sohrab Manouchehri - Department of Physics, Faculty of Science, Malek Ashtar University of Technology, Shahinshahr, Isfahan, Iran.
Javad Zahmatkesh - Department of Physics, Faculty of Science, Malek Ashtar University of Technology, Shahinshahr, Isfahan, Iran.
Mohammad Hassan Yousefi - Department of Physics, Faculty of Science, Malek Ashtar University of Technology, Shahinshahr, Isfahan, Iran.

Nanocrystalline PbS thin films are deposited on glass and alumina substratesthrough the chemical bath deposition technique by creating similar conditions, in orderto investigate the effects of the substrate. The structural and optical properties of PbSfilms are investigated by X-ray diffraction, scanning electron microscope, and UV–Vis.The structural analyses of the films indicate that they are of polycrystallineconfigurations and have a face-centered-cubic (fcc) rock-salt structure on differentsubstrates. The X-ray diffraction shows that the structure peaks occur at slightly higherangles in the deposited (grown) films on glass substrate than the ones deposited onalumina substrate. Crystal parameters are exceptionally affected by the type of substrateas well. SEM images reveal that the surface morphology of the PbS thin films is quitedependent upon the nature of the substrate. The optical band gaps of the samples arefound to be ۱.۵۲۱ eV for glass and ۱.۶۷۸ eV for alumina substrates, which are higher incomparison to the bulk value (۰.۴۱ eV). According to the obtained results, PbS thin filmon alumina substrate has narrower particle size distribution, better transmission andlower stress than PbS thin film on glass substrate.

Chemical bath deposition, Optical Properties, Pbs Thin Film, Structural Properties, Substrate