Characterization of CdTe film grown on a Si(111) substrate

Abstract

We report the characterization of polycrystalline CdTe films grown on Si(111) by using UHV sublimination techniques. Films grown at substrate temperature below 250 degrees C exhibited streaked X-ray diffraction patterns. To understand the native oxide on the film surface, the films were exposed to a laboratory air environment in the growth chamber for several days. The XPS spectra were taken after each Ar-ion sputtering of these oxidized films. In order to obtain more information from the measured XPS data, we performed core-level line-shape analysis. Based on previously reported studies, CdTe, TeO2, and element Te are constituents in the film, while Cd is almost all in the CdTe state. Raman scattering from oxidized CdTe film in the frequency of 550-900 cm(-1) reveals that TeO2 is the predominant oxide.