POSITIVE RESIST COMPOSITION AND METHOD OF FORMING RESIST PATTERN

摘要

A positive resist composition which comprises: a resin ingredient (A) whose alkali solubility increases by the action of an acid; and an acid generator ingredient (B) which generates an acid upon exposure to light, wherein the resin ingredient (A) is a mixture of a copolymer (A1) having a structural unit (a1) derived from an acrylic ester containing a cyclic acid-dissociable dissolution-inhibitive group and a copolymer (A1') having a structural unit (a1') derived from an acrylic ester containing a branched acid-dissociable dissolution-inhibitive group. The positive resist composition can form a resist pattern having excellent resolution.