Modification of the optical constants in amorphous Sb2Se3:Sn thin films under the illumination and heat treatment

The optical properties of chalcogenide glasses present a great scientific interest for the establishment of the general legitimacy of interaction of the optical irradiation with the amorphous solids, as well as a practical interest. The effect of light-induced photostructural transformations in amorphous chalcogenides films have been initiated many applications of amorphous material in photonics and optoelectronics, especially as inorganic photo-resists for sub-micron technology. The optical parameters of amorphous Sb2Se3 and Sb2Se3:Sn. (x=0.01, 0.5, 10 at. Sn %) prepared by vacuum evaporation on glass substrates was determined from transmission spectra. The band gap was found to be E-g=1.30 eV for amorphous Sb2Se3 and decrease with increasing of tin concentration up to E-g=1.0 eV for Sb2Se3:Sn-10.0. for determination of the refractive index the approximation method proposed by Valeev was used. The maximum modifications of the refractive index under the light irradiation Delta n (Delta n=0.20) occur for the composition Sb2Se3:Sn-0.01. That allows us to conclude that doping of amorphous Sb2Se3 films with small concentrations of tin initiate the photostructural transformations under the light irradiation, and make these materials suitable for registration of optical and holographic information.