Infrared spectroscopic ellipsometry of Ge-doped SbTe alloys

► Fast crystallization of Ge-doped SbTe alloys for phase change memory devices. ► The dielectric function of the thin films in the infrared range is measured. ► Accurate band gap energy values, resistivity, and mean scattering time are obtained. ► The effective mass of holes is estimated. ► In amorphous or crystalline films, optical gap decreased with increasing Sb content.