SIMULTANEOUS EXPOSURE OF FILTER GRATINGS AND WAVE-GUIDES BY DIRECT WRITE ELECTRON-BEAM LITHOGRAPHY

A novel process enabling the simultaneous electron-beam exposure of di fferent types of structures is presented, illustrated by the synchrono us generation of filter gratings and waveguides. Optimized results for a precise adjustment of the interface waveguide-grating are shown, as well as the necessity for proximity correction achieved by dose assig nment. The accomodation of the different address grids makes the pre-f ixing of the vertical and horizontal adjustments possible. The structu res are then transferred into the semiconductor by means of dry etchin g. The devices and their characteristic filter curves are presented.