Temperature Dependence of Electrical Properties and Thickness of II-VI Solid-Solution of CdTe Thin Films Prepared by Spray Pyrolysis

CdTe thin films deposited by using aqueous solution of cadmium chloride and tellurium tetrachloride of 0.02 M of each at differentsubstrate temperature from 3000C to 3750C in the interval of 250C. Arrhenius plot show the each curve has two segments. At lower temperature region 300 K to 450 K shallow trapping state appears due to the formation of interstitial of cadmium or telluride vacancies are expected to dominate the extrinsic conductivity near room temperature while at higher temperature region 450 K to 573 K deep traps appears to be operative. As the preparation temperature of the films increases, the activation energy also increases. This indicates the increases of grain size of the films which reduces the grain boundary effect. Indicating the formation of polycrystalline films of n-type semiconductor.