A study of the crystallization kinetics of Ge20Te80 chalcogenide glass

A hulk Ge20Te80 glass was prepared using a melt-quench technique. The crystallization mechanism was studied using differential scanning calorimetry (DSC), scanning electron microscopy and x-ray diffraction. DSC was performed at different heating rates under non-isothermal conditions. From the heating-rate dependence of the temperature of the glass transition, T-g, and the peak temperature of crystallization, T-p, the average value of the activation energy for the glass transition, E-g, and the average value of the activation energy for crystallization, E-c, were calculated for the Ge20Te80 glass. The crystallization mechanism was examined in terms of recent analyses developed for use under non-isothermal conditions. The results indicate that the glassy Ge20Te80 has three-dimensional growth, the average value of the order of the crystallization mechanism, n, is 3.5 +/- 0.1. The average values of E-g and E-c are 223.3 +/- 5.1 and 134.9 +/- 3.6 kJ mol(-1), respectively.