The effect of ultrathin selenium overcoat on the stability of tellurium-based optical recording media
Abstract
An ultrathin selenium overcoat about 20-40 Å thick was found to be quite effective in retarding both the uniform and the localized degradation rate of tellurium-based optical recording media in room ambient and high humidity and temperature accelerated testing environments. Results from X-ray photoelectron spectroscopy analyses of selenium-overcoated tellurium films and TeSe alloy films suggested the formation of a high selenium concentration TeSe alloy for the selenium-overcoated film. The effect of the selenium overcoat is interpreted in terms of the presence of this TeSe alloy which is capable of retarding both the oxidation and weight loss degradation mechanisms reported previously for thin tellurium films. This interpretation is consistent with the results from the electrochemical studies made on these films in that the open-circuit potential of the selenium-overcoated films corresponds to those for TeSe alloy films having about 90% Se. © 1987.