Radiation-sensitive resin composition, resist pattern-forming method, acid generator and compound
The present invention provides a radiation-sensitive resin composition that contains a polymer having a structural unit that includes an acid-labile group; and an acid generator, wherein the acid generator includes a compound including a sulfonate anion having SO 3 − , wherein a hydrogen atom or an electron-donating group bonds to an α carbon atom with respect to SO 3 − , and an electron-withdrawing group bonds to a β carbon atom with respect to SO 3 − ; and a radiation-degradable onium cation. The compound preferably has a group represented by the following formula (1-1) or (1-2). In the following formulae (1-1) and (1-2), R 1 and R 2 each independently represent a hydrogen atom or a monovalent electron-donating group. R 3 represent a monovalent electron-withdrawing group. R 4 represents a hydrogen atom or a monovalent hydrocarbon group.
1. A radiation-sensitive resin composition, comprising:
a polymer comprising a structural unit which comprises an acid-labile group; and
at least one acid generator comprising a first acid generator represented by formula (2), and optionally a second acid generator other than the first acid generator:
wherein in the formula (2):
Z represents a group represented by formula (1-1) or (1-2);
X represents OCO—;
n is an integer of 1;
R 5 represents a cycloalkyl group, or a group comprising a lactone structure;
wherein in the formulae (1-1) and (1-2):
R 1 and R 2 each independently represent a hydrogen atom or a methyl group;
R 3 represents a cyano group;
R 4 represents a hydrogen atom; and
M + represents a monovalent radiation-degradable onium cation.
2. The radiation-sensitive resin composition according to claim 1 , wherein the radiation-degradable onium cation is a sulfonium cation or an iodonium cation.
3. The radiation-sensitive resin composition according to claim 1 , wherein the structural unit that includes an acid-labile group is represented by formula (4):
wherein in the formula (4),
R 7 represents a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group;
R 8 represents a monovalent hydrocarbon group having 1 to 20 carbon atoms;
R 9 and R 10 each independently represent a monovalent linear hydrocarbon group having 1 to 10 carbon atoms or a monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms; and
R 9 and R 10 optionally taken together represent an alicyclic structure having 3 to 20 carbon atoms together with the carbon atom to which R 9 and R 10 bond.
4. A resist pattern-forming method, comprising:
applying the radiation-sensitive resin composition according to claim 1 on a substrate to form the resist film;
exposing the resist film; and
developing the exposed resist film.
5. The radiation-sensitive resin composition according to claim 1 , wherein a content of the first acid generator in the at least one acid generator is in a range of 25% by mass to 90% by mass.
6. The radiation-sensitive resin composition according to claim 1 , wherein a content of the first acid generator in the at least one acid generator is in a range of 30% by mass to 70% by mass.
7. The radiation-sensitive resin composition according to claim 1 , further comprising an acid diffusion controller.
8. The radiation-sensitive resin composition according to claim 1 , further comprising a fluorine atom-containing polymer other than the polymer.
9. The radiation-sensitive resin composition according to claim 1 , wherein Z represents a group represented by formula (1-1).
10. The radiation-sensitive resin composition according to claim 9 , wherein R 1 and R 2 each represent a hydrogen atom.
11. A compound represented by formula (2):
wherein in the formula (2):
Z represents a group represented by formula (1-1) or (1-2);
X represents OCO—;
n is an integer of 1;
R 5 represents a cycloalkyl group, or a group comprising a lactone structure;
wherein in the formulae (1-1) and (1-2):
R 1 and R 2 each independently represent a hydrogen atom or a methyl group;
R 3 represents a cyano group;
R 4 represents a hydrogen atom; and
M + represents a monovalent radiation-degradable onium cation.
12. The compound according to claim 11 , wherein Z represents a group represented by formula (1-1).
13. The compound according to claim 12 , wherein R 1 and R 2 each represent a hydrogen atom.