POSITIVE RESIST COMPOSITION AND METHOD FOR FORMING RESIST PATTERN

摘要

Disclosed is a positive resist composition containing a resin component (A) and an acid generator component (B). The resin component (A) is composed of a copolymer having a mono(a-lower alkyl)acrylate unit (a0) containing a carboxy group and/or a hydroxyl group, a mono(a-lower alkyl)acrylate unit (a1) containing an acid-cleavable dissolution inhibiting group, a mono(a-lower alkyl)acrylate unit (b1) containing a lactone ring, and a constitutional unit (c1) derived from the formula (1) below. Also disclosed is a positive resist composition containing a resin component (A)' whose alkali solubility is increased by the action of an acid and the above-described component (B). The resin component (A)' is composed of a star polymer having a core portion containing an acid-cleavable dissolution inhibiting group, and an arm portion containing the constitutional unit (a0). (1) (In the formula, R represents a lower alkyl group or a hydrogen atom; R<SUP>11</SUP> and R<SUP>12</SUP> independently represent a lower alkyl group; n represents an integer of 1-5; and A represents a divalent to hexavalent organic group.)