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US-12624016-B2 - Salt, acid generator, resist composition and method for producing resist pattern

US12624016B2US 12624016 B2US12624016 B2US 12624016B2US-12624016-B2

Abstract

Provided are a salt capable of producing a resist pattern with satisfactory CD Uniformity (CDU), an acid generator, and a resist composition. Disclosed are a salt represented by formula (I), an acid generator, and a resist composition: wherein, in formula (I), R 4 , R 5 , R 6 , R 7 , R 8 and R 9 each represent a halogen atom, a haloalkyl group, etc.; A 1 , A 2 and A 3 each represent a hydrocarbon group, etc.; m1 and m4, m5, m6 and m7 represent an integer of 0 to 5, m2, m3, m8 and m9 represent an integer of 0 to 4, 0≤m1+m7≤5, 0≤m2+m8≤4, 0≤m3+m9≤4, and at least one of m1, m2 and m3 represents an integer of 1 or more; X 4 represents a single bond, —CH 2 —, —O—, —S—, —CO—, —SO— or —SO 2 —; and AI − represents an organic anion.

Inventors

  • Katsuhiro Komuro
  • Jun Oguma
  • Koji Ichikawa

Assignees

  • SUMITOMO CHEMICAL COMPANY, LIMITED

Dates

Publication Date
20260512
Application Date
20220411
Priority Date
20210415

Claims (15)

  1. 1 . A salt represented by formula (I): wherein, in formula (I), R 4 represents a halogen atom, a haloalkyl group having 1 to 12 carbon atoms or a hydrocarbon group having 1 to 18 carbon atoms, the hydrocarbon group optionally has a substituent, and —CH 2 — in the haloalkyl group and the hydrocarbon group is optionally replaced by —O—, —S—, —CO— or —SO 2 —, and the hydrocarbon group is a chain saturated hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group formed by combining two or more of the chain saturated hydrocarbon group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group, R 5 , R 6 , R 7 , R 8 and R 9 each independently represent a halogen atom, a haloalkyl group having 1 to 12 carbon atoms or a hydrocarbon group having 1 to 18 carbon atoms, the hydrocarbon group optionally has a substituent, and —CH 2 — in the haloalkyl group and the hydrocarbon group is optionally replaced by —O—, —S—, —CO— or —SO 2 —, A 1 , A 2 and A 3 each independently represent a hydrocarbon group having 2 to 20 carbon atoms, the hydrocarbon group optionally has a substituent, and one of —CH 2 — in the hydrocarbon group is optionally replaced by —O—, —CO—, —S— or —SO 2 —, m1 represents an integer of 0 to 5, and when m1 is 2 or more, a plurality of groups in parentheses are the same or different from each other, m2 represents an integer of 0 to 4, and when m2 is 2 or more, a plurality of groups in parentheses are the same or different from each other, m3 represents an integer of 0 to 4, and when m3 is 2 or more, a plurality of groups in parentheses are the same or different from each other, m4 represents an integer of 0 to 5, and when m4 is 2 or more, a plurality of R 4 are the same or different from each other, m5 represents an integer of 0 to 5, and when m5 is 2 or more, a plurality of R 5 are the same or different from each other, m6 represents an integer of 0 to 5, and when m6 is 2 or more, a plurality of R 6 are the same or different from each other, m7 represents an integer of 0 to 5, and when m7 is 2 or more, a plurality of R 7 are the same or different from each other, m8 represents an integer of 0 to 4, and when m8 is 2 or more, a plurality of R 8 are the same or different from each other, m9 represents an integer of 0 to 4, and when m9 is 2 or more, a plurality of R 9 are the same or different from each other, in which 0≤m1+m7≤5,0≤m2+m8≤4,0≤m3+m9≤4, and at least one of m1, m2 and m3 represents an integer of 1 or more, X 4 represents a single bond, —CH 2 —, —O—, —S—, —CO—, —SO— or —SO 2 —, and AI − represents a sulfonic acid anion, a sulfonylimide anion, a sulfonylmethide anion or a carboxylic acid anion.
  2. 2 . The salt according to claim 1 , wherein A 1 is *—X 01 -L 01 - or *-L 01 -X 01 —, A 2 is *—X 02 -L 02 - or *-L 02 -X 02 —, and A 3 is *—X 03 -L 03 - or *-L 03 -X 03 — wherein X 01 , X 02 and X 03 each independently represent —O—, —CO—, —S— or —SO 2 —, L 01 , L 02 and L 03 each independently represent a hydrocarbon group having 1 to 19 carbon atoms, the hydrocarbon group optionally has a substituent, and * represents a bonding site to the benzene ring to which R 4 , R 5 or R 6 is optionally bonded.
  3. 3 . The salt according to claim 2 , wherein X 01 , X 02 and X 03 are each independently —O— or —S—.
  4. 4 . The salt according to claim 2 , wherein L 01 , L 02 and L 03 are each independently an alkanediyl group having 1 to 6 carbon atoms.
  5. 5 . The salt according to claim 1 , wherein R 4 , R 5 and R 6 are each independently a fluorine atom, an iodine atom, a perfluoroalkyl group having 1 to 4 carbon atoms or an alkyl group having 1 to 4 carbon atoms and —CH 2 — in the alkyl group is optionally replaced by —O— or —CO—.
  6. 6 . The salt according to claim 1 , wherein R 7 , R 8 and R 9 are each independently a fluorine atom, an iodine atom, a perfluoroalkyl group having 1 to 4 carbon atoms or an alkyl group having 1 to 4 carbon atoms and —CH 2 — in the alkyl group is optionally replaced by —O— or —CO—.
  7. 7 . The salt according to claim 1 , wherein AI − is a sulfonic acid anion, a sulfonylimide anion, or a sulfonylmethide anion.
  8. 8 . The salt according to claim 1 , wherein AI − is a sulfonic acid anion, and the sulfonic acid anion is an anion represented by formula (I-A): wherein, in formula (I-A), Q 1 and Q 2 each independently represent a hydrogen atom, a fluorine atom, an alkyl group having 1 to 6 carbon atoms or a perfluoroalkyl group having 1 to 6 carbon atoms, L 1 represents a saturated hydrocarbon group having 1 to 24 carbon atoms, —CH 2 — in the saturated hydrocarbon group is optionally replaced by —O— or —CO—, and a hydrogen atom in the saturated hydrocarbon group is optionally substituted with a fluorine atom or a hydroxy group, and Y 1 represents a methyl group which optionally has a substituent, or an alicyclic hydrocarbon group having 3 to 24 carbon atoms which optionally has a substituent, and —CH 2 — in the alicyclic hydrocarbon group is optionally replaced by —O—, —S—, —SO 2 — or —CO—.
  9. 9 . The salt according to claim 1 , wherein the hydrocarbon group for R 4 is an alkyl group, an alicyclic saturated hydrocarbon group, an aromatic hydrocarbon group, or a group formed by combining two or more of the alkyl group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group.
  10. 10 . An acid generator comprising the salt according to claim 1 .
  11. 11 . A resist composition comprising the acid generator according to claim 10 and a resin having an acid-labile group.
  12. 12 . The resist composition according to claim 11 , wherein the resin having an acid-labile group includes at least one selected from the group consisting of a structural unit represented by formula (a1-0), a structural unit represented by formula (a1-1) and a structural unit represented by formula (a1-2): wherein, in formula (a1-0), formula (a1-1) and formula (a1-2), L a01 , L a1 and L a2 each independently represent —O— or *—O—(CH 2 ) k1 —CO—O—, k1 represents an integer of 1 to 7, and * represents a bonding site to —CO—, R a01 , R a4 and R a5 each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which optionally has a halogen atom, R a02 , R a03 and R a04 each independently represent an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group obtained by combining these groups, R a6 and R a7 each independently represent an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these groups, m1 represents an integer of 0 to 14, n1 represents an integer of 0 to 10, and n1′ represents an integer of 0 to 3.
  13. 13 . The resist composition according to claim 11 , wherein the resin having an acid-labile group includes a structural unit represented by formula (a2-A): wherein, in formula (a2-A), R a50 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which optionally has a halogen atom, R a51 represents a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group or a methacryloyloxy group, A a50 represents a single bond or *—X a51 -(A a52 -X a52 ) nb —, and * represents a bonding site to carbon atoms to which —R a50 is bonded, A a52 represents an alkanediyl group having 1 to 6 carbon atoms, X a51 and X a52 each independently represent —O—, —CO—O— or —O—CO—, nb represents 0 or 1, and mb represents an integer of 0 to 4, and when mb is an integer of 2 or more, a plurality of R a51 are the same or different from each other.
  14. 14 . The resist composition according to claim 11 , further comprising a salt generating an acid having an acidity lower than that of an acid generated from the acid generator.
  15. 15 . A method for producing a resist pattern, which comprises: (1) a step of applying the resist composition according to claim 11 on a substrate, (2) a step of drying the applied resist composition to form a composition layer, (3) a step of exposing the composition layer, (4) a step of heating the exposed composition layer, and (5) a step of developing the heated composition layer.

Description

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a salt, an acid generator, a resist composition and a method for producing a resist pattern. Description of the Related Art JP 2020-015713 A mentions a salt represented by the following formula and a resist composition comprising the salt as an acid generator. JP 2020-015716 A mentions a salt represented by the following formula and a resist composition comprising the salt as an acid generator. JP 2020-046661 A mentions salts represented by the following formulas and resist compositions comprising the salts as acid generators, respectively. JP 2018-118962 A mentions a salt represented by the following formula and a resist composition comprising the salt as an acid generator. SUMMARY OF THE INVENTION The present invention provides a salt capable of forming a resist pattern with CD Uniformity (CDU) which is better than that of a resist pattern formed from the resist compositions comprising the salts mentioned above. The present invention includes the following inventions. [1] A salt represented by formula (I): wherein, in formula (I), R4, R5, R6, R7, R8 and R9 each independently represent a halogen atom, a haloalkyl group having 1 to 12 carbon atoms or a hydrocarbon group having 1 to 18 carbon atoms, the hydrocarbon group may have a substituent, and —CH2— included in the haloalkyl group and the hydrocarbon group may be replaced by —O—, —S—, —CO— or —SO2—,A1, A2 and A3 each independently represent a hydrocarbon group having 2 to 20 carbon atoms, the hydrocarbon group may have a substituent, and one of —CH2— included in the hydrocarbon group may be replaced by —O—, —CO—, —S— or —SO2—,m1 represents an integer of 0 to 5, and when m1 is 2 or more, a plurality of groups in parentheses may be the same or different from each other,m2 represents an integer of 0 to 4, and when m2 is 2 or more, a plurality of groups in parentheses may be the same or different from each other,m3 represents an integer of 0 to 4, and when m3 is 2 or more, a plurality of groups in parentheses may be the same or different from each other,m4 represents an integer of 0 to 5, and when m4 is 2 or more, a plurality of R4 may be the same or different from each other,m5 represents an integer of 0 to 5, and when m5 is 2 or more, a plurality of R3 may be the same or different from each other,m6 represents an integer of 0 to 5, and when m6 is 2 or more, a plurality of R6 may be the same or different from each other,m7 represents an integer of 0 to 5, and when m7 is 2 or more, a plurality of R7 may be the same or different from each other,m8 represents an integer of 0 to 4, and when m8 is 2 or more, a plurality of R8 may be the same or different from each other,m9 represents an integer of 0 to 4, and when m9 is 2 or more, a plurality of R9 may be the same or different from each other,in which 0≤m1+m7≤5, 0≤m2+m8≤4, 0≤m3+m9≤4, and at least one of m1, m2 and m3 represents an integer of 1 or more,X4 represents a single bond, —CH2—, —O—, —S—, —CO—, —SO— or —SO2—, andAI− represents an organic anion. [2] The salt according to [1], wherein A1 is *—X01-L01- or *-L01-X01—, A2 is *—X02-L02- or *-L02-X02—, and A3 is *—X03-L03- or *-L03-X03— (X01, X02 and X03 each independently represent —O—, —CO—, —S— or —SO2—, L01, L02 and L03 each independently represent a hydrocarbon group having 1 to 19 carbon atoms, the hydrocarbon group may have a substituent, and * represents a bonding site to the benzene ring to which R4, R3 or R6 may be bonded).[3] The salt according to [2], wherein X01, X02 and X03 are each independently —O— or —S—.[4] The salt according to [2] or [3], wherein L01, L02 and L03 are each independently an alkanediyl group having 1 to 6 carbon atoms.[5] The salt according to any one of [1] to [4], wherein when m4, m5 or m6 is an integer of 1 or more, R4, R3 and R6 are each independently a fluorine atom, an iodine atom, a perfluoroalkyl group having 1 to 4 carbon atoms or an alkyl group having 1 to 4 carbon atoms (—CH2— included in the alkyl group may be replaced by —O— or —CO—).[6] The salt according to any one of [1] to [5], wherein when m7, m8 or m9 is an integer of 1 or more, R7, R8 and R9 are each independently a fluorine atom, an iodine atom, a perfluoroalkyl group having 1 to 4 carbon atoms or an alkyl group having 1 to 4 carbon atoms (—CH2— included in the alkyl group may be replaced by —O— or —CO—).[7] The salt according to any one of [1] to [6], wherein AI− is a sulfonic acid anion, a sulfonylimide anion, a sulfonylmethide anion or a carboxylic acid anion.[8] The salt according to any one of [1] to [7], wherein AI− is a sulfonic acid anion, and the sulfonic acid anion is an anion represented by formula (I-A): wherein, in formula (I-A), Q1 and Q2 each independently represent a hydrogen atom, a fluorine atom, an alkyl group having 1 to 6 carbon atoms or a perfluoroalkyl group having 1 to 6 carbon atoms,L1 represents a saturated hydrocarbon group