Optical properties of In$_{2}$Se$_{3}$ thin films

In$_{2}$Se$_{3}$ films are produced by ion-beam evaporation at substrate temperatures of 313 and 623 K. As the target, In$_{2}$Se$_{3}$ single crystals grown by the vertical Bridgman method are used. The composition and structure of the crystals and films are determined by the X-ray spectral analysis and X-ray diffraction techniques, respectively. It is established that the crystals and films crystallize with the formation of a hexagonal structure. The band gap and refractive index of the In$_{2}$Se$_{3}$ films are determined from the transmittance and reflectance spectra. It is found that, as the substrate temperature is increased, the band gap increases.