Determination of the interdiffusion coefficient for the CdS/CdTe heteroestructure by AES sputter depth profiling

Double heterostructures were prepared by depositing CdTe films on stainless steel (ss) substrates by the close spaced sublimation (CSS) method. The CdTe films were treated with a saturated solution of CdCl2 in methanol, dried in air and annealed at 400 °C. CdS layer of 0.2 μm was deposited on the CdTe film by the chemical bath method. The CdS/CdTe system was treated with saturated solution of CdCl2 in methanol and annealed for 30 min in air at different temperatures from 300 to 400 °C. The samples were characterized by scanning electron microscopy (SEM) and Auger electron spectroscopy (AES). The main effect of the temperature is to change the surface morphology of the CdS film from polycrystalline to an amorphous texture. By AES depth profiling the diffusion processes of the constituent element of the film was studied.