STUDIES OF CDTE SURFACES WITH SECONDARY ION MASS-SPECTROMETRY, RUTHERFORD BACKSCATTERING AND ELLIPSOMETRY

The composition and the stability of chemically etched, mechanically polished and oxidized surfaces of single crystals of cadmium-telluride were studied by secondary ion mass spectroscopy (SIMS), Rutherford backscattering (RBS) and ellipsometry. CdTe surfaces etched using a solution of bromine in methanol were found to be enriched in cadmium but a film, identified to be an oxide of tellurium, was observed to grow on it at room temperature and in air. The thickness of this film increased over long periods of time t linearly versus ln t. Mechanically polished samples and also chemically etched surfaces which were oxidized in a solution of hydrogen peroxide in amoniac were found to be stable. © 1979 Springer-Verlag.