Iodonium salts as latent acid donors

Abstract

Radiation-sensitive compositions comprising (a1) a cationically or acid-catalytically polymerisable or crosslinkable compound or (a2) a compound that increases its solubility in a developer under the action of acid; and (b) at least one diaryliodonium salt of formula I X is branched C3-C20alkyl or C3-C8cycloalkyl; X1 is hydrogen, linear C1-C20alkyl, branched C3-C20alkyl or C3-C8cycloalkyl; with the proviso that the sum of the carbon atoms in X and X1 is at least 4; Y is linear C1-C10alkyl, branched C3-C10alkyl or C3-C8cycloalkyl; A− is a non-nucleophilic anion, selected from the group (BF4)−, (SbF6)−, (PF6)−, (B(C6F5))4−, C1-C20alkylsulfonate, C2-C20haloalkylsulfonate, unsubstituted C6-C10arylsulfonate, camphorsulfonate, and C6-C10arylsulfonate substituted by halogen, NO2, C1-C12alkyl, C1-C12halo-alkyl, C1-C12alkoxy or by COOR1; and R1 is C1-C20alkyl, phenyl, benzyl; or phenyl mono- or poly-substituted by C1-C12alkyl, C1-C12alkoxy or by halogen; with the proviso that the two phenyl rings on the iodine atom are not identically substituted.

Dependencies are inferred from the claim text.