[en] Effect of In and Ge doping in the form of In₂Ge₈Sb₈₅Te₅ on optical and thermal properties of eutectic Sb₇₀Te₃₀ alloys was investigated. Crystalline structure of In₂Ge₈Sb₈₅Te₅ phase change material consists of a mixture of phases. Thermal analysis shows higher crystallization temperature and activation energy for crystallization. Isothermal reflectivity-time measurement shows a growth-dominated crystallization mechanism. Ultrafast crystallization speed of 30 ns is realized upon irradiation by blue laser beam. The use of ultrafast and thermally stable In₂Ge₈Sb₈₅Te₅ phase change material as mask layer in aperture-type super-resolution near-field phase change disk is realized to increase the carrier-to-noise ratio and thermal stability