US Patent 7759045 Chemically amplified positive resist composition

A chemically amplified positive resist composition comprising (A) a salt represented by the formula (I):A+−O3S—R  (I)wherein R represents a 9,10-anthraquinonyl group which may be substituted with at least one group selected from the group consisting of a C1-C4 alkyl group, a C1-C4 alkoxy group and a hydroxyl group, and the C1-C4 alkyl group and the C1-C4 alkoxy group may be substituted, and A+ represents an organic counter cation, and(B) a resin which contains a structural unit which has an acid-labile group and which itself is insoluble or poorly soluble in an aqueous alkali solution but becomes soluble in an aqueous alkali solution by the action of an acid.