Effect of bi additive on optical and electrical properties of quaternary chalcogenide InSUB3/SUBTeSUB7/SUBBixSeSUB90-x /SUBthin films

摘要

Glassy alloy of In3Te7BixSe90-x (x = 0,5,10,15) are prepared by melt-quenchingtechnique.Thin filmsare deposited by the thermal evaporation technique on glasssubstrates under a pressure of 10-6torr. The structural analyses of these films were carriedout by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and EnergyDispersive X-ray Scattering (EDS).X-ray diffraction (XRD) of thin films was carried outto analyze the amorphous or polycrystalline behavior of the thin films. EDS analysisshows the presence of the compositional elements in the thin films.SEM shows the surfacemorphology of the thin films and development of grains. Optical studies were carried outby the Ultra violet visible (UV-Vis)Sperctoscopy in the range of 190-1100 nm.Theanalysis of optical absorption spectra shows indirect optical band gap. The optical bandgap decreases with increasing Bismuth concentration from 1.38 eV to 1.02 eV. The DCconductivity was carried out in specially designed metallic sample holder with vacuum 10-4Torr.The DC conductivity of thin films of In3Te7BixSe90-x increases and the correspondingactivation energy decreases with increasing of bismuth content which may be due to shiftin Fermi level.