Structural, Morphological and Optical Properties of (Cu2S)100-x(SnS2)x Thin Films

Abstract

The structural , optical and morphological properties of SnS2 , Cu2S thin films and their mixture prepared by spray pyrolysis technique , were studied. SnS2 , Cu2S thin films and their mixture were deposited on glass substrates at temperature of 334°C, 283°C and 300°C respectively. XRD studies showed that all the prepared films were polycrystalline in nature with a hexagonal structure and the preferential orientation for Cu2S thin film was along (002) plane , while the preferential orientation for SnS2 thin films was along (101) plane . The absorbance and transmittance spectra have been recorded in the wavelength (310-1100) nm in order to study the optical properties . It was found that the electronic transitions on fundamental absorption edge were direct allowed and the values of the optical energy gap for SnS2 andCu2S was equal to 2.2eV and 2.35eV respectively. Also it was found that the values of the optical energy gap for the mixture decreased with the increase in SnS2 in the mixture from (2.32-2.22) eV. The optical constants which include refractive index and extinction coefficient as a function of photon energy were also studied.