Effect of Cadmium Sources on Structural and Optical Properties of Nanocrystalline CdS Thin Films Prepared by CBD Technique

Nanocrystalline Cadmium sulfide (CdS) thin films have been prepared by chemical bath deposition technique on commercial glass substrates at 70 oC using cadmium chloride, cadmium sulfate and cadmium acetate as a cadmium source. While thiourea (CS(NH2)2) used as a source of sulfur and ammonia solution (NH4OH) were added to maintain the pH value of the solution at 10. Crystalline structure and optical properties of the as-deposited thin films were analyzed by x-ray diffraction and UV-VIS spectrophotometer technique, respectively. X-ray diffraction study indicates that the grown Cadmium sulfide films have cubic structure. The optical characterizations show that the values of band are 3.59, 3.7 and 3.77 eV depending on cadmium source. The films show high transmittance above 65% in the VIS – NIR range of the solar spectrum. Keyword: Nanocrystalline thin films, Cadmium sulfide, chemical bath deposition.