Studies on the physical properties of CdS thin films with different S/Cd molar ratios fabricated by spray pyrolysis technique using perfume atomizer

Cadmium sulfide thin films with different S/Cd molar ratios have been deposited on glass substrates by employing spray pyrolysis technique using perfume atomizer at 325°C. Cadmium chloride and thiourea salts were used as sources for cadmium and sulfur ions respectively. The effect of S/Cd molar ratio on the structural, morphological, electrical and optical properties of the films was investigated. X-ray diffraction studies reveal that irrespective of S/Cd molar ratio, all the films exhibit hexagonal phase with a (0 0 2) preferential orientation. Crystallite size increases as the S/Cd molar ratio increases up to 1 and then decreases for higher S/Cd molar ratio. Film coated with S/Cd molar ratio equal to 1 has low values of strain (1.662 x 10-3) and dislocation density (1.214 x 1014 lines/m2) which confirms the improved crystallinity of this film. Optical studies show that all the films are highly transparent. All the films have resistivity in the order of 10-1 ohm-cm.