Direct Etching of Resists by UV Light

Abstract

Etching characteristics of some positive working resists by means of ultraviolet light irradiation were evaluated. Degradable resist polymers were found to be etched effectively in a room atmosphere and at a comparatively low temperature. The pure PMIPK [poly (methyl isopropenyl ketone)] showed that the greatest etching rate and fine resist patterns could be obtained directly by the UV-etching method. It is pointed out that the UV-etching method can be applied, as the simplest dry method, to making resist patterns as well as to ashing the resists.