Salt, acid generator, resist composition and method for producing resist pattern

Patent metadata

Field	Value
Publication number	US-11840503-B2
Application number	US-202117246868-A
Country	US
Kind code	B2
Filing date	May 3, 2021
Priority date	May 15, 2020
Publication date	Dec 12, 2023
Grant date	Dec 12, 2023

Abstract

A salt represented by formula (I), a generator and a resist composition:

wherein R 1 and R 2 each independently represent an iodine atom, a fluorine atom or an alkyl fluoride group having 1 to 6 carbon atoms; R 4 , R 5 , R 7 and R 8 each independently represent a halogen atom, a hydroxy group, a haloalkyl group having 1 to 12 carbon atoms or an alkyl group having 1 to 12 carbon atoms, —CH 2 — included in the haloalkyl group and the alkyl group may be replaced by —O—, —CO—, —S— or —SO 2 —; X 1 and X 2 each independently represent an oxygen atom or a sulfur atom; m1 represents 1 to 5, m2 and m8 represent 0 to 5, and m4, m5 and m7 represent an integer of 0 to 4, in which 1≤m1+m7≤5, 0≤m2+m8≤5; and AI − represents an organic anion.

First claim

The invention claimed is:

1. A salt represented by formula (I):

wherein, in formula (I),
R 1 and R 2 each independently represent an iodine atom,
R 7 and R 8 each independently represent a halogen atom, a hydroxy group, a haloalkyl group having 1 to 12 carbon atoms or an alkyl group having 1 to 12 carbon atoms, and —CH 2 —included in the haloalkyl group and the alkyl group may be replaced by —O—, —CO—, —S— or —SO 2 —,
X 1 and X 2 represent an oxygen atom,
m1 represents an integer of 1 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 5, and when m2 is 2 or more, a plurality of groups in parentheses may be the same or different from each other,
m4 represents an integer of 2, a plurality of R 4 may be the same or different from each other,
m5 represents an integer of 2, a plurality of R 5 may be the same or different from each other,
m7 represents an integer of 0 to 4, and when m7 is 2 or more, a plurality of R 7 may be the same or different from each other,
m8 represents an integer of 0 to 5, and when m8 is 2 or more, a plurality of R 8 may be the same or different from each other,
in which 1≤m1+m7≤5, 0≤m2+m8≤5,
one of R 4 s represents an iodine atom and the other represents a hydroxy group,
one of R 5 s represents an iodine atom and the other represents a hydroxy group, and AI − represents an organic anion.

2. The salt according to claim 1 , wherein m1 is 1 or 2, and m2 is 0, 1 or 2.

3. The salt according to claim 1 , wherein the binding site of X 1 and X 2 are bound to the p-position or the m-position with respect to the binding site of I + .

4. The salt according to claim 1 , wherein m2 is 0, m8 is 1, and R 8 is a branched alkyl group having 3 or 4 carbon atoms.

5. The salt according to claim 1 , wherein both m1 and m2 are 1.

6. The salt according to claim 1 , wherein both m1 and m2 are 2.

7. The salt according to claim 1 , wherein AP is a sulfonic acid anion, a sulfonylimide anion, a sulfonylmethide anion or a carboxylic acid anion.

8. The salt according to claim 1 , wherein AP 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 fluorine atom 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 —included in the saturated hydrocarbon group may be replaced by —O— or —CO—, and a hydrogen atom included in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, and
Y 1 represents a methyl group which may have a substituent or an alicyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and —CH 2 — included in the alicyclic hydrocarbon group may be replaced by —O—, —SO2— or —CO—.

9. An acid generator comprising the salt according to claim 1 .

10. A resist composition comprising the acid generator according to claim 9 and a resin having an acid-labile group.

11. The resist composition according to claim 10 , wherein the resin having an acid-labile group includes at least one of a structural unit represented by formula (a1-1) and a structural unit represented by formula (a1-2):

wherein, in formula (a1-1) and formula (a1-2),
L a1 and L a2 each independently represent —O— or *—O—(CH 2 ) k1 —O—, k1 represents an integer of 1 to 7, and * represents a bond to —CO—,
R a4 and R a5 each independently represent a hydrogen atom or a methyl group,
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 obtained 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.

12. The resist composition according to claim 10 , further comprising a salt generating an acid having an acidity lower than that of an acid generated from the acid generator.

13. A method for producing a resist pattern, which comprises:
(1) a step of applying the resist composition according to claim 10 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.

14. The salt according to claim 1 , wherein AI + is at least one selected from anions represented by formula (I-A-25), formula (I-A-26), formula (I-A-27), formula (I-A-30), formula (I-A-31) and formula (I-A-36):

wherein in formula (I-A-25), formula (I-A-26), formula (I-A-27), formula (I-A-30), formula (I-A-31) and formula (I-A-36);
R i5 and R i6 each independently represent an alkyl group having 1 to 4 carbon atoms,
L A41 is a single bond or an alkanediyl group having 1 to 4 carbon atoms, and
Q b1 and Q b2 each independently represent a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms.

15. A salt represented by formula (I):

wherein, in formula (I),
R 1 and R 2 represent an iodine atom,
R 4 , R 5 and R 7 each independently represent an iodine atom, a hydroxy group, or an alkyl group having 1 to 12 carbon atoms
R 8 represents an alkyl group having 1 to 4 carbon atoms,
X 1 and X 2 represent an oxygen atom,
m1 represents an integer of 1 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 5, and when m2 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 4, and when m4 is 2 or more, a plurality of R 4 may be the same or different from each other,
m5 represents an integer of 0 to 4, and when m5 is 2 or more, a plurality of R 5 may be the same or different from each other,
m7 represents an integer of 0 to 4, and when m7 is 2 or more, a plurality of R 7 may be the same or different from each other,
m8 represents an integer of 1 to 5, and when m8 is 2 or more, a plurality of R 8 may be the same or different from each other,
in which 1≤m1+m7≤5, 0≤m2+m8≤5, and
AI + represents an organic anion.

16. The salt according to claim 15 , wherein m2 represents an integer of 0.

17. The salt according to claim 15 , wherein AI + is at least one selected from anions represented by formula (I-A-25), formula (I-A-26), formula (I-A-27), formula (I-A-30), formula (I-A-31) and formula (I-A-36):

wherein in formula (I-A-25), formula (I-A-26), formula (I-A-27), formula (I-A-30), formula (I-A-31) and formula (I-A-36):
R i5 and R i6 each independently represent an alkyl group having 1 to 4 carbon at

Assignees

• Sumitomo Chemical Co

Inventors

• Komuro Katsuhiro
• Ichikawa Koji

Classifications

• C07C309/17 Primary

  containing carboxyl groups bound to the carbon skeleton · CPC title

• C07C303/32

  of salts of sulfonic acids · CPC title

• C07C309/06

  containing halogen atoms, or nitro or nitroso groups bound to the carbon skeleton · CPC title

• C07C309/12

  containing esterified hydroxy groups bound to the carbon skeleton · CPC title

• C07D321/06 Primary

  1,3-Dioxepines; Hydrogenated 1,3-dioxepines · CPC title