Abstract

Raster scanning with a laser image generator operating in a polar coordinate system is applied for recording of an arbitrary-topology diffraction structure [1]. The synthesis technology of element masks is based on the effects of thermo-chemical modifications in thin metal films (chromium, 100-200 nm thick). Nanosecond-pulse radiation causes the growth of an oxide layer, its etching rate being many times lower than the etching rate of chromium. It allows one to carry out negative recording of a mask structure [2]. The pattern transfer into glass and formation of a binary, multilevel and continuous profile is performed by means of photolithography methods [3].

© 1992 Optical Society of America