Element III Segregation During Mocvd Growth on Structured Substrates

Abstract

AbstractThe crystal habits of GaAs and GaAlAs grown on structured substrates by Metalorganic Chemical Vapor Deposition (MOCVD) have been investigated. The growth behavior was delineated by depositing alternating thin layers of AlGaAs and GaAs over grooves and mesas. A strong temperature dependence of facet growth rate and an anisotropy of Al composition with facet orientation are observed. This latter effect so far undocumented in MOCVD has been analysed by Auger Electron Spectroscopy performed on cleaved cross-sections. BCF theory has been used to extract quantitative microscopic data. These observations demonstrate the importance of surface effects and provide an insight into MOCVD growth mechanisms.