Thin te and te alloy films for optical data storage

Abstract

Laser writing sensitivity, contrast ratio, and archival stability are used to evaluate Te and various Te-alloy thin film media for optical data storage application. The alloys studied include Te-Se, Te-Ge, and Te-Bi. Optical properties pertinent to laser writing sensitivity and contrast ratio such as light absorption and reflectivity are reported for these films. No significant degradation in the light absorption and reflectivity are observed if the concentration of these alloying elements is less than e.g., 10wt%. The stability of these films is studied by monitoring the change in light transmission, measured both over a large area and locally using a scanning laser beam. The presence of this small amount of alloying elements is found to significantly improve the chemical stability of Te films. Examples concerning the physical stability of amorphous optical recording media are presented and discussed. © 1983 SPIE.