Properties Of Epitaxial Cdte On Si(lll) With a (Ca,Ba)F2 Buffer Layer

Abstract

ABSTRACTEpitaxial CdTe has been grown onto Si(lll) wafers by MBE with the aid of a composition graded (Ca,Ba)F2 buffer layer to surmount the large misfit of 19%. Untwinned CdTe layers with smooth surfaces, narrow X-ray lines and strong photoluminescence with a narrow near band edge peak were obtained. The results indicate a comparable structural quality to well known CdTe layers on sapphire, InSb or GaAs used as buffers to grow (Hg, Cd)Te for IR-device applications. In addition, the CdTe layers are near strain free despite a large thermal expansion mismatch. This is most probably due to dislocations which are able to move along the fluoride/Si interface even after growth and down to near room temperature.