Reactions at the interface of metal/HgCdTe oxide

The interfacial reactions between metals and the anodic oxide of mercury cadmium telluride (MCT) have been studied by polar-angle-dependent x-ray photoelectron spectroscopy. It was found that the deposition of thin metal films (<2 nm) of indium, platinum, and gold reduced the oxidized tellurium of the MCT oxide at the interface. The spectral results show that indium is more reactive than platinum and gold, but the latter two metals still cause similar interfacial interactions. In the study of the reaction mechanism, depositions of indium and gold by direct evaporation ruled out the possibility that the observed interfacial reactions are caused by energetic particles arriving at the surface during sputter deposition. Metal deposition on MCT oxide which was separated from the MCT substrate also ruled out the possibility of metal diffusion through pinholes in the oxide. It is possible that the condensation of metal causes the breaking of tellurium–oxygen bonds and thereby initializes the interfacial reactions.