Patent ID: 8029968

Claim:
A positive resist composition, comprising a resin component (A) that exhibits increased alkali solubility under action of acid, and an acid generator component (B) that generates acid upon exposure, wherein (i) said component (A) is a quarternary copolymer that structural units with mutually different structures, and (ii) a proportion of each structural unit within said copolymer 18 to 32 mol %, and the total of the structural units is 100 mol %, (iii) wherein said component (A) comprises structural units (a) derived from (meth)acrylate esters, (iv) wherein said structural units (a) comprise a structural unit (a1) derived from a (meth)acrylate ester that contains an acid-dissociable, dissolution-inhibiting group and structural units (a2) derived from (meth)acrylate esters that contain lactone-containing cyclic groups represented by the following formulas (21) and (24): [wherein in the formula (21), R represents a hydrogen atom or a methyl group, and R 21 and R 22 each represent, independently, a hydrogen atom or a lower alkyl group], and