S. Petillon

Wurtzite ZnxCd1 − xS layers grown by combining MBE and hot-wall beam epitaxy

Abstract Zn x Cd 1 − x S alloy layers revealing the wurtzite modification have been successfully grown by molecular beam epitaxy for the first time. The hexagonal crystal structure is achieved by using a wurtzite CdS buffer layer deposited by hot-wall beam epitaxy on a GaAs(111)B substrate. Characterization of the alloy films includes in situ RHEED investigations, X-ray diffraction and optical measurements. TEM diffraction patterns and reflection spectra are used to confirm the Zn x Cd 1 − x S alloys to be of the wurtzite type. Photoluminescence is dominated by localized exciton emission. For layers with high Zn content ( x > 0.4), film quality decreases due to the increased mismatch to the CdS buffer and the fact, that the stable bulk phase for Zn-rich alloys is cubic.