Thermal stability improvement and optical band gap behavior in Ge2Te films by Mg-doping

The thermal stability and its crystallization behavior in Ge-Mg-Te films were investigated. The results reveal that the bond combination among Mg, Ge and Te has occurred in Mg-Ge-Te. The formed Mg-Ge and Mg-Te phases increase the crystallization temperature, crystalline resistance and optical band gap. The ratios between amorphous and crystalline states were increased to 108. The crystal phase was changed from Ge2Te to Te. The proper Mg serves as a center for suppression of the Te crystal growth without phase separation for high-stable phase change memory application.