The image formation by photo – reaction of Ag or Al with glassy chalcogenides: mechanisms and application

Abstract

The mechanisms and application of photo-dissolution (PD) of silver in chalcogenide glassy semiconductors (ChGS) , as well as of electrically controlled photoreaction (ECPR) of aluminum with ChGS are extensive reviewed and discussed. It is shown that one of the main interesting application of these phenomena is due to possibility of their use for image formation, followed by appearance of differential chemical etching rate between exposed and unexposed portions of either ChGS - Ag or Al - ChG – metal wafers. This property is utilized to form the surface relief, which results in a wide application of Ag (Al) – ChGS structures in the microelectronic lithography as high-resolution inorganic photoresists. The advantages of these photoresists are: the possibility to obtain layers with high homogeneity and low concentration of defects on a large area, the possibility of wet and dry processing, the high absorption coefficient of light, which enhance the accuracy of simultaneous or successive etching.