INTERFERENCE PHOTOLITHOGRAPHY USING PHOTOETCHING EFFECT IN CHALCOGENIDE FILMS

The surface roughness of thin amorphous films of chalcogenide glasses (ChG) after photostimulated dissolution in amine-based selective etchant has been investigated. It is established that the rms roughness of the annealed and photoetched ChG film substantially smaller than the as-evaporated film and etched in the same selective etchant. This makes it possible to obtain more higher-quality lithographic masks or periodic relief-phase structures using new photoetching effect: photo-induced enhancement in solubility of annealed ChG layers. A possible mechanism for the photoinduced etching of ChGs is discussed. The diffraction gratings on germanium ChG more environmentally acceptable compounds than traditionally used arsenic chalcogenides, were recorded for the first time by using the effect of photoinduced etching on ChG layers and their characteristics were studied.