Nanocrystalline Cadmium Sulphide (CdS) thin films have been deposited onto the microscopic glass substrates by sol-gel spin coating method using cadmium nitrate and thiourea as precursor solutions. The influence of sol aging time and annealing temperature on the structural, surface morphological and optical properties were studied by X-Ray Diffraction method (XRD), Field Emission Scanning Electron Microscopy (FESEM) with Energy Dispersive X-ray Analysis (EDAX), Photoluminescence (PL) study and UV-Visible spectroscopy. The XRD study reveals that CdS films have crystalline hexagonal structure with dominant (0 0 2) orientation and that the crystallite size increases with increase in annealing temperature. The aging time of the starting solutions was also found to have an evident effect on the crystallite sizes. FESEM studies reveal that the grains are spherically shaped and distributed uniformly over the entire surface of the substrate. The elemental compositions of the films were observed by EDAX spectrum. The UV-Visible spectral analysis showed that the calculated direct band gap values were found to decrease with increase in annealing temperature. These results suggest that the appropriate aging of CdS sol is an important parameter for the improvement of structural quality of CdS thin films derived by sol – gel method and it could be a good potential candidate for optoelectronic devices.
Rathinamala, I.; J.Pandiarajan; N.Jeyakumaran; and N.Prithivikumaran
"Synthesis and Physical Properties of nanocrystalline CdS Thin Films – Influence of sol Aging Time & Annealing Temperature,"
International Journal of Thin Film Science and Technology: Vol. 3
, Article 6.
Available at: https://digitalcommons.aaru.edu.jo/ijtfst/vol3/iss3/6