Control of crystal orientation of CdTe epitaxial layers grown on (0Â 0Â 1) GaAs with ZnSe buffer layer by molecular beam epitaxy

CdTe layers were grown on (0 0 1) GaAs substrates with a ZnSe buffer layer by molecular beam epitaxy. The high-quality ZnSe (0 0 1) epitaxy on GaAs allows us to control the II-VI/III-V heterovalent interface prior to the CdTe deposition. By subsequently adjusting the interface between ZnSe and CdTe, it was possible to selectively obtain the growth of either (0 0 1) or (1 1 1) CdTe epitaxial layers on the (0 0 1) ZnSe/GaAs substrate. Reflection high energy electron diffraction indicates that the nucleation of the CdTe epitaxial layers turns two-dimensional within a few seconds of initiating the growth. X-ray diffraction and photoluminescence measurements indicate that both the (1 1 1) and the (0 0 1) CdTe films are of high structural quality despite the large lattice constant mismatch of 14.6% between CdTe and the (0 0 1) ZnSe/GaAs substrate.