Patent ID: 7273690

Claim:
A positive resist composition for immersion exposure comprising: (A) a resin which enhances a solubility of the resin in an alkaline developer by an action of an acid; and (B) at least one compound which generates an acid upon irradiation with one of an actinic ray and a radiation, the compound (B) being selected from (Bb) and (Bc): (Bb) a sulfonium salt compound having in its cation part a fluorine-substituted alkyl or cycloalkyl residue having 1 or more carbon atoms, and (Bc) a sulfonium salt compound having in its anion part an alkyl or cycloalkyl residue which has 2 or more carbon atoms and has not been substituted by fluorine, wherein the sulfonium salt compound (Bc) comprises an anion represented by general formula (B-2a) or (B2b): wherein Ax represents a single bond or an oxygen atom; Ay represents a single bond, —SO 2 —, —SO 3 —, —SO 2 N(R 4 )—, —CO 2 —, an oxygen atom, —C(═O)—, —C(═O)N(R 4 )—, or an alkylene group; R 4 represents a hydrogen atom or an alkyl group; Az represents a single bond or an aryl group; Yc represents an alkyl or cycloalkyl residue which has 2 or more carbon atoms and has not been substituted by fluorine, provided that Yc may be bonded to R 4 to form a ring; n4 represents an integer of 1-4; n5 represents an integer of 1-4; n6 represents an integer of 0-4; and n7 represents an integer of 0-4, provided that n6+n7 represents an integer of 1-4.