Proximity correction for e-beam patterned sub-500nm diffractive optical elements

Abstract

In this paper we present two important issues often demanded when patterning DOEs using EBL: the first one is the attainment of accurate resist three-dimensional shaping to increase DOE efficiency, this task is accomplished by developing a new proximity correction algorithm able to shape the resist in one shot of exposure. The second one is the proximity-effect correction of optical gratings having an axial symmetry, whose application is the microfabrication of Fresnel Zone Plates (FZPs); this problem requires the development of a specific algorithm that minimises the computation load by exploiting the grating symmetry.A description of these algorithms is given and examples of proximity compensated DOEs are presented.