Thickness- and Deposition Rate-Dependence of Structural Characteristics of Evaporated CdTe Films

The dependence of the structural characteristics of evaporated CdTe films on the deposition parameters was investigated by X-ray diffraction. All deposited films were single phase of cubic zincblende structure and showed strong preferential orientation with <111> fiber texture. The Voigt method of single reflection was used for line profile analysis to determine the crystallite size and microstrain. The internal microstrain decreases sharply at smaller thickness and became thickness-independent for values larger than 500 nm, where as the degree of preferred orientation and the crystallite size increase monotonously. The increase of deposition rate was found to improve the stoichiometry, to increase the degree of preferred orientation and to decrease the crystallite size as well as the internal microstrain. The structural characteristic variations were discussed in relation to the effect of the deposition parameters during film preparation.