Optical Properties of Polycrystalline Zinc Selenide Thin Films

Umesh Khairnar, Sulakshana Behere, Panjabrao Pawar

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DOI: 10.4236/msa.2012.31006                

Abstract

Thin films of ZnSe have been deposited onto glass substrates at 373 K by thermal evaporation technique. The X-ray diffractogram confirmed that ZnSe has cubic type crystal structure. The lattice parameters of thin films are almost matching with the JCPDS 5 - 552 data for Zinc Selenide. The transmittance and reflectance have been measured at normal and near normal incidence, respectively, in the spectral range 200 - 2500 nm. The dependence of absorption coefficient, α in the photon energy have been determined. Analysis of the result showed that films of different thicknesses, direct transition occurs with band gap energies ranges from 2.2 to 2.6 eV. Refractive indices and extinction coefficients have been evaluated in the above spectral range.

Keywords

Optical Materials; Vapour Deposition; X-Ray Diffraction; Band Gap

Conflicts of Interest

The authors declare no conflicts of interest.

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