Salt and photoresist composition comprising the same

Patent metadata

Field	Value
Publication number	US-9612533-B2
Application number	US-201514601895-A
Country	US
Kind code	B2
Filing date	Jan 21, 2015
Priority date	Jan 24, 2014
Publication date	Apr 4, 2017
Grant date	Apr 4, 2017

Abstract

A salt which generates an acid by light irradiation, said salt comprising:
an acid-labile group having an acetal structure from which group a moiety having a fluorine-containing base-labile group is removed by bring into contact with the acid.

First claim

What is claimed is:

1. A salt which generates an acid by light irradiation, said salt comprising:
an acid-labile group having an acetal structure from which group a moiety having a fluorine-containing base-labile group is removed by bringing into contact with the acid, and
having a group represented by formula (a):

wherein X a and X b each independently represent an oxygen atom or a sulfur group;
* represents a binding site; and
X 1 represents a divalent group represented by formula (X 1 -1), formula (X 1 -2), formula (X 1 -3) or formula (X 1 -4):

where R 1 , R 2 , R 3 , R 4 , R 5 and R 6 each independently represents a C1-C6 fluoroalkyl group and * represents a binding site to X a or X b .

2. The salt according to claim 1
which consists of a cation and an anion having the acid-labile group.

3. The salt according to claim 2
wherein the cation is an arylsulfonium cation.

4. The salt according to claim 1
which has a moiety represented by formula (a1):

Wherein X a , X b and X 1 are as defined in claim 1 ;
a ring W represents a C3-C36 alicyclic hydrocarbon group in which a methylene group can be replaced by an oxygen atom, a sulfur atom, a carbonyl group or a sulfonyl group, and in which a hydrogen atom can be replaced by a hydroxy group, a C1-C12 alkyl group, a C1-C12 alkoxy group, a C3-C12 alicyclic hydrocarbon group, a C6-C10 aromatic hydrocarbon group or a combination of any two or more of them; and * represents a binding site.

5. The salt according to claim 4
wherein the ring W is a C6-C 10 alicyclic hydrocarbon group in which a methylene group can be replaced by an oxygen atom, a sulfur atom, a carbonyl group or a sulfonyl group, and in which a hydrogen atom can be replaced by a hydroxy group, a C1-C12 alkyl group, a C1-C12 alkoxy group, a C3-C12 alicyclic hydrocarbon group, a C6-C10 aromatic hydrocarbon group or a combination of any two or more of them.

6. The salt according to claim 4
wherein the moiety represented by formula (a1) forms an anion represented by formula (a2):

in which X a , X b , X 1 and the ring W are as defined in claim 4 ;
L b1 represents a C1-C24 divalent saturated hydrocarbon group where a methylene group can be replaced by an oxygen atom or a carbonyl group and where a hydrogen atom can be replaced by a fluorine atom or a hydroxy group; and
Q 1 and Q 2 each independently represent a fluorine atom or a C1-C6 perfluoroalkyl group.

7. The salt according to claim 6
wherein L b1 is *—CO—O—(CH 2 ) t — where t is an integer of 0 to 6 and * represents a binding site to C(Q 1 )(Q 2 ), or *—CH 2 —O—CO— where * represents a binding site to C(Q 1 ) (Q 2 ).

8. An acid generator which comprises the salt according to claim 1 .

9. A photoresist composition comprising
the acid generator according to claim 8 and
a resin which has an acid-labile group.

10. The photoresist composition according to claim 9 , further comprising a salt which generates an acid having an acidity weaker than an acid generated from the acid generator.

11. A process for producing a photoresist pattern comprising the following steps (1) to (5):
(1) a step of applying the photoresist composition according claim 9 on a substrate,
(2) a step of forming a composition film by conducting drying,
(3) a step of exposing the composition film to radiation,
(4) a step of baking the exposed composition film, and
(5) a step of developing the baked composition film.

Assignees

• Sumitomo Chemical Co

Inventors

• Masuyama Tatsuro
• Ichikawa Koji
• Yamamoto Satoshi

Classifications

• G03F7/0045 Primary

  with organic non-macromolecular light-sensitive compounds not otherwise provided for, e.g. dissolution inhibitors · CPC title

• G03F7/0046

  with perfluoro compounds, e.g. for dry lithography (G03F7/0048 takes precedence) · CPC title

• C07C43/12

  containing halogen · CPC title

• G03F7/0397

  the macromolecular compound having an alicyclic moiety in a side chain · CPC title

• C07D317/72 Primary

  spiro-condensed with carbocyclic rings · CPC title