LEAD SELENIDE THIN FILMS FROM VACUUM EVAPORATION METHOD-STRUCTURAL AND OPTICAL PROPERTIES

Thin films of PbSe of different thickness have been prepared on glass substrates in room temperature by vacuum deposition. The thickness of the deposited films is measured by employing quartz crystal monitor method. PbSe thin film of thickness 500 angstrom has amorphous structure. When the increase in thickness is from 1000 angstrom to 2000 angstrom, the films have polycrystalline structure which are identified by X-ray diffraction, scanning electron microscopic and atomic force microscopic studies. The structural parameters such as interplanar distance (d), lattice parameter (a), grain size (D), dislocation density (rho) and microstrain (epsilon) have been evaluated. The optical properties have been studied in the range of wavelength 2500-5000nm. The optical band gap values of different thicknesses have been estimated and reported in this paper.