Molecular beam epitaxy of CdSe epilayers and quantum wells on ZnTe substrate

Abstract

We have grown zinc-blende cadmium selenide (CdSe) epilayers on ZnTe-(001) substrate by molecular beam epitaxy (MBE). By controlling the substrate temperature and beam-equivalent pressure (BEP) ratio, of Se to Cd, we determined the most suitable growth condition based on reflection high-energy electron diffraction (RHEED) pattern. At a substrate temperature of 280°C and a BEP ratio of 3.6, the RHEED pattern showed a V-like feature, indicating a rough surface with facets. As the substrate temperature was increased to 360°C at the same BEP ratio, a V-like RHEED pattern moved to a clear streaky pattern. Moreover when the BEP ratio was increased to 4.8 at 360°C of substrate temperature, a clear (2×1) reconstruction of the CdSe layer was observed. A CdSe/CdMgSe single quantum well structure was also grown on ZnTe-(001) substrate by MBE. The RHEED pattern showed a clear (2×1) surface reconstruction during the growth. By photoluminescence measurement, a good optical property of the structure was obtained.