Optical properties of CdS thin films deposited by close space sublimation

Highly transparent cadmium sulphide thin films were fabricated at relatively low temperatures by employing the close space sublimation technique. The maximum optical transmittance in the visible region for CdS layer with the ~0.48 μm thickness reached 80%. The optical band gap varies slowly with thickness in the range of 2.42 -2.44 eV. The lowest direct absorption edge produces a reflection peak at 2.42 or 2.43 eV at room temperature depending on the thicknesses. We report curves for refractive, extinction coefficients and optical conductivity for CdS with different thicknesses.