Spectral and X-Ray Studies of Indium Oxide Films on Sapphire Substrates

Abstract

The results of studying the optical transmission and X-ray diffraction spectra of thin In2O3 films obtained by DC magnetron sputtering on Al2O3 (012) substrates are presented. The diffraction patterns contain a reflex corresponding to the (222) plane of cubic In2O3. Its position shifts from 30.3° to 30.6° with decreasing film thickness. The half-width of this reflex decreases with decreasing deposition time, which may indicate an increase in the grain size of the film material. According to measurements of optical transmission, at the interface between the film and the substrate, the presence of a transition layer with a band gap of 1.39 eV and a thickness of about 40 nm was established. The properties of this layer are independent of the deposition time.