WURTZITE ZNXCD1-XS LAYERS GROWN BY COMBINING MBE AND HOT-WALL BEAM EPITAXY

ZnxCd1-xS alloy layers revealing the wurtzite modification have been s uccessfully grown by molecular beam epitaxy for the first time. The he xagonal crystal structure is achieved by using a wurtzite CdS buffer l ayer deposited by hot-wall beam epitaxy on a GaAs((1) over bar (1) ove r bar (1) over bar)B substrate. Characterization of the alloy films in cludes in situ RHEED investigations, X-ray diffraction and optical mea surements, TEM diffraction patterns and reflection spectra are used to confirm the ZnxCd1-xS alloys to be of the wurtzite type. Photolumines cence is dominated by localized exciton emission. For layers with high Zn content (x > 0.4), film quality decreases due to the increased mis match to the CdS buffer and the fact, that the stable bulk phase for Z n-rich alloys is cubic.