A photoresist composition, comprising an acid-sensitive polymer comprising a repeating unit having an acid-labile group; an iodonium salt comprising an anion and a cation, the iodonium salt having Formula (1):




wherein Z− is an organic anion; Ar1 is substituted or unsubstituted C4-60 heteroaryl group comprising a furan heterocycle; and R1 is substituted or unsubstituted hydrocarbon group as provided herein, wherein the cation optionally comprises an acid-labile group, wherein Ar1 and R1 are optionally connected to each other via a single bond or one or more divalent linking groups to form a ring, and wherein the iodonium salt is optionally covalently bonded through Ar1 or substituent thereof as a pendant group to a polymer, the iodonium salt is optionally covalently bonded through R1 or substituent thereof as a pendant group to a polymer, or the iodonium salt is optionally covalently bonded through Z− as a pendant group to a polymer; and a solvent.