etching the underlying resist film.

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