Patent ID: 8062825

Claim:
A positive resist composition comprising a resin component (A) comprising an alkali soluble constituent unit (a1) and a constituent unit (a2) having an acid dissociable dissolution inhibiting group in which alkali solubility enhances by an action of an acid, and an acid generator component (B) which generates an acid upon exposure, and tribenzylamine, wherein the resin component (A) comprises a polymer (A11) and a polymer (A21), wherein the polymer (A11) comprises a constituent unit (a11) derived from (α-methyl)hydroxystyrene, a constituent unit (a21) in which hydrogen atoms of a hydroxyl group of the constituent unit (a11) are substituted with an acid dissociable dissolution inhibiting group, no constituent unit derived from an (α-lower alkyl)acrylate ester (a12) having an alcoholic hydroxyl group and no constituent unit (a22) in which hydrogen atoms of an alcoholic hydroxyl group of the constituent unit (a12) are substituted with an acid dissociable dissolution inhibiting group, wherein the constituent unit (a21) has an acid dissociable dissolution inhibiting group (II) represented by the following formula (II) and does not have an acid dissociable dissolution inhibiting group (III) selected from the group consisting of a chain tertiary alkoxycarbonyl group, a chain tertiary alkyl group and a chain tertiary alkoxycarbonylalkyl group, and the polymer (A21) comprises the constituent unit (a11), the constituent unit (a21), no constituent unit (a12) and no constituent unit (a22), wherein the constituent unit (a21) has the acid dissociable dissolution inhibiting group (III) and does not have the acid dissociable dissolution inhibiting group (II): wherein X represents an adamantyl group or a naphthyl group, R 1 represents an alkyl group having 1 to 5 carbon atoms, and R 2 represents an alkyl group having 1 to 5 carbon atoms or a hydrogen atom, wherein the acid generator component (B) is selected from the group consisting of an onium salt-based acid generator, oxime sulfonate-based acid generator, nitrobenzylsulfonate-based acid generator, iminosulfonate-based acid generator and disulfone-based acid generator.