Phase change optical recording films based on Bi2Te3-Sb2Te3 alloys

Thin films from cross section Bi2Te3-Sb2Te3 were studied in view of glass-c rystal reversible phase change recording by using laser diode irradiation. By adjusting the spherical aberration of the focalization lens and using a Raman microprobe, reflectivity and vibrational profiles of the laser spot w ere performed in order to determine the most sensitive region of the illumi nated area. The optical switch was then analyzed in optimized conditions ov er the whole cross section. When considering identical cycling parameters, the latter appears to be inverted at a critical composition, which depends critically on the layer thickness. (C) 1999 Elsevier Science Ltd.