Nucleation and Growth of Epitaxial Cadmium Selenide Electrodeposited on InP and GaAs Single Crystals

Epitaxial CdSe layers were electrodeposited from aqueous solutions onto InP and GaAs single crystals. The analysis of current transients shows that the growth kinetics corresponds to the Scharifker model assuming a progressive nucleation followed by three-dimensional diffusion-limited growth. Diffusion control is effective after less than 0.1 s after the beginning of the potential pulse. The phenomena associated with the formation of a coherent film cannot be detected by this technique. Transmission electron microscopy observations of CdSe films with increasing thicknesses show when the diffusion control is effective, a large density of growth steps followed by the formation of epitaxial nuclei which finally coalesce.