Antireflection coatings on metal layers for photolithographic purposes

Abstract

The image formation in photoprojection and contact printing systems is frustrated by the existence of standing waves in the photosensitive resist layer, and the reflections will cause blurring of the image. This problem is most severe for coherent illuminated systems and for realization of patterns in highly conducting substrates such as metals. A number of materials which can be used as spacers to reduce the reflected wave in the resist are theoretically investigated and experimentally tested. The use of a spacer reduces exposure time and increases the edge sharpness of the resist’s intensity profile.