Patent ID: 7727701

Claim:
A positive resist composition, comprising a resin component (A), which contains acid dissociable, dissolution inhibiting groups and displays increased alkali solubility under action of acid, and an acid generator component (B) that generates acid on exposure, wherein said resin component (A) comprises a structural unit (a1) represented by a general formula (I) shown below: (wherein, R represents a hydrogen atom or methyl group, and m represents an integer from 1 to 3), a structural unit (a2) in which a hydroxyl group of said general formula (I) has been protected by substituting a hydrogen atom thereof with an acid dissociable, dissolution inhibiting group (II) represented by a general formula (II) shown below: (wherein, R 1 represents an alkyl group of 1 to 5 carbon atoms, R 2 represents an alkyl group of 1 to 5 carbon atoms or a hydrogen atom, and X represents an unsubstituted adamantyl group), and a structural unit (a3) in which a hydroxyl group of said general formula (I) has been protected by substituting a hydrogen atom thereof with an acyclic acid dissociable, dissolution inhibiting group (III), wherein said acid dissociable, dissolution inhibiting group (III) is a chain-like tertiary alkoxycarbonyl group, and wherein said resin component (A) comprises a polymer (A1), which contains said structural unit (a1) and said structural unit (a2) but does not contain said structural unit (a3), and a polymer (A2), which contains said structural unit (a1) and said structural unit (a3) but does not contain said structural unit (a2).