Optical and Electrical properties of ZnS thin films prepared by spraypyrolysis

Zinc Sulfide semiconductor ceramics, a II-VI group semiconductor materials possessing a highdirect band gap about ۳.۶۶ (eV) in the near-UV region, are currently being intensively studied bymaterial scientists, physicists and chemists due to their multifaceted applications especially inopto-electronic devices. In this report, thin films of ZnS were deposited on the well-cleaned glassand silicon substrates at various substrate temperatures through a simple and low cost spraypyrolysis technique. X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM),Ultraviolet-Visible (UV-Vis) spectroscopy were used to investigate the effect of substratetemperature on some structural features and optical properties of the ZnS thin films. It was foundthat at the lowest substrate temperatures (۳۰۰ ◦C) the ZnS films are almost amorphous form. Withincreasing substrate temperature, the crystalline quality was improved. The surface morphologyof the ZnS films prepared at high temperatures is relatively more homogeneous and dense withno cracks also optical characterization revealed that as-prepared thin films show opticaltransmittance more than ۹۵% in visible range. In the following, we have examined the optoelectricalproperties of ZnS thin films as a function of substrate temperature and realized that thehigh substrate temperature and good crystallinity strongly affect subsequent opto-electronicproperties