Temperature dependent optical properties of SnO₂ film study by ellipsometry

Abstract

In this study, columbite phase tin oxide film was deposited onto quartz glass using the thermal evaporation method. An ellipsometry experiment was performed at the temperature of 25 °C-600 °C. B-spline with K-K consistence was used to describe the optical constants of SnO2 film to obtain the temperature dependent film thickness and optical constants. Results of X-ray diffraction pattern (XRD) confirmed an irreversible phase transition from columbite to the rutile structure at the temperature range of 100 to 300 °C, which had remarkably reduced the film thickness and resulted in the blue shift of the absorption edge. Besides, the total and partial densities of states (TDOS and PDOS) for both rutile and columbite phase SnO2 were also calculated based on the first-principles in accordance with the density functional theory, so as to clarify the structure properties of these two phases.