Comparison of thermal stabilities between Ge-Sb-Te and In-Sb-Te phase change materials

Crystallization temperatures, activation energies, and thermal diffusivities of In3Sb1Te2 (IST) and Ge2Sb2Te5 (GST) are investigated with a differential scanning calorimetry, a xenon laser flash, and a transmission electron microscopy. The activation energies for crystallizing the IST and the GST are 5.2 eV and 3.31 eV, respectively. The thermal diffusivity of the IST is about a half of the GST. The thermal diffusion length in the IST-phase change random access memory cell is relatively shorter than the GST due to lower thermal diffusivity. Experimental results reveal that the IST is more thermally stable than the GST. (C) 2013 AIP Publishing LLC.