Patent ID: 8062829

Claim:
A chemically amplified resist composition, comprising: a resin which includes a structural unit having an acid-labile group in a side chain, a structural unit represented by the formula (I): wherein X 1 represents a hydrogen atom, a C 1 to C 4 alkyl group, or a C 1 to C 4 perfluoroalkyl group, Y in each occurrence independently represent a hydrogen atom or an alkyl group, and n is an integer of 1 to 14, R 1 , R 2 , R 3 and R 4 independently represent a hydrogen atom, an alkyl group, or a haloalkyl group, and a structural unit having a polycyclic lactone structure, and which is soluble in an organic solvent and insoluble or poorly soluble in an alkali aqueous solution but rendered soluble in an alkali aqueous solution by the action of an acid; and an acid generator represented by the formula (II): A + E − (II) wherein A + represents an organic counterion, E − represents CF 3 SO 3 − , C 2 F 5 SO 3 − , C 4 F 9 SO 3 , N(SO 2 C 2 F 5 ) 2 − , N(SO 2 C 4 F 9 ) 2 − , N(SO 2 C 6 H 5 ) 2 − , C(SO 2 CF 3 ) 3 − , R 21 O(CO)C(Y 1 )(Y 2 )SO 3 − wherein R 21 represents an optionally substituted C 1 to C 30 hydrocarbon group, in which at least one methylene group may be optionally substituted with a carbonyl group or an oxygen atom, and Y 1 and Y 2 independently represent a fluorine atom or a C 1 to C 6 perfluoroalkyl group; and wherein the structural unit having the polycyclic lactone structure is at least one structual unit selected from the group consisting of a structual units represented by the formulae (IVa), (IVb) and (IVc), wherein R 30 in each occurrence represent a C 1 to C 4 alkyl, a carboxyl group or a cyano group, R 31 represents a C l to C 4 alkyl group, t represents an integer of 0 to 3, Z 3 represents a single bond or a —[CH 2 ] k —COO— group, and k represents an integer of 1 to 4.