Composition for forming resist underlayer film

Abstract

A composition for forming a resist underlayer film, which contains a polymer (A) having a repeating unit represented by formula (1) and a solvent (B). (In formula (1), X1 represents a divalent group having a ring structure and an iodine atom directly bonded to the ring structure, X2 represents a divalent group, and A1, A2, A3, A4, A5, and A6 each independently represent a hydrogen atom, a methyl group, or an ethyl group)

Description

Technical Field

[0001] The present invention relates to a resist underlayer film-forming composition, a resist underlayer film, a laminate, a method for producing a semiconductor element, and a pattern forming method. Background Art

[0002] Traditionally, microfabrication using photolithography using a resist composition has been performed in the manufacture of semiconductor devices. This microfabrication involves forming a thin film of a photoresist composition on a semiconductor substrate such as a silicon wafer. The thin film is then irradiated with active light such as ultraviolet light through a mask pattern depicting the device pattern, followed by development. The resulting photoresist pattern acts as a protective film, and the substrate is etched, thereby forming fine irregularities on the substrate surface corresponding to the photoresist pattern. In recent years, with the increasing integration of semiconductor devices, the use of active light has increased, not only with i-rays (365nm wavelength), KrF excimer lasers (248nm wavelength), and ArF excimer lasers (193nm wavelength) that have been used in the past, but also with EUV light (13.5nm wavelength) and electron beams (EB) being studied for practical application in state-of-the-art microfabrication. This has led to a significant problem in resist pattern formation caused by influences from the semiconductor substrate and other factors. Therefore, to address this issue, methods have been widely studied that involve placing a resist underlayer film between the resist and the semiconductor substrate.

[0003] Patent Document 1 discloses an antireflection film-forming composition containing a polymer having a specific structure. Patent Document 2 discloses an undercoat layer composition containing a polymer having a repeating unit derived from a specific monomer and a crosslinking agent.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: International Publication No. 2005 / 098542

[0007] Patent Document 2: Japanese Patent Application Laid-Open No. 2020-76081 Summary of the Invention

[0008] Technical problem to be solved by the invention

[0009] Examples of the properties required of the resist underlayer film include the ability to form a resist pattern with high sensitivity and a high etching rate.

[0010] The present invention has been completed in view of the above situation, and its purpose is to provide a composition for forming a resist underlayer film that can form a resist underlayer film with a high etching speed without reducing the photolithography characteristics, as well as a method for manufacturing a resist underlayer film, a laminate, and a semiconductor element using the resist underlayer film forming composition and a pattern forming method.

[0011] Technical solutions to technical problems

[0012] The present inventors have conducted intensive studies to solve the above-mentioned technical problems, and as a result, have found that the above-mentioned technical problems can be solved, thereby completing the present invention having the following gist.

[0013] That is, the present invention includes the following aspects.

[0014] [1] A resist underlayer film-forming composition comprising a polymer (A) having a repeating unit represented by the following formula (1) and a solvent (B).

[0015] [Chemistry 1]

[0016]

[0017] (In formula (1), X 1 It represents a divalent group having a ring structure and an iodine atom directly bonded to the ring structure.

[0018] X 2 represents a divalent group.

[0019] A 1 、A 2 、A 3 、A 4 、A 5 and A 6 Each independently represents a hydrogen atom, a methyl group or an ethyl group.)

[0020] [2] The resist underlayer film-forming composition according to [1], wherein X in the formula (1) 1 It represents any one of a group represented by the following formula (2-1), a group represented by the following formula (2-2), and a group represented by the following formula (2-3).

[0021] [Chemistry 2]

[0022]

[0023] (In formula (2-1), Q 1represents a divalent organic group represented by the following formula (2-1-1), a divalent organic group represented by the following formula (2-1-2), a divalent organic group represented by the following formula (2-1-3), or a divalent organic group represented by the following formula (2-1-4). n1 and n2 each independently represent 0 or 1. Indicates a bond.

[0024] In formula (2-2), R 1 represents a hydrogen atom, a halogen atom, or an organic group having 1 to 10 carbon atoms. Indicates a bond.

[0025] In formula (2-3), R 2 represents a hydrogen atom, a halogen atom, or an organic group having 1 to 10 carbon atoms. Indicates a bond.)

[0026] [Chemistry 3]

[0027]

[0028] (In formulas (2-1-1) to (2-1-4), R 11 ~R 16 Each independently represents a halogen atom (excluding an iodine atom), a hydroxyl group, a cyano group, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkenyloxy group having 2 to 6 carbon atoms, an alkynyloxy group having 2 to 6 carbon atoms, an acyl group having 2 to 6 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, an arylcarbonyl group having 7 to 13 carbon atoms, an aralkyl group having 7 to 13 carbon atoms, or -N(R a )(R b )(R a and R b Each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. ). Indicates a bond.

[0029] In formula (2-1-1), p11 represents an integer from 0 to 2. When p11 is 0, m11 represents an integer from 1 to 4, n11 represents an integer from 0 to 3, and the total of m11 and n11 is 4 or less. When p11 is 1, m11 represents an integer from 1 to 6, n11 represents an integer from 0 to 5, and the total of m11 and n11 is 6 or less. When p11 is 2, m11 represents an integer from 1 to 8, n11 represents an integer from 0 to 7, and the total of m11 and n11 is 8 or less. 11 When there are 2 or more, 2 or more R 11 It can be the same or different.

[0030] In formula (2-1-2), Z 11represents a single bond, an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or an alkylene group having 1 to 6 carbon atoms. m12 and m13 each independently represent an integer from 0 to 4, n12 and n13 each independently represent an integer from 0 to 4, the total of m12 and m13 is 1 or more, the total of m12 and n12 is 4 or less, and the total of m13 and n13 is 4 or less. In R 12 When there are 2 or more, 2 or more R 12 Can be the same or different. 13 When there are 2 or more, 2 or more R 13 It can be the same or different.

[0031] In formula (2-1-3), Z 12 and Z 13 Each independently represents a single bond, or a linear or branched alkylene group having 1 to 6 carbon atoms. m14 represents an integer from 1 to 4, n14 represents an integer from 0 to 3, and the total of m14 and n14 is 4 or less. 14 When there are 2 or more, 2 or more R 14 It can be the same or different.

[0032] In formula (2-1-4), Z 14 represents a single bond, an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or an alkylene group having 1 to 6 carbon atoms. 15 and Z 16 Each independently represents a single bond, or a linear or branched alkylene group having 1 to 6 carbon atoms. m15 and m16 each independently represent an integer from 0 to 4, n15 and n16 each independently represent an integer from 0 to 4, the total of m15 and m16 is 1 or more, the total of m15 and n15 is 4 or less, and the total of m16 and n16 is 4 or less. 15 When there are 2 or more, 2 or more R 15 Can be the same or different. 16 When there are 2 or more, 2 or more R 16 They can be the same or different.)

[0033] [3] The resist underlayer film-forming composition according to [1] or [2], wherein X in the formula (1) 2 It represents any one of a group represented by the following formula (3-1) and a group represented by the following formula (3-2).

[0034] [Chemistry 4]

[0035]

[0036] (In formula (3-1), Q 11It represents a divalent acyclic hydrocarbon group having 2 to 20 carbon atoms that may be interrupted by an oxygen atom, a divalent organic group represented by the following formula (3-1-1), a divalent organic group represented by the following formula (3-1-2), a divalent organic group represented by the following formula (3-1-3), or a divalent organic group represented by the following formula (3-1-4). n1 and n2 each independently represent 0 or 1. Indicates a bond.

[0037] In formula (3-2), X 11 represents a divalent group represented by any one of the following formulae (3-2-1) to (3-2-3). 1 and Z 2 Each independently represents a single bond or a divalent group represented by the following formula (2-2-4). Indicates a bond.)

[0038] [Chemistry 5]

[0039]

[0040] (In formulas (3-1-1) to (3-1-4), R 21 ~R 26 Each independently represents a halogen atom, a hydroxyl group, a cyano group, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkenyloxy group having 2 to 6 carbon atoms, an alkynyloxy group having 2 to 6 carbon atoms, an acyl group having 2 to 6 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, an arylcarbonyl group having 7 to 13 carbon atoms, or an aralkyl group having 7 to 13 carbon atoms. Indicates a bond.

[0041] In formula (3-1-1), p21 represents an integer from 0 to 2. When p21 is 0, n21 represents an integer from 0 to 4. When p21 is 1, n21 represents an integer from 0 to 6. When p21 is 2, n21 represents an integer from 0 to 8. 21 When there are 2 or more, 2 or more R 21 It can be the same or different.

[0042] In formula (3-1-2), Z 21 represents a single bond, an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or an alkylene group having 1 to 6 carbon atoms. n22 and n23 each independently represent an integer from 0 to 4. 22 When there are 2 or more, 2 or more R 22 Can be the same or different. 23 When there are 2 or more, 2 or more R 23 It can be the same or different.

[0043] In formula (3-1-3), Z 22 and Z 23 Each independently represents a single bond, or a linear or branched alkylene group having 1 to 6 carbon atoms. n24 represents an integer from 0 to 4. 24 When there are 2 or more, 2 or more R 24 It can be the same or different.

[0044] In formula (3-1-4), Z 24 represents a single bond, an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or an alkylene group having 1 to 6 carbon atoms. 25 and Z 26 Each independently represents a single bond, or a linear or branched alkylene group having 1 to 6 carbon atoms. n25 and n26 each independently represent an integer from 0 to 4. 25 When there are 2 or more, 2 or more R 25 Can be the same or different. 26 When there are 2 or more, 2 or more R 26 They can be the same or different.)

[0045] [Chemistry 6]

[0046]

[0047] (In formulas (3-2-1) to (3-2-3), R 1 ~R 5 Each independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom, an alkenyl group having 2 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom, an alkynyl group having 2 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom, a benzyl group, or a phenyl group, wherein the phenyl group may be substituted by at least one monovalent group selected from an alkyl group having 1 to 6 carbon atoms, a halogen atom, an alkoxy group having 1 to 6 carbon atoms, a nitro group, a cyano group, and an alkylthio group having 1 to 6 carbon atoms. 1 and R 2 They may be bonded to each other to form a ring having 3 to 6 carbon atoms. 3 and R 4 They may bond to each other to form a ring having 3 to 6 carbon atoms.

[0048] Indicates a bond. 1 represents a bond to the carbon atom in formula (3-2). 2 represents a bond to the nitrogen atom in formula (3-2).

[0049] [Chemistry 7]

[0050]

[0051] (In formula (3-2-4), m1 is an integer from 0 to 4, m2 is 0 or 1, m3 is 0 or 1, and m4 is an integer from 0 to 2. However, when m3 is 1, m1 and m2 cannot be 0 at the same time. 3 represents a bond to the nitrogen atom in formula (3-2). 4 represents a bonding bond.)

[0052] [4] The resist underlayer film-forming composition according to any one of [1] to [3], wherein the solvent (B) contains at least one selected from alkylene glycol monoalkyl ethers and monocarboxylic acid esters of alkylene glycol monoalkyl ethers.

[0053] [5] The resist underlayer film-forming composition according to any one of [1] to [4], further comprising a crosslinking agent (C).

[0054] [6] The resist underlayer film-forming composition according to any one of [1] to [5], further comprising a curing catalyst (D).

[0055] [7] A resist underlayer film which is a cured product of the resist underlayer film-forming composition according to any one of [1] to [6].

[0056] [8] A laminate comprising: a semiconductor substrate; and the resist underlayer film according to [7].

[0057] [9] A method for manufacturing a semiconductor device, comprising the following steps:

[0058] a step of forming a resist underlayer film on a semiconductor substrate using the resist underlayer film-forming composition described in any one of [1] to [6]; and

[0059] a step of forming a resist film on the resist underlayer film.

[0060]

[10] A pattern forming method comprising the following steps:

[0061] a step of forming a resist underlayer film on a semiconductor substrate using the resist underlayer film-forming composition described in any one of [1] to [6];

[0062] forming a resist film on the resist underlayer film;

[0063] irradiating the resist film with light or an electron beam, and then developing the resist film to obtain a resist pattern; and

[0064] A step of etching the resist underlayer film using the resist pattern as a mask.

[0065] Effects of the Invention

[0066] According to the present invention, a resist underlayer film-forming composition capable of forming a resist underlayer film with a high etching rate without degrading photolithographic characteristics, as well as a resist underlayer film, a laminate, a semiconductor element manufacturing method and a pattern forming method using the resist underlayer film-forming composition can be provided. DETAILED DESCRIPTION

[0067] (Resist Underlayer Film-Forming Composition)

[0068] The resist underlayer film-forming composition of the present invention contains a polymer (A) having a repeating unit represented by the following formula (1) and a solvent (B).

[0069] The resist underlayer film-forming composition may contain a crosslinking agent (C), a curing catalyst (D), and the like.

[0070] The polymer (A) has an iodine atom directly bonded to the ring structure.

[0071] When the polymer (A) has an iodine atom directly bonded to the ring structure, the etching rate of the resist underlayer film can be increased without degrading lithographic properties (e.g., sensitivity, resist pattern) compared to a case where the polymer (A) does not have an iodine atom directly bonded to the ring structure.

[0072] <Polymer (A)>

[0073] The polymer (A) has a repeating unit represented by the following formula (1).

[0074] [Chemistry 8]

[0075]

[0076] (In formula (1), X 1 It represents a divalent group having a ring structure and an iodine atom directly bonded to the ring structure.

[0077] X 2 represents a divalent group.

[0078] A 1 、A 2 、A 3 、A 4 、A 5 and A 6 Each independently represents a hydrogen atom, a methyl group or an ethyl group.)

[0079] A 1 、A 2 、A 3 、A 4 、A 5 and A6 Preferred is a hydrogen atom.

[0080] <<X 1 >>

[0081] X in formula (1) 1 The number of carbon atoms in the group is not particularly limited, and may be 4 to 20, for example.

[0082] X 1 At least an iodine atom and a carbon atom are present as atoms constituting a divalent group. 1 It may further contain a hydrogen atom, an oxygen atom, a nitrogen atom or the like as an atom constituting a divalent group.

[0083] As X 1 The ring structure in may be an aromatic ring or a non-aromatic ring.

[0084] The ring structure may be a hydrocarbon ring or a heterocyclic ring.

[0085] The ring structure is preferably an aromatic ring, more preferably an aromatic hydrocarbon ring. Examples of the aromatic hydrocarbon ring include a benzene ring, a naphthalene ring, and an anthracene ring.

[0086] Examples of the non-aromatic hydrocarbon ring include a cyclohexane ring.

[0087] In addition, as the ring structure, a uracil ring or a pyrimidinetrione ring is preferred.

[0088] Uracil refers to a heterocyclic compound represented by the following formula.

[0089] [Chemistry 9]

[0090]

[0091] Pyrimidinetrione refers to a heterocyclic compound represented by the following formula.

[0092] [Chemistry 10]

[0093]

[0094] The number of iodine atoms directly bonded to one ring structure may be one or two or more.

[0095] As X in formula (1) 1 From the viewpoint of appropriately obtaining the effects of the present invention, it is preferably any one of a group represented by the following formula (2-1) and a group represented by the following formula (2-2).

[0096] [Chemistry 11]

[0097]

[0098] (In formula (2-1), Q 1 represents a divalent organic group represented by the following formula (2-1-1), a divalent organic group represented by the following formula (2-1-2), a divalent organic group represented by the following formula (2-1-3), or a divalent organic group represented by the following formula (2-1-4). n1 and n2 each independently represent 0 or 1. Indicates a bond.

[0099] In formula (2-2), R 1 represents a hydrogen atom, a halogen atom, or an organic group having 1 to 10 carbon atoms. Indicates a bond.

[0100] In formula (2-3), R 2 represents a hydrogen atom, a halogen atom, or an organic group having 1 to 10 carbon atoms. Indicates a bond.)

[0101] In addition, "I" in formula (2-2) and formula (2-3) represents an iodine atom.

[0102] [Chemistry 12]

[0103]

[0104] (In formulas (2-1-1) to (2-1-4), R 11 ~R 16 Each independently represents a halogen atom (excluding an iodine atom), a hydroxyl group, a cyano group, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkenyloxy group having 2 to 6 carbon atoms, an alkynyloxy group having 2 to 6 carbon atoms, an acyl group having 2 to 6 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, an arylcarbonyl group having 7 to 13 carbon atoms, an aralkyl group having 7 to 13 carbon atoms, or -N(R a )(R b )(R a and R b Each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. ). Indicates a bond.

[0105] In formula (2-1-1), p11 represents an integer from 0 to 2. When p11 is 0, m11 represents an integer from 1 to 4, n11 represents an integer from 0 to 3, and the total of m11 and n11 is 4 or less. When p11 is 1, m11 represents an integer from 1 to 6, n11 represents an integer from 0 to 5, and the total of m11 and n11 is 6 or less. When p11 is 2, m11 represents an integer from 1 to 8, n11 represents an integer from 0 to 7, and the total of m11 and n11 is 8 or less. 11When there are 2 or more, 2 or more R 11 It can be the same or different.

[0106] In formula (2-1-2), Z 11 represents a single bond, an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or an alkylene group having 1 to 6 carbon atoms. m12 and m13 each independently represent an integer from 0 to 4, n12 and n13 each independently represent an integer from 0 to 4, the total of m12 and m13 is 1 or more, the total of m12 and n12 is 4 or less, and the total of m13 and n13 is 4 or less. In R 12 When there are 2 or more, 2 or more R 12 Can be the same or different. 13 When there are 2 or more, 2 or more R 13 It can be the same or different.

[0107] In formula (2-1-3), Z 12 and Z 13 Each independently represents a single bond, or a linear or branched alkylene group having 1 to 6 carbon atoms. m14 represents an integer from 1 to 4, n14 represents an integer from 0 to 3, and the total of m14 and n14 is 4 or less. 14 When there are 2 or more, 2 or more R 14 It can be the same or different.

[0108] In formula (2-1-4), Z 14 represents a single bond, an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or an alkylene group having 1 to 6 carbon atoms. 15 and Z 16 Each independently represents a single bond, or a linear or branched alkylene group having 1 to 6 carbon atoms. m15 and m16 each independently represent an integer from 0 to 4, n15 and n16 each independently represent an integer from 0 to 4, the total of m15 and m16 is 1 or more, the total of m15 and n15 is 4 or less, and the total of m16 and n16 is 4 or less. 15 When there are 2 or more, 2 or more R 15 Can be the same or different. 16 When there are 2 or more, 2 or more R 16 They can be the same or different.)

[0109] In addition, "I" in formula (2-1-1) to formula (2-1-4) represents an iodine atom.

[0110] As R in formula (2-2) 1 and R in formula (2-3) 2The organic group having 1 to 10 carbon atoms in the group includes an alkyl group having 1 to 6 carbon atoms which may have a substituent, an alkenyl group having 2 to 6 carbon atoms which may have a substituent, etc. Examples of the substituent include a halogen atom and an alkoxy group having 1 to 6 carbon atoms.

[0111] Examples of the group represented by formula (2-1) include divalent groups represented by the following formulas: These are just examples, and the group represented by formula (2-1) is not limited to these.

[0112] [Chemistry 13]

[0113]

[0114] ( Indicates a bond.)

[0115] Examples of the group represented by formula (2-2) include divalent groups represented by the following formulas: These are just examples, and the group represented by formula (2-2) is not limited to these.

[0116] [Chemistry 14]

[0117]

[0118] ( Indicates a bond.)

[0119] Examples of the group represented by formula (2-3) include divalent groups represented by the following formulas: These are just examples, and the group represented by formula (2-3) is not limited to these.

[0120] [Chemistry 15]

[0121]

[0122] ( Indicates a bond.)

[0123] <<X 2 >>

[0124] X in formula (1) 2 There are no particular restrictions as long as it is a divalent group, and it can be 1 The same divalent group can also be 1 Different divalent groups.

[0125] As X 2 The number of carbon atoms in the alkyl group is not particularly limited, and may be 4 to 20, for example.

[0126] X 2 It has at least a carbon atom as an atom constituting a divalent group. 1It may further contain a hydrogen atom, an oxygen atom, a nitrogen atom or the like as an atom constituting a divalent group.

[0127] As X in formula (1) 2 From the viewpoint of appropriately obtaining the effects of the present invention, it is preferably any one of a group represented by the following formula (3-1) and a group represented by the following formula (3-2).

[0128] [Chemistry 16]

[0129]

[0130] (In formula (3-1), Q 11 It represents a divalent acyclic hydrocarbon group having 2 to 20 carbon atoms that may be interrupted by an oxygen atom, a divalent organic group represented by the following formula (3-1-1), a divalent organic group represented by the following formula (3-1-2), a divalent organic group represented by the following formula (3-1-3), or a divalent organic group represented by the following formula (3-1-4). n1 and n2 each independently represent 0 or 1. Indicates a bond.

[0131] In formula (3-2), X 11 represents a divalent group represented by any one of the following formulae (3-2-1) to (3-2-3). 1 and Z 2 Each independently represents a single bond or a divalent group represented by the following formula (2-2-4). Indicates a bond.)

[0132] [Chemistry 17]

[0133]

[0134] (In formulas (3-1-1) to (3-1-4), R 21 ~R 26 Each independently represents a halogen atom, a hydroxyl group, a cyano group, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkenyloxy group having 2 to 6 carbon atoms, an alkynyloxy group having 2 to 6 carbon atoms, an acyl group having 2 to 6 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, an arylcarbonyl group having 7 to 13 carbon atoms, or an aralkyl group having 7 to 13 carbon atoms. Indicates a bond.

[0135] In formula (3-1-1), p21 represents an integer from 0 to 2. When p21 is 0, n21 represents an integer from 0 to 4. When p21 is 1, n21 represents an integer from 0 to 6. When p21 is 2, n21 represents an integer from 0 to 8. 21 When there are 2 or more, 2 or more R21 It can be the same or different.

[0136] In formula (3-1-2), Z 21 represents a single bond, an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or an alkylene group having 1 to 6 carbon atoms. n22 and n23 each independently represent an integer from 0 to 4. 22 When there are 2 or more, 2 or more R 22 Can be the same or different. 23 When there are 2 or more, 2 or more R 23 It can be the same or different.

[0137] In formula (3-1-3), Z 22 and Z 23 Each independently represents a single bond, or a linear or branched alkylene group having 1 to 6 carbon atoms. n24 represents an integer from 0 to 4. 24 When there are 2 or more, 2 or more R 24 It can be the same or different.

[0138] In formula (3-1-4), Z 24 represents a single bond, an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or an alkylene group having 1 to 6 carbon atoms. 25 and Z 26 Each independently represents a single bond, or a linear or branched alkylene group having 1 to 6 carbon atoms. n25 and n26 each independently represent an integer from 0 to 4. 25 When there are 2 or more, 2 or more R 25 Can be the same or different. 26 When there are 2 or more, 2 or more R 26 They can be the same or different.)

[0139] [Chemistry 18]

[0140]

[0141] (In formulas (3-2-1) to (3-2-3), R 1 ~R 5 Each independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom, an alkenyl group having 2 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom, an alkynyl group having 2 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom, a benzyl group, or a phenyl group, wherein the phenyl group may be substituted by at least one monovalent group selected from an alkyl group having 1 to 6 carbon atoms, a halogen atom, an alkoxy group having 1 to 6 carbon atoms, a nitro group, a cyano group, and an alkylthio group having 1 to 6 carbon atoms. 1 and R 2They may be bonded to each other to form a ring having 3 to 6 carbon atoms. 3 and R 4 They may bond to each other to form a ring having 3 to 6 carbon atoms.

[0142] Indicates a bond. 1 represents a bond to the carbon atom in formula (3-2). 2 represents a bond to the nitrogen atom in formula (3-2).

[0143] [Chemistry 19]

[0144]

[0145] (In formula (3-2-4), m1 is an integer from 0 to 4, m2 is 0 or 1, m3 is 0 or 1, and m4 is an integer from 0 to 2. However, when m3 is 1, m1 and m2 cannot be 0 at the same time. 3 represents a bond to the nitrogen atom in formula (3-2). 4 represents a bonding bond.)

[0146] In the present specification, examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0147] In this specification, alkyl groups are not limited to linear groups and may be branched or cyclic. Examples of linear or branched alkyl groups include methyl, ethyl, isopropyl, tert-butyl, and n-hexyl. Examples of cyclic alkyl groups (cycloalkyl groups) include cyclobutyl, cyclopentyl, and cyclohexyl.

[0148] In the present specification, examples of the alkoxy group include a methoxy group, an ethoxy group, an n-pentyloxy group, and an isopropoxy group.

[0149] In the present specification, examples of the alkylthio group include a methylthio group, an ethylthio group, an n-pentylthio group, and an isopropylthio group.

[0150] In the present specification, examples of the alkenyl group include vinyl, 1-propenyl, 2-propenyl, 1-methyl-1-vinyl, 1-butenyl, 2-butenyl, 3-butenyl, 2-methyl-1-propenyl, and 2-methyl-2-propenyl.

[0151] In the present specification, examples of the alkynyl group include groups in which the double bond of the alkenyl group exemplified above is replaced by a triple bond.

[0152] In the present specification, examples of the alkenyloxy group include vinyloxy, 1-propenyloxy, 2-n-propenyloxy (allyloxy), 1-n-butenyloxy, and prenyloxy.

[0153] In the present specification, examples of the alkynyloxy group include 2-propynyloxy, 1-methyl-2-propynyloxy, 2-methyl-2-propynyloxy, 2-butynyloxy, and 3-butynyloxy.

[0154] In the present specification, examples of the acyl group include an acetyl group and a propionyl group.

[0155] In the present specification, examples of the aryloxy group include a phenoxy group and a naphthoxy group.

[0156] In the present specification, examples of the arylcarbonyl group include a phenylcarbonyl group and the like.

[0157] In the present specification, examples of the aralkyl group include a benzyl group and a phenethyl group.

[0158] In the present specification, examples of the alkylene group include methylene, ethylene, 1,3-propylene, 2,2-propylene, 1-methylethylene, 1,4-butylene, 1-ethylethylene, 1-methylpropylene, 2-methylpropylene, 1,5-pentylene, 1-methylbutylene, 2-methylbutylene, 1,1-dimethylpropylene, 1,2-dimethylpropylene, 1-ethylpropylene, 2-ethylpropylene, 1,6-hexylene, 1,4-cyclohexylene, 1,8-octylene, 2-ethyloctylene, 1,9-nonylene, and 1,10-decylene.

[0159] As R in formulas (3-2-1) to (3-2-3) 1 ~R 5 The alkyl group having 1 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom includes, for example, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkoxyalkyl group having 2 to 10 carbon atoms, an alkoxyalkoxyalkyl group having 3 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, and an alkylthioalkyl group having 2 to 10 carbon atoms.

[0160] Furthermore, the alkyl group having 1 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom may contain two or more oxygen atoms or sulfur atoms.

[0161] As Q in formula (3-1) 11 A divalent acyclic hydrocarbon group having 2 to 20 carbon atoms which may be interrupted by an oxygen atom, for example, an alkylene group having 2 to 10 carbon atoms, -CH2CH2-(OCH2CH2) n -(n represents an integer of 1 to 9.), -CH(CH3)CH2-(OCH(CH3)CH2) n -(n represents an integer from 1 to 5.) etc.

[0162] The alkylene group having 2 to 10 carbon atoms may be linear or branched.

[0163] Examples of the group represented by formula (3-1) include the structures exemplified below.

[0164] [Chemistry 20]

[0165]

[0166] The above example is Q in formula (3-1) 11 This is an example of a divalent acyclic hydrocarbon group having 2 to 20 carbon atoms which may be interrupted by an oxygen atom.

[0167] [Chemistry 21]

[0168]

[0169] [Chemistry 22]

[0170]

[0171] [Chemistry 23]

[0172]

[0173] [Chemistry 24]

[0174]

[0175] ( Indicates a bond.)

[0176] Examples of the group represented by formula (3-2) include the structures exemplified below.

[0177] [Chemistry 25]

[0178]

[0179] [Chemistry 26]

[0180]

[0181] [Chemistry 27]

[0182]

[0183] [Chemistry 28]

[0184]

[0185] [Chemistry 29]

[0186]

[0187] ( Indicates a bond.)

[0188] The polymer (A) may have an aliphatic ring at its terminal, the carbon-carbon bond of which may be interrupted by a heteroatom. The aliphatic ring may be substituted by a substituent.

[0189] The polymer (A) is, for example, a linear polymer. The linear polymer (A) preferably has an aliphatic ring at both ends.

[0190] Examples of the substituent in the aliphatic ring which may be replaced by a substituent and in which the carbon-carbon bond may be interrupted by a heteroatom include a hydroxyl group, a carboxyl group, an alkyl group having 1 to 6 carbon atoms, an acyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, and an alkoxycarbonyl group having 2 to 6 carbon atoms.

[0191] Examples of the number of members of the aliphatic ring include a 3-membered ring to a 10-membered ring.

[0192] The aliphatic ring may be a monocyclic ring or a polycyclic ring.

[0193] The aliphatic ring may be a saturated aliphatic ring or an unsaturated aliphatic ring.

[0194] Examples of the total number of carbon atoms in the aliphatic ring which may be substituted with a substituent and in which the carbon-carbon bond may be interrupted by a heteroatom include 6 to 15.

[0195] The polymer (A) may have an aromatic ring at a terminal to which at least one of a halogen atom and a hydroxyl group may be bonded. The halogen atom is preferably an iodine atom. Examples of the aromatic ring include aromatic hydrocarbon rings and aromatic heterocycles. Examples of the aromatic hydrocarbon ring include benzene rings, naphthalene rings, and anthracene rings.

[0196] When an aliphatic ring whose carbon-carbon bond may be interrupted by a heteroatom is represented as a monovalent organic group, it is represented by the following formula (Z), for example.

[0197] [Chemistry 30]

[0198]

[0199] (In formula (Z), Z represents a monovalent organic group formed by removing one hydrogen atom from an aliphatic ring which may be substituted by a substituent and in which the carbon-carbon bond may be interrupted by a heteroatom.) Indicates a bond.)

[0200] When an aromatic ring to which at least one of a halogen atom and a hydroxyl group can be bonded is represented as a monovalent organic group, for example, a monovalent organic group represented by the above formula (Z) (wherein Z represents a monovalent organic group obtained by removing one hydrogen atom from the aromatic ring to which at least one of a halogen atom and a hydroxyl group can be bonded) is represented.

[0201] As Z, for example, the following structures can be mentioned.

[0202] [Chemistry 31]

[0203]

[0204] [Chemistry 32]

[0205]

[0206] [Chemistry 33]

[0207]

[0208] [Chemistry 34]

[0209]

[0210] In the structure, Indicates a bond.

[0211] It should be noted that "I" in the structure represents an iodine atom.

[0212] The molecular weight of the polymer (A) is not particularly limited.

[0213] The lower limit of the weight average molecular weight of the polymer (A) is, for example, 500, 1000, 2000, or 3000.

[0214] The upper limit of the weight average molecular weight of the polymer (A) is, for example, 30,000, 20,000, or 10,000.

[0215] An example of a method for producing the polymer (A) will be described.

[0216] An example of the polymer (A) can be obtained, for example, by the following reactions (I) to (II).

[0217] (I): Reaction of a compound represented by the following formula (1A) with a compound represented by the following formula (1B).

[0218] (II): Reaction of a compound represented by the following formula (1A), a compound represented by the following formula (1B), and a monocarboxyl compound having one carboxyl group.

[0219] In reactions (I) and (II), other compounds may be used in combination.

[0220] [Chemistry 35]

[0221]

[0222] (In formula (1A), X 1Compared with X in formula (1) 1 Synonymous.

[0223] In formula (1B), X 2 、A 1 、A 2 、A 3 、A 4 、A 5 and A 6 Respectively with X in formula (1) 2 、A 1 、A 2 、A 3 、A 4 、A 5 and A 6 Synonymous.)

[0224] Examples of the compound represented by formula (1A) include a compound represented by the following formula (2-1A), a compound represented by the following formula (2-2A), and a compound represented by the following formula (2-3A).

[0225] [Chemistry 36]

[0226]

[0227] (In formula (2-1A), Q 1 , n1 and n2 are respectively related to Q in formula (2-1) 1 , n1 and n2 are synonymous.

[0228] In formula (2-2A), R 1 and R in formula (2-2) 1 Synonymous.

[0229] In formula (2-3A), R 2 and R in formula (2-2) 1 Synonymous.)

[0230] In addition, "I" in Formula (2-2A) and Formula (2-3A) represents an iodine atom.

[0231] Examples of the compound represented by formula (2-1A) include the following compounds.

[0232] [Chemistry 37]

[0233]

[0234] Examples of the compound represented by formula (2-2A) include the following compounds.

[0235] [Chemistry 38]

[0236]

[0237] Examples of the compound represented by formula (2-3A) include the following compounds.

[0238] [Chemistry 39]

[0239]

[0240] Examples of the compound represented by formula (1B) include the following compounds.

[0241] [Chemistry 40]

[0242]

[0243] [Chemistry 41]

[0244]

[0245] [Chemistry 42]

[0246]

[0247] [Chemistry 43]

[0248]

[0249] [Chemistry 44]

[0250]

[0251] [Chemistry 45]

[0252]

[0253] [Chemistry 46]

[0254]

[0255] [Chemistry 47]

[0256]

[0257] [Chemistry 48]

[0258]

[0259] [Chemistry 49]

[0260]

[0261] [Chemistry 50]

[0262]

[0263] [Chemistry 51]

[0264]

[0265] Examples of the monocarboxyl compound having one carboxyl group include compounds represented by the following formula (D1).

[0266] [Chemistry 52]

[0267]

[0268] (In formula (D1), Z has the same meaning as Z in formula (Z).)

[0269] Examples of the compound represented by the following formula (D1) include the following compounds.

[0270] [Chemistry 53]

[0271]

[0272] [Chemistry 54]

[0273]

[0274] [Chemistry 55]

[0275]

[0276] [Chemistry 56]

[0277]

[0278] Reactions (I) to (II) can be carried out in the presence of a catalyst, for example. Examples of the catalyst include quaternary phosphonium salts such as tetrabutylphosphonium bromide and ethyltriphenylphosphonium bromide, and quaternary ammonium salts such as benzyltriethylammonium chloride. The amount of catalyst used can be selected from a range of 0.1 to 10% by mass relative to the total mass of the reaction raw materials used in the reaction. The optimal reaction temperature and time can be selected from a range of, for example, 80 to 160° C. and 2 to 50 hours.

[0279] The content of the polymer (A) in the resist underlayer film-forming composition is not particularly limited, but from the viewpoint of appropriately achieving the effects of the present invention, it is preferably 40% by mass to 99% by mass, more preferably 45% by mass to 95% by mass, and particularly preferably 50% by mass to 90% by mass relative to the film constituent components.

[0280] In the present invention, the film-constituting components refer to components other than the solvent contained in the composition.

[0281] Solvent (B)

[0282] The solvent (B) is not particularly limited and may be water or an organic solvent.

[0283] Examples of the organic solvent include alkylene glycol monoalkyl ethers and monocarboxylic acid esters of alkylene glycol monoalkyl ethers.

[0284] Examples of the alkylene group of the alkylene glycol monoalkyl ether include alkylene groups having 2 to 4 carbon atoms.

[0285] Examples of the alkyl group of the alkylene glycol monoalkyl ether include alkyl groups having 1 to 4 carbon atoms.

[0286] Examples of the carbon number of the alkylene glycol monoalkyl ether include 3 to 8.

[0287] Examples of the alkylene glycol monoalkyl ether include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, and propylene glycol monoethyl ether.

[0288] Examples of the alkylene group of the monocarboxylic acid ester of the alkylene glycol monoalkyl ether include an alkylene group having 2 to 4 carbon atoms.

[0289] Examples of the alkyl group of the monocarboxylic acid ester of the alkylene glycol monoalkyl ether include alkyl groups having 1 to 4 carbon atoms.

[0290] Examples of the monocarboxylic acid of the monocarboxylic acid ester of alkylene glycol monoalkyl ether include saturated monocarboxylic acids having 2 to 4 carbon atoms.

[0291] Examples of the saturated monocarboxylic acid having 2 to 4 carbon atoms include acetic acid, propionic acid, and butyric acid.

[0292] Examples of the carbon number of the monocarboxylic acid ester of the alkylene glycol monoalkyl ether include 5 to 10.

[0293] Examples of the monocarboxylic acid esters of alkylene glycol monoalkyl ethers include methyl cellosolve acetate, ethyl cellosolve acetate, propylene glycol monomethyl ether acetate, and propylene glycol propyl ether acetate.

[0294] Examples of other organic solvents include 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 ethoxyacetate, 2-hydroxyethyl acetate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, 2-heptanone, methoxycyclopentane, anisole, γ-butyrolactone, N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide.

[0295] Among these solvents (B), alkylene glycol monoalkyl ethers and monocarboxylic acid esters of alkylene glycol monoalkyl ethers are preferred.

[0296] These solvents (B) can be used alone or in combination of two or more.

[0297] The mass ratio of the organic solvent in the solvent (B) is not particularly limited, but is preferably 50% by mass to 100% by mass.

[0298] The content of the solvent (B) in the resist underlayer film-forming composition is not particularly limited, but is preferably 50% by mass to 99.99% by mass, more preferably 75% by mass to 99.95% by mass, and particularly preferably 90% by mass to 99.9% by mass.

[0299] <Crosslinking agent (C)>

[0300] There are no particular restrictions on the cross-linking agent (C).

[0301] The crosslinking agent (C) has a structure different from that of the polymer (A).

[0302] As the crosslinking agent (C), an aminoplast crosslinking agent or a phenoplast crosslinking agent is preferred.

[0303] Aminoplast crosslinking agents are addition condensation products of compounds having amino groups, such as melamine and guanamine, with formaldehyde.

[0304] Phenolic plastic crosslinkers refer to addition condensation products of compounds having phenolic hydroxyl groups and formaldehyde.

[0305] Examples of the cross-linking agent (C) include compounds having two or more of the following structures.

[0306] [Chemistry 57]

[0307]

[0308] (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. Indicates a bond.)

[0309] The bonding bond is, for example, a bond to a nitrogen atom, a carbon atom constituting an aromatic hydrocarbon ring, or the like.

[0310] As R 101 , preferably a hydrogen atom, a methyl group, an ethyl group or a group represented by the following structure.

[0311] [Chemistry 58]

[0312]

[0313] (In the structure, R 102 represents a hydrogen atom, a methyl group, or an ethyl group. Indicates a bond.)

[0314] As the crosslinking agent (C), melamine compounds, guanamine compounds, glycoluril compounds, urea compounds, and compounds having a phenolic hydroxyl group are preferred, and these can be used alone or in combination of two or more.

[0315] Examples of the melamine compound include hexamethylolmelamine, hexamethoxymethylmelamine, compounds obtained by methoxymethylating 1 to 6 hydroxymethyl groups of hexamethylolmelamine, or mixtures thereof, hexamethoxyethylmelamine, hexaacyloxymethylmelamine, compounds obtained by acyloxymethylating 1 to 6 hydroxymethyl groups of hexamethylolmelamine, or mixtures thereof.

[0316] Examples of the guanamine compound include tetrakishydroxymethylguanamine, tetramethoxymethylguanamine, compounds obtained by methoxymethylating 1 to 4 hydroxymethyl groups of tetrakishydroxymethylguanamine, and mixtures thereof; tetramethoxyethylguanamine, tetraacyloxyguanamine, compounds obtained by acyloxymethylating 1 to 4 hydroxymethyl groups of tetrakishydroxymethylguanamine, and mixtures thereof.

[0317] Examples of the glycoluril compound include tetrakishydroxymethyl glycoluril, tetramethoxy glycoluril, tetramethoxymethyl glycoluril, compounds obtained by methoxymethylating 1 to 4 hydroxymethyl groups of tetrakishydroxymethyl glycoluril, or mixtures thereof, and compounds obtained by acyloxymethylating 1 to 4 hydroxymethyl groups of tetrakishydroxymethyl glycoluril, or mixtures thereof.

[0318] In addition, the glycoluril compound may be, for example, a glycoluril derivative represented by the following formula (1E).

[0319] [Chemistry 59]

[0320]

[0321] (In formula (1E), four R1s each independently represent a methyl group or an ethyl group, and R2 and R3 each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group.)

[0322] Examples of the glycoluril derivative represented by the formula (1E) include compounds represented by the following formulas (1E-1) to (1E-6).

[0323] [Chemistry 60]

[0324]

[0325] The glycoluril derivative represented by formula (1E) can be obtained, for example, by reacting a glycoluril derivative represented by the following formula (2E) with at least one compound represented by the following formula (3d).

[0326] [Chemistry 61]

[0327]

[0328] (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.)

[0329] [Chemistry 62]

[0330]

[0331] (In formula (3d), R1 represents a methyl group or an ethyl group.)

[0332] Examples of the glycoluril derivatives represented by formula (2E) include compounds represented by formulas (2E-1) to (2E-4) below. Furthermore, examples of the compounds represented by formula (3d) include compounds represented by formulas (3d-1) and (3d-2) below.

[0333] [Chemistry 63]

[0334]

[0335] [Chemistry 64]

[0336]

[0337] Examples of the urea compound include tetramethylolurea, tetramethoxymethylurea, a compound obtained by methoxymethylating 1 to 4 methylol groups of tetramethylolurea, a mixture thereof, and tetramethoxyethylurea.

[0338] Examples of the compound having a phenolic hydroxyl group include compounds represented by the following formula (G-1) or formula (G-2).

[0339] [Chemistry 65]

[0340]

[0341] (In formula (G-1) and formula (G-2), Q 1 It represents a single bond or an m1-valent organic group.

[0342] 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 having an alkoxy group having 1 to 10 carbon atoms.

[0343] R 2 and R 5 represent a hydrogen atom or a methyl group, respectively.

[0344] 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.

[0345] n1 represents an integer of 1≤n1≤3, n2 represents an integer of 2≤n2≤5, n3 represents an integer of 0≤n3≤3, n4 represents an integer of 0≤n4≤3, and 3≤(n1+n2+n3+n4)≤6.

[0346] n5 represents an integer of 1≤n5≤3, n6 represents an integer of 1≤n6≤4, n7 represents an integer of 0≤n7≤3, n8 represents an integer of 0≤n8≤3, and 2≤(n5+n6+n7+n8)≤5.

[0347] m1 represents an integer from 2 to 10.)

[0348] Examples of the compound having a phenolic hydroxyl group include compounds represented by the following formula (G-3) or formula (G-4).

[0349] The compound represented by formula (G-1) or formula (G-2) can be obtained by reacting a compound represented by the following formula (G-3) or formula (G-4) with a hydroxyl group-containing ether compound or an alcohol having 2 to 10 carbon atoms.

[0350] [Chemistry 66]

[0351]

[0352] (In formula (G-3) and formula (G-4), Q 2 It represents a single bond or an m2-valent organic group.

[0353] R 8 、R 9 、R 11 and R 12 represent a hydrogen atom or a methyl group, respectively.

[0354] 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.

[0355] n9 represents an integer of 1≤n9≤3, n 10 Indicates 2≤n 10 Integer ≤ 5, n 11 Indicates 0≤n 11 Integer ≤ 3, n 12 Indicates 0≤n12 An integer ≤3, and 3≤(n9+n 10 +n 11 +n 12 )≤6.

[0356] n 13 Indicates 1≤n 13 Integer ≤ 3, n 14 Indicates 1≤n 14 Integer ≤ 4, n 15 Indicates 0≤n 15 Integer ≤ 3, n 16 Indicates 0≤n 16 An integer ≤3, and 2≤(n 13 +n 14 +n 15 +n 16 )≤5.

[0357] m2 represents an integer from 2 to 10.)

[0358] As Q 2 Examples of the m2-valent organic group include m2-valent organic groups having 1 to 4 carbon atoms.

[0359] Examples of the compound represented by formula (G-1) or formula (G-2) include the following compounds.

[0360] [Chemistry 67]

[0361]

[0362] [Chemistry 68]

[0363]

[0364] [Chemistry 69]

[0365]

[0366] [Chemistry 70]

[0367]

[0368] [Chemistry 71]

[0369]

[0370] Examples of the compound represented by formula (G-3) or formula (G-4) include the following compounds.

[0371] [Chemistry 72]

[0372]

[0373] [Chemistry 73]

[0374]

[0375] The above compounds can be obtained as products of Asahi Organic Chemicals Industries, Ltd. and Honshu Chemical Industry Co., Ltd. As an example of the product, there is TMOM-BP, a trade name of Asahi Organic Chemicals Industries, Ltd.

[0376] Among them, glycoluril compounds are preferred, specifically, tetrakishydroxymethyl glycoluril, tetramethoxy glycoluril, tetramethoxymethyl glycoluril, compounds obtained by methoxymethylating 1 to 4 hydroxymethyl groups of tetrakishydroxymethyl glycoluril or mixtures thereof, compounds obtained by acyloxymethylating 1 to 4 hydroxymethyl groups of tetrakishydroxymethyl glycoluril or mixtures thereof, and tetramethoxymethyl glycoluril is more preferred.

[0377] The molecular weight of the cross-linking agent (C) is not particularly limited, but is preferably 500 or less.

[0378] The content of the crosslinking agent (C) in the resist underlayer film-forming composition is not particularly limited, but is, for example, 1 to 70 mass %, and preferably 5 to 60 mass %, relative to the polymer (A).

[0379] Curing catalyst (D)

[0380] As the curing catalyst (D) contained as an optional component in the resist underlayer film-forming composition, either a thermal acid generator or a photoacid generator can be used, but a thermal acid generator is preferably used.

[0381] Examples of the thermal acid generator include sulfonic acid compounds and carboxylic acid compounds such as p-toluenesulfonic acid, trifluoromethanesulfonic acid, pyridinium-p-toluenesulfonic acid salt (pyridinium-p-toluenesulfonic acid), pyridinium-phenolsulfonic acid, pyridinium-p-hydroxybenzenesulfonic acid (pyridinium p-phenolsulfonic acid salt), pyridinium-trifluoromethanesulfonic acid, salicylic acid, camphorsulfonic acid, 5-sulfosalicylic acid, 4-chlorobenzenesulfonic acid, 4-hydroxybenzenesulfonic acid, benzenedisulfonic acid, 1-naphthalenesulfonic acid, citric acid, benzoic acid, hydroxybenzoic acid, N-methylmorpholine-p-toluenesulfonic acid, N-methylmorpholine-p-hydroxybenzenesulfonic acid, and N-methylmorpholine-5-sulfosalicylic acid.

[0382] Examples of the photoacid generator include onium salt compounds, sulfonyl imide compounds, and disulfonyldiazomethane compounds.

[0383] Examples of the onium salt compound include iodonium salt compounds such as diphenyliodonium hexafluorophosphate, diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoro-n-butanesulfonate, diphenyliodonium perfluoro-n-octanesulfonate, diphenyliodonium camphorsulfonate, bis(4-tert-butylphenyl)iodonium camphorsulfonate, and bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate; and sulfonium salt compounds such as triphenylsulfonium hexafluoroantimonate, triphenylsulfonium nonafluoro-n-butanesulfonate, triphenylsulfonium camphorsulfonate, and triphenylsulfonium trifluoromethanesulfonate.

[0384] Examples of the sulfonyl imide compound include N-(trifluoromethanesulfonyloxy)succinimide, N-(nonafluoro-n-butanesulfonyloxy)succinimide, N-(camphorsulfonyloxy)succinimide, and N-(trifluoromethanesulfonyloxy)naphthalimide.

[0385] Examples of the disulfonyldiazomethane compound include bis(trifluoromethylsulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, bis(phenylsulfonyl)diazomethane, bis(p-toluenesulfonyl)diazomethane, bis(2,4-dimethylbenzenesulfonyl)diazomethane, and methylsulfonyl-p-toluenesulfonyldiazomethane.

[0386] The curing catalyst (D) may be used alone or in combination of two or more.

[0387] When a curing catalyst (D) is used, the content ratio of the curing catalyst (D) relative to the cross-linking agent (C) is, for example, 0.1% by mass to 50% by mass, preferably 1% by mass to 30% by mass.

[0388] <Other ingredients>

[0389] A surfactant may be further added to the resist underlayer film-forming composition in order to prevent the generation of pinholes, streaks, and the like and to further improve coating properties on surface unevenness.

[0390] Examples of the surfactant include linear or branched alkylbenzenesulfonic acid (e.g., dodecylbenzenesulfonic acid), polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, and polyoxyethylene oleyl ether; polyoxyethylene alkylaryl ethers such as polyoxyethylene octylphenol ether and polyoxyethylene nonylphenol ether; polyoxyethylene-polyoxypropylene block copolymers; sorbitan monolaurate, sorbitan monopalmitate, and sorbitol. Sorbitan fatty acid esters such as sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, and sorbitan tristearate; nonionic surfactants such as polyoxyethylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, and polyoxyethylene sorbitan tristearate; EFTOP Fluorochemical surfactants such as EF301, EF303, and EF352 (trade names of Tochem Products Co., Ltd.), Megafac F171, F173, and R-30 (trade names of DIC Corporation), Fluorad FC430 and FC431 (trade names of Sumitomo 3M Co., Ltd.), AsahiGuard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, and SC106 (trade names of AGC Corporation), and organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.).

[0391] The amount of these surfactants added is usually 2.0% by mass or less, and preferably 1.0% by mass or less, based on the total solid content of the resist underlayer film-forming composition.

[0392] These surfactants may be added alone or in combination of two or more.

[0393] The resist underlayer film-forming composition of the present invention contains a solid content, that is, components other than the solvent, of, for example, 0.01% by mass to 10% by mass.

[0394] (Resist underlayer film)

[0395] The resist underlayer of the present invention is a cured product of the above-mentioned resist underlayer film-forming composition.

[0396] The resist underlayer film can be produced, for example, by applying the above-mentioned resist underlayer film-forming composition on a semiconductor substrate and firing the composition.

[0397] Examples of the semiconductor substrate to which the resist underlayer film-forming composition is applied include silicon wafers, germanium wafers, and compound semiconductor wafers such as gallium arsenide, indium phosphide, gallium nitride, indium nitride, and aluminum nitride.

[0398] When using a semiconductor substrate having 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 (spin-on glass: SOG). Examples of the inorganic film include polysilicon films, silicon oxide films, silicon nitride films, BPSG (borophosphosilicate glass) films, titanium nitride films, titanium oxynitride films, tungsten films, gallium nitride films, and gallium arsenide films.

[0399] The resist underlayer film-forming composition of the present invention is applied to such a semiconductor substrate using an appropriate coating method such as a spin coater or a coater. The resist underlayer film is then baked using a heating means such as a hot plate to form the resist underlayer film. Baking conditions can be appropriately selected from a baking temperature of 100° C. to 400° C. and a baking time of 0.3 to 60 minutes. Preferably, the baking temperature is 120° C. to 350° C. and the baking time is 0.5 to 30 minutes. More preferably, the baking temperature is 150° C. to 300° C. and the baking time is 0.8 to 10 minutes.

[0400] The thickness of the resist underlayer 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 (50 nm), and 0.006 μm (5 nm) to 0.05 μm (50 nm). 0 nm), 0.003 μm (3 nm) to 0.03 μm (30 nm), 0.003 μm (3 nm) to 0.02 μm (20 nm), 0.005 μm (5 nm) to 0.02 μm (20 nm), 0.005 μm (5 nm) to 0.02 μm (20 nm), 0.003 μm (3 nm) to 0.01 μm (10 nm), 0.005 μm (5 nm) to 0.01 μm (10 nm), 0.003 μm (3 nm) to 0.006 μm (6 nm), or 0.005 μm (5 nm). The lower limit of the film thickness is, for example, 0.5 nm, 1 nm, 2 nm, 3 nm, 4 nm, or 5 nm. The upper limit is, for example, 20 nm, 19 nm, 18 nm, 17 nm, 16 nm, 15 nm, 14 nm, 13 nm, 12 nm, 11 nm, 10 nm, 9 nm, 8 nm, 7 nm, 6 nm, 5 nm, 4 nm, 3 nm, or 2 nm.

[0401] The method for measuring the film thickness of the resist underlayer film in this specification is as follows.

[0402] Measurement device: Ellipsometer RE-3100 (SCREEN Co., Ltd.)

[0403] SWE (single wavelength ellipsometer) mode

[0404] Arithmetic average of 8 points (e.g., 8 points measured at 1 cm intervals in the X direction of the wafer)

[0405] (Laminated body)

[0406] The laminated body of the present invention includes a semiconductor substrate and the resist underlayer film of the present invention.

[0407] As the semiconductor substrate, for example, the above-mentioned semiconductor substrates can be mentioned.

[0408] The resist underlayer film is disposed on, for example, a semiconductor substrate.

[0409] (Semiconductor element manufacturing method, pattern forming method)

[0410] The method for manufacturing a semiconductor device of the present invention includes at least the following steps.

[0411] a step of forming a resist underlayer film on a semiconductor substrate using the resist underlayer film-forming composition of the present invention; and

[0412] ・Step of forming a resist film on a resist underlayer film

[0413] The pattern forming method of the present invention includes at least the following steps.

[0414] A step of forming a resist underlayer film on a semiconductor substrate using the resist underlayer film-forming composition of the present invention;

[0415] A step of forming a resist film on the resist underlayer film;

[0416] A step of irradiating the resist film with light or an electron beam and then developing the resist film to obtain a resist pattern; and

[0417] ・The process of etching the resist underlayer film using the resist pattern as a mask

[0418] Usually, a resist layer is formed on the resist underlayer film.

[0419] The thickness of the resist layer is, for example, 3000 nm or less, 2000 nm or less, 1800 nm or less, 1500 nm or less, or 1000 nm or less, and the lower limit is 100 nm, 80 nm, 50 nm, 30 nm, 20 nm, or 10 nm.

[0420] The resist film formed on the resist underlayer film by a known method (e.g., coating and firing a resist composition) is not particularly limited as long as it responds to the light or electron beam (EB) used for irradiation. Both negative-type and positive-type photoresists can be used.

[0421] In addition, in this specification, the resist responsive to EB is also referred to as a photoresist.

[0422] Examples of photoresists include positive-type photoresists containing a novolac resin and 1,2-naphthoquinonediazidesulfonic acid ester, chemically amplified photoresists containing a binder having a group whose alkali dissolution rate increases when decomposed by acid and a photoacid generator, chemically amplified photoresists containing a low molecular weight compound whose alkali dissolution rate increases when decomposed by acid, an alkali-soluble binder, and a photoacid generator, chemically amplified photoresists containing a binder having a group whose alkali dissolution rate increases when decomposed by acid, a low molecular weight compound whose alkali dissolution rate increases when decomposed by acid, and a photoacid generator, and resists containing metal elements. For example, there are V146G manufactured by JSR Corporation, APEX-E manufactured by Shipley, PAR710 manufactured by Sumitomo Chemical Co., Ltd., and AR2772 and SEPR430 manufactured by Shin-Etsu Chemical Co., Ltd. Also, there are fluorine-containing polymer photoresists such as those described in Proc. SPIE, Vol. 3999, 330-334 (2000), Proc. SPIE, Vol. 3999, 357-364 (2000), and Proc. SPIE, Vol. 3999, 365-374 (2000).

[0423] In addition, 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 This special issue 2016-035567, Japan’s special issue 2016-035565, Japan’s special issue 2019-101417, Japan’s special issue 2019-117373 , Japanese 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 2019-0 61217, Japanese 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 20 11-043749, Japanese Patent Application Laid-Open No. 2010-181857, Japanese Patent Application Laid-Open No. 2010-128369, WO2018 / 031896, Japanese Patent Application Laid-Open No. 2019-113855, WO2017 / 156388, WO2017 / 066319, Japanese Patent Application Laid-Open No. 2018-41099, WO2016 / 065120, WO2015 / 026482, Japanese Patent Application Laid-Open No. 2016-29498, Japanese Patent Application Laid-Open No. 2011-253185, etc., so-called resist compositions, such as radiation-sensitive resin compositions, high-resolution patterning compositions based on organic metal solutions, and metal-containing resist compositions, but are not limited to these.

[0424] Examples of the resist composition include the following compositions.

[0425] An active light ray-sensitive or radiation-sensitive resin composition comprises a resin A and a compound represented by the following general formula (121), wherein the resin A has a repeating unit having an acid-decomposable group, the polar group of the acid-decomposable group is protected by a protecting group, and the protecting group is detached by the action of an acid.

[0426] [Chemistry 74]

[0427]

[0428] In the general formula (121), m represents an integer of 1 to 6.

[0429] R1 and R2 each independently represent a fluorine atom or a perfluoroalkyl group.

[0430] L1 represents -O-, -S-, -COO-, -SO2-, or -SO3-.

[0431] L2 represents an alkylene group which may have a substituent or a single bond.

[0432] W1 represents a cyclic organic group which may have a substituent.

[0433] M + Represents a cation.

[0434] A metal-containing film-forming composition for extreme ultraviolet or electron beam lithography comprises a compound having a metal-oxygen covalent bond and a solvent, wherein the metal element constituting the compound belongs to the third to seventh periods of the third to fifteenth groups of the periodic table.

[0435] A radiation-sensitive resin composition contains a polymer and an acid generator, wherein the polymer has a first structural unit represented by the following formula (31) and a second structural unit containing an acid-dissociable group represented by the following formula (32).

[0436] [Chemistry 75]

[0437]

[0438] (In formula (31), Ar is a group obtained by removing (n+1) hydrogen atoms from an aromatic hydrocarbon having 6 to 20 carbon atoms. R 1 is a hydroxyl group, a mercapto group, or a monovalent organic group having 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. 2 is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. 3It is a monovalent group having 1 to 20 carbon atoms and containing the above-mentioned acid-dissociable group. Z is a single bond, an oxygen atom or a sulfur atom. 4 is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group.)

[0439] A resist composition comprises a resin (A1) and an acid generator, wherein the resin (A1) comprises a structural unit having a cyclic carbonate structure, a structural unit represented by the following formula, and a structural unit having an acid-labile group.

[0440] [Chemistry 76]

[0441]

[0442] [Where,

[0443] R 2 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom, and X 1 Indicates a single key, or , Represents the bond with -Ar, R 4 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have one or more groups selected from hydroxyl groups and carboxyl groups.]

[0444] Examples of the resist film include the following.

[0445] A resist film includes a base resin comprising a repeating unit represented by the following formula (a1) and / or a repeating unit represented by the following formula (a2), and a repeating unit that generates an acid and bonds to a polymer main chain upon exposure.

[0446] [Chemistry 77]

[0447]

[0448] (In formula (a1) and formula (a2), R A R are each independently a hydrogen atom or a methyl group. 1 and R 2 Each independently represents a tertiary alkyl group having 4 to 6 carbon atoms. 3 Each independently represents a fluorine atom or a methyl group. m represents an integer from 0 to 4. 1 X is a single bond, a phenylene group, a naphthylene group, or a linking group having 1 to 12 carbon atoms and containing at least one selected from an ester bond, a lactone ring, a phenylene group, and a naphthylene group. 2 is a single bond, an ester bond, or an amide bond.)

[0449] Examples of resist materials include the following.

[0450] A resist material comprising a polymer having a repeating unit represented by the following formula (b1) or formula (b2).

[0451] [Chemistry 78]

[0452]

[0453] (In formula (b1) and formula (b2), R A X is a hydrogen atom or a methyl group. 1 Is a single bond or an ester group. 2 is a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms or an arylene group having 6 to 10 carbon atoms, wherein a portion of the methylene groups constituting the alkylene group may be substituted with an ether group, an ester group or a group containing a lactone ring, and further, X 2 At least one hydrogen atom contained in X may be replaced by a bromine atom. 3 It is a single bond, an ether group, an ester group, or a linear, branched, or cyclic alkylene group having 1 to 12 carbon atoms, and a portion of the methylene groups constituting the alkylene group may be substituted with an ether group or an ester group. 1 ~Rf 4 Each independently represents a hydrogen atom, a fluorine atom or a trifluoromethyl group, but at least one of them is a fluorine atom or a trifluoromethyl group. 1 and Rf 2 Can combine to form a carbonyl group. 1 ~R 5 Each is independently a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms, a linear, branched or cyclic alkenyl group having 2 to 12 carbon atoms, an alkynyl group having 2 to 12 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or an aryloxyalkyl group having 7 to 12 carbon atoms, and some or all of the hydrogen atoms in these groups may be replaced by hydroxyl groups, carboxyl groups, halogen atoms, oxo groups, cyano groups, amide groups, nitro groups, sultone groups, sulfo groups or groups containing sulfonium salts, and some of the methylene groups constituting these groups may be replaced by ether groups, ester groups, carbonyl groups, carbonate groups or sulfonate groups. In addition, R 1 and R 2 can bond to form a ring together with the sulfur atom to which they are bonded.)

[0454] A resist material includes a base resin containing a polymer having a repeating unit represented by the following formula (a).

[0455] [Chemistry 79]

[0456]

[0457] (In formula (a), R A is a hydrogen atom or a methyl group. 1is a hydrogen atom or an acid-labile group. 2 is a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, or a halogen atom other than bromine. 1 X is a single bond or a phenylene group, or a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms which may contain an ester group or a lactone ring. 2 is -O-, -O-CH2-, or -NH-. m is an integer from 1 to 4. u is an integer from 0 to 3. Wherein, m+u is an integer from 1 to 4.

[0458] A resist composition that generates acid upon exposure and changes its solubility in a developer by the action of the acid.

[0459] Contains a base component (A) whose solubility in a developer changes due to the action of an acid and a fluorine additive component (F) that is decomposable in an alkaline developer.

[0460] The fluorine additive component (F) contains a fluororesin component (F1) having a structural unit (f1) containing an alkali-dissociable group and a structural unit (f2) containing a group represented by the following general formula (f2-r-1).

[0461] [Chemistry 80]

[0462]

[0463] [In formula (f2-r-1), Rf 21 Each is independently a hydrogen atom, an alkyl group, an alkoxy group, a hydroxyl group, a hydroxyalkyl group or a cyano group. n'' is an integer of 0 to 2. is a bonding key.]

[0464] The structural unit (f1) includes a structural unit represented by the following general formula (f1-1) or a structural unit represented by the following general formula (f1-2).

[0465] [Chemistry 81]

[0466]

[0467] [In formulas (f1-1) and (f1-2), R is independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. X is a divalent linking group having no acid-dissociable site. A aryl is a divalent aromatic cyclic group which may have a substituent. 01 is a single bond or a divalent linking group. 2 Each independently represents an organic group having a fluorine atom.]

[0468] Examples of the coating layer, coating solution, and coating composition include the following.

[0469] A coating comprising a metal oxo-hydroxo network having organic ligands via metal-carbon bonds and / or metal-carboxylate bonds.

[0470] Inorganic oxygen / hydroxyl matrix combination.

[0471] A coating solution, which is a coating solution, comprises: an organic solvent, a first organic metal composition, and a hydrolyzable metal compound, wherein the first organic metal composition is represented by the formula R z SnO (2-(z / 2)-(x / 2)) (OH) x (where 0<z≤2 and 0<(z+x)≤4), formula R′ n SnX 4-n (wherein n=1 or 2) or a mixture thereof, wherein R and R′ are independently a hydrocarbon group having 1 to 31 carbon atoms, and X is a ligand having a hydrolyzable bond to Sn or a combination thereof; the hydrolyzable metal compound is represented by the formula MX′ v (wherein, 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 having a hydrolyzable MX bond or a combination thereof).

[0472] A coating solution comprising an organic solvent and a compound of formula RSnO （3 / 2-x / 2） (OH) x A coating solution of a first organometallic compound represented by (wherein 0<x<3) contains about 0.0025M to about 1.5M 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 the tin on a secondary or tertiary carbon atom.

[0473] An inorganic pattern forming precursor aqueous solution is a mixture containing water, metal suboxide cations, polyatomic inorganic anions, and a radiation-sensitive ligand containing a peroxide group.

[0474] Irradiation with light or electron beams is performed, for example, through a mask (reticle) for forming a predetermined pattern. Examples of such applications include i-rays, KrF excimer lasers, ArF excimer lasers, EUV (extreme ultraviolet light), or EB (electron beam). The resist underlayer film-forming composition of the present invention is preferably used for EB (electron beam) or EUV (extreme ultraviolet light: 13.5 nm) irradiation, and more preferably for EUV (extreme ultraviolet light) exposure.

[0475] There are no particular restrictions on the irradiation energy of the electron beam and the exposure dose of light.

[0476] Post-exposure bake (PEB) is performed after irradiation with light or electron beams and before development.

[0477] The baking temperature is not particularly limited, but is preferably 60°C to 150°C, more preferably 70°C to 120°C, and particularly preferably 75°C to 110°C.

[0478] The baking time is not particularly limited, but is preferably 1 second to 10 minutes, more preferably 10 seconds to 5 minutes, and particularly preferably 30 seconds to 3 minutes.

[0479] For development, for example, an alkaline developer is used.

[0480] As an example of the development temperature, 5°C to 50°C can be mentioned.

[0481] As a development time, 10 seconds - 300 seconds are mentioned, for example.

[0482] As an alkaline developer, for example, inorganic bases such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and ammonia water, primary amines such as ethylamine and n-propylamine, secondary amines such as diethylamine and di-n-butylamine, tertiary amines such as triethylamine and methyldiethylamine, alcohol amines such as dimethylethanolamine and triethanolamine, quaternary ammonium salts such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, and choline, and aqueous solutions of alkalis such as cyclic amines such as pyrrole and piperidine can be used. In addition, an appropriate amount of an alcohol such as isopropyl alcohol or a nonionic surfactant can be added to the aqueous solution of the above-mentioned alkalis. Among them, a preferred developer is an aqueous solution of a quaternary ammonium salt, and an aqueous solution of tetramethylammonium hydroxide and an aqueous solution of choline are more preferred. Moreover, a surfactant can also be added to these developers. Alternatively, the following method can be used: instead of an alkaline developer, an organic solvent such as butyl acetate is used for development, and the portion of the photoresist whose alkali dissolution rate is not increased is developed.

[0483] Next, the resist underlayer film is etched using the formed resist pattern as a mask. The etching may be dry etching or wet etching, but dry etching is preferred.

[0484] If the inorganic film is formed on the surface of the semiconductor substrate being used, the surface of the inorganic film is exposed. If the inorganic film is not formed on the surface of the semiconductor substrate being used, the surface of the semiconductor substrate is exposed. Subsequently, the semiconductor substrate is processed using a known method (such as dry etching) to manufacture a semiconductor device.

[0485] Example

[0486] Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.

[0487] The weight average molecular weight (Mw) of the polymers shown in the following synthesis examples is the result of measurement by gel permeation chromatography (GPC). A GPC apparatus manufactured by Tosoh Corporation was used for the measurement, and the measurement conditions were as follows.

[0488] Measuring device: HLC-8020GPC [trade name] (manufactured by Tosoh Corporation)

[0489] GPC columns: TSKgel G2000HXL (2), G3000HXL (1), G4000HXL (1) [Trade Name] (all manufactured by Tosoh Corporation)

[0490] Column temperature: 40°C

[0491] Solvent: Tetrahydrofuran (THF)

[0492] Flow rate: 1.0ml / min

[0493] Standard sample: Polystyrene (manufactured by Tosoh Corporation)

[0494] <Synthesis Example 1> Synthesis of Polymer 1

[0495] 4.54 g of monoallyl diglycidyl isocyanuric acid, 5.19 g of 2-iodoisophthalic acid, and 0.27 g of tetrabutylphosphonium bromide were added to 40.00 g of propylene glycol monomethyl ether in a reaction vessel and dissolved. After nitrogen was purged in the reaction vessel, the mixture was heated under reflux for 24 hours to obtain a solution of Polymer 1. GPC analysis revealed that the weight average molecular weight of Polymer 1 in the obtained solution was 4700 in terms of standard polystyrene.

[0496] The repeating units of the obtained polymer 1 are shown below. In the figure, n is the number of repeating units (the same applies hereinafter).

[0497] [Chemistry 82]

[0498]

[0499] <Synthesis Example 2> Synthesis of Polymer 2

[0500] 4.68 g of monoallyl diglycidyl isocyanuric acid, 4.14 g of 2-iodoisophthalic acid, 0.90 g of adamantane carboxylic acid, and 0.28 g of tetrabutylphosphonium bromide were added to 40.00 g of propylene glycol monomethyl ether in a reaction vessel and dissolved. After nitrogen was purged in the reaction vessel, the mixture was heated under reflux for 24 hours to obtain a solution of Polymer 2. GPC analysis revealed that the weight average molecular weight of Polymer 2 in the obtained solution was 8000 in terms of standard polystyrene.

[0501] The repeating units of the obtained polymer 2 are shown below. The terminal structures are also described in the following structures.

[0502] [Chemistry 83]

[0503]

[0504] <Synthesis Example 3> Synthesis of Polymer 3

[0505] 4.23 g of monoallyl diglycidyl isocyanuric acid, 3.75 g of 2-iodoisophthalic acid, 1.76 g of 3,5-diiodosalicylic acid, and 0.26 g of tetrabutylphosphonium bromide were added to 40.00 g of propylene glycol monomethyl ether in a reaction vessel and dissolved. After nitrogen was purged in the reaction vessel, the mixture was heated under reflux for 24 hours to obtain a solution of polymer 3. GPC analysis revealed that the weight average molecular weight of polymer 3 in the obtained solution was 7300 in terms of standard polystyrene.

[0506] The repeating units of the obtained polymer 3 are shown below. The terminal structures are also described in the following structures.

[0507] [Chemistry 84]

[0508]

[0509] <Synthesis Example 4> Synthesis of Polymer 4

[0510] 3.99 g of monomethyl diglycidyl isocyanuric acid, 5.74 g of 2-iodoisophthalic acid, and 0.28 g of tetrabutylphosphonium bromide were added to 40.00 g of propylene glycol monomethyl ether in a reaction vessel and dissolved. After the reaction vessel was purged with nitrogen, the mixture was heated under reflux and reacted for 24 hours to obtain a solution of polymer 4. GPC analysis revealed that the weight average molecular weight of polymer 4 in the obtained solution was 3500 in terms of standard polystyrene.

[0511] The repeating units of the obtained polymer 4 are shown below.

[0512] [Chemistry 85]

[0513]

[0514] <Synthesis Example 5> Synthesis of Polymer 5

[0515] 4.41 g of diglycidyl terephthalate (manufactured by Nagase ChemteX Co., Ltd., trade name: Denacol [registered trademark] EX711), 5.33 g of 2-iodoisophthalic acid, and 0.26 g of tetrabutylphosphonium bromide were added to 40.00 g of propylene glycol monomethyl ether in a reaction vessel and dissolved. After nitrogen was purged in the reaction vessel, the mixture was heated under reflux and reacted for 24 hours to obtain a solution of Polymer 5. GPC analysis revealed that the weight average molecular weight of Polymer 5 in the resulting solution was 3700 in terms of standard polystyrene.

[0516] The repeating units of the obtained polymer 5 are shown below.

[0517] [Chemistry 86]

[0518]

[0519] <Synthesis Example 6> Synthesis of Polymer 6

[0520] 4.89 g of monoallyl diglycidyl isocyanuric acid, 4.96 g of 5-iodouracil, and 0.15 g of tetrabutylphosphonium bromide were added to 40.00 g of cyclohexanone in a reaction vessel and dissolved. After nitrogen purge, the reaction was allowed to proceed at 120°C for 24 hours to obtain a solution of polymer 6. GPC analysis revealed that the weight average molecular weight of polymer 6 in the solution was 2300 in terms of standard polystyrene.

[0521] The repeating units of the obtained polymer 6 are shown below.

[0522] [Chemistry 87]

[0523]

[0524] <Comparative Synthesis Example 1> Synthesis of Comparative Polymer 1

[0525] 8.00 g of monoallyl diglycidyl isocyanuric acid, 5.45 g of barbital, and 0.48 g of tetrabutylphosphonium bromide were added to 56.00 g of propylene glycol monomethyl ether in a reaction vessel and dissolved. After nitrogen was purged in the reaction vessel, the mixture was heated under reflux for 24 hours to obtain a solution of Comparative Polymer 1. GPC analysis revealed that the weight average molecular weight of Comparative Polymer 1 in the obtained solution was 6800 in terms of standard polystyrene.

[0526] The repeating units of the obtained comparative polymer 1 are shown below.

[0527] [Chemistry 88]

[0528]

[0529] <Comparative Synthesis Example 2> Synthesis of Comparative Polymer 2

[0530] 5.65 g of monoallyl diglycidyl isocyanuric acid, 4.07 g of isophthalic acid, and 0.34 g of tetrabutylphosphonium bromide were added to 40.00 g of propylene glycol monomethyl ether in a reaction vessel and dissolved. After the reaction vessel was purged with nitrogen, the mixture was heated under reflux for 24 hours to obtain a solution of Comparative Polymer 2. GPC analysis revealed that the weight average molecular weight of Comparative Polymer 2 in the obtained solution was 5300 in terms of standard polystyrene.

[0531] The repeating units of the obtained comparative polymer 2 are shown below.

[0532] [Chemistry 89]

[0533]

[0534] (Preparation of Resist Underlayer Film-Forming Composition)

[0535] The polymers obtained in the above synthesis examples were mixed with additives and solvents in the ratios shown in Table 1-1 or Table 1-2, and filtered using a polyethylene microfilter with a pore size of 0.05 μm to prepare resist underlayer film-forming compositions.

[0536] In addition, in Example 1-1 of Table 1-1, 1.600 parts by mass of component 1 means that polymer 1 is 1.600 parts by mass.

[0537] The abbreviations in Tables 1-1 and 1-2 are as follows.

[0538] PL-LI: Tetramethoxymethyl glycoluril

[0539] ·PyPTS:Pyridinium-toluenesulfonic acid

[0540] PGMEA: Propylene glycol monomethyl ether acetate

[0541] PGME: Propylene glycol monomethyl ether

[0542] CY: Cyclohexanone

[0543] [Table 1-1]

[0544]

[0545] [Table 1-2]

[0546]

[0547] (Determination of dry etching rate)

[0548] The following etcher and etching gas were used for the measurement of the dry etching rate.

[0549] RIE-10NR (Samco): CF4

[0550] The resist underlayer film-forming compositions of Examples 1-1 to 6-1 and Comparative Examples 1-1 to 2-1 were each applied onto a silicon wafer using a spin coater. The silicon wafer was baked on a hot plate at 215°C for 60 seconds to form a resist underlayer film (film thickness 500 nm). The film thickness was measured using an ellipsometer RE-3100 (SCREEN Co., Ltd.).

[0551] The dry etching rates of these resist underlayer films were measured using CF4 gas as etching gas. Table 2 shows the etching rate ratios when the etching rate of the resist underlayer film of Comparative Example 1-1 is set to 1.0.

[0552] [Table 2]

[0553]

[0554] (Resist Patterning Evaluation)

[0555] <Resist Pattern Formation Test Using Electron Beam Lithography Equipment>

[0556] The resist underlayer film-forming compositions of Examples 1-2 to 6-2 and Comparative Examples 1-2 to 2-2 were applied onto silicon wafers using a spin coater and baked on a hot plate at 215° C. for 60 seconds to form resist underlayer films (500 nm thick).

[0557] A positive-tone EUV resist solution was spin-coated onto each resist underlayer film formed on a silicon wafer and heated at 130°C for 60 seconds to form a 35nm-thick EUV resist film. The resist film was exposed under specified conditions using an electron beam lithography system (ELS-G130). After exposure, the film was baked (PEB) at 90°C for 60 seconds, cooled to room temperature on a cooling plate, and then developed using a 2.38% tetramethylammonium hydroxide aqueous solution (NMD-3, manufactured by Tokyo Ohka Kogyo Co., Ltd.) as a photoresist developer for 30 seconds using a puddle developing method. This formed a resist pattern with line dimensions of 16nm to 28nm. The resist pattern was measured using a scanning electron microscope (CG4100, manufactured by Hitachi High-Technologies Corporation).

[0558] The photoresist pattern thus obtained was observed from the top of the pattern, and the charge amount that formed 22 nm lines / 44 nm spaces (line and space (L / S = 1 / 1)) was defined as the optimal irradiation energy. The irradiation energy at this time (μC / cm 2 ), and LWR (Line Width Roughness), a value representing the roughness of the pattern shape. LWR represents three times the standard deviation (σ) (unit: nm) of the measurement results obtained using a scanning electron microscope (manufactured by Hitachi High-Technologies Corporation, CG4100) at 400 positions along the length of the line. A smaller LWR value indicates a more favorable pattern. The results are shown in Table 3.

[0559] [Table 3]

[0560]

[0561] As shown in Table 2, Examples 1-1 to 6-1 demonstrated improved etching rates compared to Comparative Examples 1-1 and 2-1. Table 3 shows that Examples 1-2 to 6-2 exhibited comparable lithographic properties to Comparative Examples 1-2 and 2-2. Thus, the resist underlayer film-forming compositions using polymers 1 to 6 were able to accelerate etching rates while maintaining lithographic properties.

Claims

1. A resist underlayer film-forming composition, characterized in that: Containing a polymer (A) having a repeating unit represented by the following formula (1) and a solvent (B), ， In formula (1), X 1 represents a divalent group having a ring structure and an iodine atom directly bonded to the ring structure, X 2 represents a divalent group, A 1 、A 2 、A 3 、A 4 、A 5 and A 6 Each independently represents a hydrogen atom, a methyl group or an ethyl group.

2. The resist underlayer film-forming composition according to claim 1, wherein X in the formula (1) 1 represents any one of a group represented by the following formula (2-1), a group represented by the following formula (2-2), and a group represented by the following formula (2-3), ， In formula (2-1), Q 1 represents a divalent organic group represented by the following formula (2-1-1), a divalent organic group represented by the following formula (2-1-2), a divalent organic group represented by the following formula (2-1-3), or a divalent organic group represented by the following formula (2-1-4), n1 and n2 each independently represent 0 or 1, Indicates a bond, In formula (2-2), R 1 represents a hydrogen atom, a halogen atom, or an organic group having 1 to 10 carbon atoms, Indicates a bond, In formula (2-3), R 2 represents a hydrogen atom, a halogen atom, or an organic group having 1 to 10 carbon atoms, Indicates a bond, ， In formulas (2-1-1) to (2-1-4), R 11 ~R 16 Each independently represents a halogen atom, a hydroxyl group, a cyano group, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkenyloxy group having 2 to 6 carbon atoms, an alkynyloxy group having 2 to 6 carbon atoms, an acyl group having 2 to 6 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, an arylcarbonyl group having 7 to 13 carbon atoms, an aralkyl group having 7 to 13 carbon atoms, or -N(R a )(R b ), represents a bond, wherein the halogen atoms do not include iodine atoms, R a and R b each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, In formula (2-1-1), p11 represents an integer from 0 to 2. When p11 is 0, m11 represents an integer from 1 to 4, n11 represents an integer from 0 to 3, and the total of m11 and n11 is 4 or less. When p11 is 1, m11 represents an integer from 1 to 6, n11 represents an integer from 0 to 5, and the total of m11 and n11 is 6 or less. When p11 is 2, m11 represents an integer from 1 to 8, n11 represents an integer from 0 to 7, and the total of m11 and n11 is 8 or less. 11 When there are 2 or more, 2 or more R 11 Same or different, In formula (2-1-2), Z 11 represents a single bond, an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or an alkylene group having 1 to 6 carbon atoms, m12 and m13 each independently represent an integer of 0 to 4, n12 and n13 each independently represent an integer of 0 to 4, the total of m12 and m13 is 1 or more, the total of m12 and n12 is 4 or less, the total of m13 and n13 is 4 or less, and in R 12 When there are 2 or more, 2 or more R 12 Same or different, in R 13 When there are 2 or more, 2 or more R 13 Same or different, In formula (2-1-3), Z 12 and Z 13 Each independently represents a single bond, or a linear or branched alkylene group having 1 to 6 carbon atoms, m14 represents an integer of 1 to 4, n14 represents an integer of 0 to 3, and the total of m14 and n14 is 4 or less. 14 When there are 2 or more, 2 or more R 14 Same or different, In formula (2-1-4), Z 14 represents a single bond, an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or an alkylene group having 1 to 6 carbon atoms, and Z 15 and Z 16 Each independently represents a single bond, or a linear or branched alkylene group having 1 to 6 carbon atoms, m15 and m16 each independently represent an integer from 0 to 4, n15 and n16 each independently represent an integer from 0 to 4, the total of m15 and m16 is 1 or more, the total of m15 and n15 is 4 or less, the total of m16 and n16 is 4 or less, and in R 15 When there are 2 or more, 2 or more R 15 Same or different, in R 16 When there are 2 or more, 2 or more R 16 Same or different.

3. The resist underlayer film-forming composition according to claim 1, wherein X in the formula (1) 2 represents any one of a group represented by the following formula (3-1) and a group represented by the following formula (3-2), ， In formula (3-1), Q 11 represents a divalent acyclic hydrocarbon group having 2 to 20 carbon atoms which may be interrupted by oxygen atoms, a divalent organic group represented by the following formula (3-1-1), a divalent organic group represented by the following formula (3-1-2), a divalent organic group represented by the following formula (3-1-3), or a divalent organic group represented by the following formula (3-1-4), wherein n1 and n2 each independently represent 0 or 1, Indicates a bond, In formula (3-2), X 11 represents a divalent group represented by any one of the following formulas (3-2-1) to (3-2-3), Z 1 and Z 2 Each independently represents a single bond or a divalent group represented by the following formula (2-2-4), Indicates a bond, ， In formulas (3-1-1) to (3-1-4), R 21 ~R 26 each independently represents a halogen atom, a hydroxyl group, a cyano group, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkenyloxy group having 2 to 6 carbon atoms, an alkynyloxy group having 2 to 6 carbon atoms, an acyl group having 2 to 6 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, an arylcarbonyl group having 7 to 13 carbon atoms, or an aralkyl group having 7 to 13 carbon atoms, Indicates a bond, In formula (3-1-1), p21 represents an integer from 0 to 2. When p21 is 0, n21 represents an integer from 0 to 4. When p21 is 1, n21 represents an integer from 0 to 6. When p21 is 2, n21 represents an integer from 0 to 8. 21 When there are 2 or more, 2 or more R 21 Same or different, In formula (3-1-2), Z 21 represents a single bond, an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or an alkylene group having 1 to 6 carbon atoms, n22 and n23 each independently represent an integer of 0 to 4, and in R 22 When there are 2 or more, 2 or more R 22 Same or different, in R 23 When there are 2 or more, 2 or more R 23 Same or different, In formula (3-1-3), Z 22 and Z 23 Each independently represents a single bond, or a linear or branched alkylene group having 1 to 6 carbon atoms, n24 represents an integer of 0 to 4, and in R 24 When there are 2 or more, 2 or more R 24 Same or different, In formula (3-1-4), Z 24 represents a single bond, an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or an alkylene group having 1 to 6 carbon atoms, and Z 25 and Z 26 Each independently represents a single bond, or a linear or branched alkylene group having 1 to 6 carbon atoms, n25 and n26 each independently represent an integer from 0 to 4, and in R 25 When there are 2 or more, 2 or more R 25 Same or different, in R 26 When there are 2 or more, 2 or more R 26 Same or different, ， In formulas (3-2-1) to (3-2-3), R 1 ~R 5 Each independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom, an alkenyl group having 2 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom, an alkynyl group having 2 to 10 carbon atoms which may be interrupted by an oxygen atom or a sulfur atom, a benzyl group, or a phenyl group, wherein the phenyl group may be substituted by at least one monovalent group selected from an alkyl group having 1 to 6 carbon atoms, a halogen atom, an alkoxy group having 1 to 6 carbon atoms, a nitro group, a cyano group, and an alkylthio group having 1 to 6 carbon atoms, and R 1 and R 2 bonded to form a ring with 3 to 6 carbon atoms or not, R 3 and R 4 bonded to each other to form a ring with 3 to 6 carbon atoms or not to form a ring, Indicates a bond, 1 represents a bond to the carbon atom in formula (3-2), 2 represents a bond to the nitrogen atom in formula (3-2), ， In formula (3-2-4), m1 is an integer from 0 to 4, m2 is 0 or 1, m3 is 0 or 1, and m4 is an integer from 0 to 2. When m3 is 1, m1 and m2 are not both 0. 3 represents a bond to the nitrogen atom in formula (3-2), 4 represents a bonding bond.

4. The resist underlayer film-forming composition according to claim 1, wherein The solvent (B) contains at least one selected from the group consisting of alkylene glycol monoalkyl ethers and monocarboxylic acid esters of alkylene glycol monoalkyl ethers.

5. The resist underlayer film-forming composition according to claim 1, wherein The resist underlayer film-forming composition further contains a crosslinking agent (C).

6. The resist underlayer film-forming composition according to claim 1, wherein The resist underlayer film-forming composition further contains a curing catalyst (D).

7. A resist underlayer film, characterized in that: A cured product of the resist underlayer film-forming composition according to any one of claims 1 to 6.

8. A laminated body, characterized in that: have: semiconductor substrate; and The resist underlayer film according to claim 7.

9. A method for manufacturing a semiconductor element, characterized in that: Including the following processes: A step of forming a resist underlayer film on a semiconductor substrate using the resist underlayer film-forming composition according to any one of claims 1 to 6; and a step of forming a resist film on the resist underlayer film.

10. A pattern forming method, characterized in that: Including the following processes: A step of forming a resist underlayer film on a semiconductor substrate using the resist underlayer film-forming composition according to any one of claims 1 to 6; forming a resist film on the resist underlayer film; irradiating the resist film with light or an electron beam, and then developing the resist film to obtain a resist pattern; as well as A step of etching the resist underlayer film using the resist pattern as a mask.

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