Patent ID: 8841061
Filing Date: 2014-09-23
Classification: C08F,G03F,Y10S

Abstract:
1. A positive resist composition comprising as a base resin a polymer (a) comprising carboxyl groups whose hydrogen is substituted by an acid labile group having general formula (2): wherein R 1 is methylene or ethylene, R 2 is a straight, branched or cyclic C 1 -C 8 alkyl, C 6 -C 10 aryl, or C 2 -C 10 alkenyl group, which may contain an oxygen or sulfur atom, R 3 is trifluoromethyl, and m is an integer of 1 to 4, X 1 is a single bond, —C(═O)—O—R 5 —, phenylene or naphthylene group, R 5 is a straight, branched or cyclic C 1 -C 10 alkylene group which may have an ester radical, ether radical or lactone ring, and R 4 is hydrogen or methyl, and the polymer (a) has a weight average molecular weight of 1,000 to 500,000.