METHODS OF FORMING ELECTRONIC MICROCIRCUITS

摘要

A resist is formed on the areas of an electronic microcircuit substrate which are not covered by a pattern of metallic conductors by coating (12) the substrate surface with a positive acting photoresist which is responsive to actinic radiation in a wavelength band which is reflected substantially more by the metallic conductors than the remainder of the substrate surface, blanket exposing (14) the photoresist with said radiation, thus causing greater exposure of the areas of photoresist overlying the metallic conductors than the areas of photoresist overlying the remainder of the substrate surface, and developing (16) the blanket exposed photoresist to remove the areas of photoresist overlying the remainder of the substrate surface.
By alternatively using a negative acting photoresist, a resist can be formed over the pattern of conductors but not over the remainder of the substrate surface.