Resist composition, method of forming resist pattern, and compound

1. A resist composition comprising a base component (A) which exhibits changed solubility in a developing solution under action of acid and an acid generator component (B) which generates acid upon exposure,

the acid generator component (B) comprising a sulfonium compound (B1) having a sulfonio group covalently bonded to an anion group represented by general formula (b1-r-1) shown below:

wherein Y 1 represents a divalent linking group or a single bond; L 1 represents an ester bond or a single bond; V 1 represents a divalent hydrocarbon group having a fluorine atom; and n represents 0 or 1, provided that, when L 1 represents a single bond, n=1.

2. The resist composition according to claim 1 , wherein the sulfonium compound (B1) is represented by general formula (b1-1) shown below:

wherein R 1 to R 3 each independently represents an aryl group with or without a substituent, an alkyl group with or without a substituent or an alkenyl group with or without a substituent, provided that zero or two of R 1 to R 3 are mutually bonded to form a ring with the sulfur atom, and at least one of R 1 to R 3 is an aryl group having an anion group represented by general formula (b1-r-1) as a substituent, an alkyl group having an anion group represented by the aforementioned general formula (b1-r-1) as a substituent, or an alkenyl group having an anion group represented by the aforementioned general formula (b1-r-1) as a substituent.

3. The resist composition according to claim 1 , wherein the anion group is represented by general formula (b1-r-1-01) shown below:

wherein Y 1 represents a divalent linking group or a single bond; L 1 represents an ester bond or a single bond; V 11 represents a single bond or an alkylene group of 1 to 10 carbon with or without a fluorine atom; and n represents 0 or 1, provided that, when L 1 is a single bond, n=1; and q is 1 or 2.

4. The resist composition according to claim 1 , wherein the anion group is represented by any one of the following formulae:

5. A method of forming a resist pattern, comprising:

using a resist composition according to claim 1 to form a resist film on a substrate,

subjecting the resist film to exposure,

and subjecting the resist film to developing to form a resist pattern.

6. A sulfonium compound having a sulfonio group covalently bonded to an anion group represented by general formula (b1-r-1) shown below:

wherein Y 1 represents a divalent linking group or a single bond; L 1 represents an ester bond or a single bond; V 1 represents a divalent hydrocarbon group having a fluorine atom; and n represents 0 or 1, provided that, when L 1 represents a single bond, n=1.

7. The sulfonium compound according to claim 6 , which is represented by general formula (b1-1) shown below:

wherein R 1 to R 3 each independently represents an aryl group with or without a substituent, an alkyl group with or without a substituent or an alkenyl group with or without a substituent, provided that zero or two of R 1 to R 3 are mutually bonded to form a ring with the sulfur atom, and at least one of R 1 to R 3 is an aryl group having an anion group represented by general formula (b1-r-1) as a substituent, an alkyl group having an anion group represented by the aforementioned general formula (b1-r-1) as a substituent, or an alkenyl group having an anion group represented by the aforementioned general formula (b1-r-1) as a substituent.

8. The sulfonium compound according to claim 6 , wherein the anion group is represented by general formula (b1-r-1-01) shown below:

wherein Y 1 represents a divalent linking group or a single bond; L 1 represents an ester bond or a single bond; V 11 represents a single bond or an alkylene group of 1 to 10 carbon with or without a fluorine atom; and n represents 0 or 1, provided that, when L 1 is a single bond, n=1; and q is 1 or 2.

9. The sulfonium compound according to claim 6 , wherein the anion group is represented by any one of the following formulae: