Nanostructure, optical and electrical properties of CdS_0.1Se_0.9 thin films were studied as a function of film thickness. The results of XRD analysis showed that atfilm thickness,  the films are amorphous structure. While atfilm thickness,  a single phase of CdS_0.1Se_0.9 is formed which has the hexagonal crystal structure with preferential growth along the  direction. The optical constants dependent on the film thickness were investigated. According to Wemple and DiDomenico method, the optical dispersion parameters  and  were determined. CdS_0.1Se_0.9 films of different thickness (131-376nm) displayed the activation energies from 0.2523 to 0.2576eV for lower temperature (LT) region and from 0.3474 to 0.4219eV for higher temperature (HT). The electrical resistivity measurement shows that the films are semiconducting with minimum resistivity of  observed at film thickness of 376nm.

thermal evaporation, X-ray diffraction, electrical resistivity, optical properties.