Abstract
Se1-xSx glassy films have been prepared in the thin films form with x in the range 0.0-0.4 and thickness in the range 500-600 nm by thermal vacuum evaporation technique. The amorphous structure of the films was confirmed by XRD measurements. The surface morphology and the thickness of the films were studied by SEM. The optical properties of the films were studied by transmittance method, it was found that the optical constants of the films are sensitive to composition. The refractive index was determined and the data was discussed in the Wemple and DiDomenico model for single effective oscillator. The resultant oscillator energy and strength were then calculated and found to be increased as the composition increases. A blue shift in the absorption edge was observed by increasing the sulfur content and the band gap increases from 1.85 to 2.03 eV as the composition increases from 0.0 to 0.4.