Onium salts and the use therof as latent acids

Abstract

A chemically amplified photoresist composition comprising, (a) a compound which cures upon the action of an acid or a compound whose solubility is increased upon the action of an acid; and (b) as photosensitive acid donor, at least one compound of the formula Ia, Ib, Ic, IIb or IIc wherein Ris for example C-Calkyl, C-Ccycloalkyl, C-Chaloalkyl, C-Calkenyl, C-Ccycloalkenyl, C-Cbicycloalkenyl, phenyl, naphthyl, anthracyl, phenanthryl, or is a heteroaryl radical; all of which are unsubstituted or substituted; optionally some of the substituents form 5- or 6-membered rings with further substituents on the phenyl, naphthyl, anthracyl, phenanthryl, or heteroaryl ring or with one of the carbon atoms of the phenyl, naphtyl, anthracyl, phenanthryl, or heteroaryl ring; R'is for example C-Calkylene, C-Ccycloalkylene, phenylene, naphtylene, diphenylene, or oxydiphenylene, wherein these radicals are unsubstituted or substituted; A and B for example are a direct bond; Arand Arindependently of each other for example are phenyl, naphtyl, anthracyl, phenanthryl, or heteroaryl, all of which are unsubstituted or are substituted; Ar, Arand Arfor example have one of the meanings given for Arand Ar; Y is for example C-C-Ccycloalkylene, phenylene, naphthylene, diphenylene, or oxydiphenylene, all of which are unsubstituted or substituted.