カルコゲナイド非晶質半導体め光誘起現象

構造変化と光学変化

抄録

This report reviews recent developments in the investigation of photo-induced optical and structural changes observed in various amorphous chalcogenides. The main subject is the reversible photostructural change in amorphous As₂S₃, and it is shown that the phenomenon is unique to the amorphous state. First, the chemical bonds and electronic structure of the As-S system are determined by the XPS technique. Second, the irreversible photobleaching observed in flash-evaporated As_2+xS₃ is described, and its kinetics are clarified by the detailed structural analyses. Finally, the reversible photostructural change accompanying photodarkening is discussed on the basis of detailed optical and structural studies, leading us towards a more complete understanding of the phenomenon.