Chemical interactions at the interface between cadmium telluride and aqueous solutions of HCl-HNO/sub 3/ mixtures

Solutions of the system HCl-HNO/sub 3/-H/sub 2/O are often used for the structural etching and polishing of cadmium telluride, but there is no information in the literature on the rate and mechanism of the reaction of CdTe with these solutions. These investigations show that the solution of cadmium telluride in aqueous solutions of HCl-HNO/sub 3/ mixtures is determined by the concentration of hydrochloric acid retarding the process. In the concentration triangle for HCl-HNO/sub 3/-H/sub 2/O three regions were distinguished, differing with respect to the CdTe solution mechanism. It was shown that in each of these regions the CdTe surface is coated with a film consisting of tellurium and its oxidation products. The thickness of the film also is determined by the hydrochloric acid concentration.