COST-EFFECTIVE MASS FABRICATION OF MULTILEVEL DIFFRACTIVE OPTICAL-ELEMENTS BY USE OF A SINGLE OPTICAL-EXPOSURE WITH A GRAY-SCALE MASK ON HIGH-ENERGY BEAM-SENSITIVE GLASS

We present a method for reproducing diffractive optical elements in qu antity. The method is compatible with VLSI microfabrication techniques and involves generating a gray-scale mask. The gray-scale mask is emp loyed in an optical aligner to expose an analog photoresist on any env ironmentally durable substrate, e.g., glass, quartz, semiconductor, or metal, one exposure for each diffractive optical element. After copie s of the mask on the photoresist are developed, many substrates can be processed in parallel in a chemically assisted ion-beam etcher to tra nsfer the microstructures on the analog resists simultaneously onto th e surfaces of the substrates. (C) 1997 Optical Society of America.