Abstract

Disclosed is a class of novel cyanooxime sulfonate compounds represented by the general formulaNC--CR1 =N--O--SO2 --R2,in which R1 and R2 are, each independently from the other, an unsubstituted or halogen-substituted monovalent aliphatic hydrocarbon group selected from the group consisting of alkyl, cycloalkyl, alkenyl and cycloalkenyl groups. The group R1 is preferably a cycloalkenyl group, e.g. 1-cyclopentenyl or 1-cyclohexenyl group, and R2 is preferably a lower alkyl group having 1 to 4 carbon atoms. The compound releases an acid by the irradiation with ultraviolet light and is useful as an acid generating agent in an acid-sensitive photoresist composition. By virtue of the high transparency of the compound to ultraviolet, high acid strength of the acid generated therefrom and good solubility of the compound in organic solvents, the photoresist composition compounded with the compound as an acid generating agent is imparted with high sensitivity to ultraviolet and capable of giving a patterned resist layer having excellent characteristics.