Influence of nanostructured SnS thin films for visible light photo detection

SnS thin films were deposited onto glass substrates with different substrate temperature of 50 degrees C, 100 degrees C, 150 degrees C and 200 degrees C by vacuum thermal evaporation at 10(-5) Torr using prepared SnS powder sample as evaporated targets. The structural, electrical and optical properties of substrate temperature influenced SnS films were studied using standard characterization techniques. The X-ray diffraction (XRD) showed that the deposited films are of orthorhombic crystal structure and are polycrystalline in nature. Energy dispersive spectroscopy (EDS) revealed the presence of Sn and S elements in the deposited film and its stoichiometry. Raman studies confirmed the formation of orthorhombic phase SnS films. The optical properties such as film thickness (d), absorption coefficient (alpha), optical band gap (E-g), refractive index (n) and extinction coefficient (k) of the deposited thin films are estimated from the optical transmittance measurements. The optical band gap values were found to be in the range of (1.843-2.075 eV). The visible photoresponsivity and specific detectivity of the films also increased with increasing the substrate temperature.