Onium salts and positive resist materials using the same

摘要

Disclosed are novel onium salts represented by general formula (R)3S<+>M, wherein three R's may be the same or different, each being an aryl group, provided that at least one of R's is a t-alkoxy substituted phenyl group, and M is an anion capable of forming the sulfonium salts; and high energy radiation-responsive positive resist materials using said novel onium salts as acid generator.