Substrate temperature dependence of vapor phase deposition of all-inorganic lead-free CsSnBr₃ perovskite thin films

Abstract

We report the effect of substrate temperature on the vapor phase deposition of all-inorganic lead-free tin halide perovskite CsSnBr3 thin films by co-evaporation of CsBr and SnBr2. The amount of SnBr2 supplied had little effect on the thin film when the substrate temperature exceeded the SnBr2 cell temperature (180°C) indicating that the three-temperature growth was realized. The polycrystalline CsSnBr3 thin films obtained by three-temperature growth showed micrometer-scale grains and no by-products. The average grain size increased for higher substrate temperatures following the Arrhenius law with an activation energy of 6.6 kJ/mol.