Calorimetric measurements of structural relaxation and glass transition temperatures in sputtered films of amorphous Te alloys used for phase change recording

摘要

Sputtered amorphous Ge_4Sb_1Te_5, Ge_1Sb_2Te_4, Ge_2Sb_2Te_5, and Ag_(0.055)In_(0.065)Sb_(0.59)Te_(0.29) thin films were studied by differential scanning calorimetry. Upon continuous heating, heat release due to structural relaxation of the amorphous phase between 0.5 and 1.0 kJ/mol was observed. This value depends on the thermal history of the sample. Preannealing of the amorphous phase revealed the glass transition temperature T_g within 10 K of the crystallization temperature upon continuous heating at 40 K/min.