Effects of post formation thermal annealing of the CdTe–CdS device on the inter-diffusion of S and Te at the junction in a substrate configuration device were studied by Auger electron spectroscopy. While the migration of S and Te atoms increased with annealing temperature, the extent of S diffusion was always higher than the diffusion of Te atoms. Inter-diffusion of S and Te causes the formation of CdTe1-xSx ternary compound at the CdTe–CdS interface.

S and Te Interdiffusion in CdTe/CdS Hetero junction. J.P.Enríquez, E.G.Barojas, R.S.González, U.Pal: Solar Energy Materials and Solar Cells, 2007, 91[15-16], 1392-7