Effect of thermodiffusion on perfection of crystal structures formed by condensation from vapor phase

Abstract

Results are reported of an investigation of the effect of nonuniform synthesis conditions stimulating thermodiffusion on the perfection of the crystalline structure of cadmium telluride films synthesized in vacuum by condensation from the vapor phase. Results of technological, geometrical, electorgraphical, and electron-microscopic studies are given. It is shown that the positive effect of the nonuniform conditions on the perfection of the crystalline structure formed has a thresholdlike character. In the case where thermodiffusion takes place, the substrate temperature has an unusual effect on the crystalline perfection of the film obtained. Against expectations, raising the substrate temperature tends to increase the disorder in the structure. It has been found that thermodiffusion affects the duration of the Ostwald ripening phase and therefore provides a means of controlling the structure formation processes. The experimental data are shown to agree with the theory of the film formation processes.