Temperature dependent thermal conductivity and transition mechanism in amorphous and crystalline Sb₂Te₃ thin films

Sb₂Te₃ thin films are widely used in high density optical and electronic storage, high-resolution greyscale image recording, and laser thermal lithography. Thermal conductivity and its temperature dependence are critical factors that affect the application performance of thin films. This work aims to evaluate the temperature dependence of thermal conductivity of crystalline and amorphous Sb₂Te₃ thin films experimentally and theoretically, and explores into the corresponding mechanism of heat transport. For crystalline Sb₂Te₃ thin films, the thermal conductivity was found to be 0.35 ± 0.035 W m^-1 K^-1 and showed weak temperature dependence. The thermal conductivity of amorphous Sb₂Te₃ thin films at temperatures below ~450 K is about 0.23 ± 0.023 W m^-1K^-1, mainly arising from the lattice as the electronic contribution is negligible; at temperatures above 450 K, the thermal conductivity experiences an abrupt increase owing to the structural change from amorphous to crystalline state. The work can provide an important guide and reference to the real applications of Sb₂Te₃ thin films.