ORGANOMETALLIC VAPOR-PHASE EPITAXIAL-GROWTH OF ALXGA1-XSB AND ALXGA1-XASYSB1-Y

This paper reports, for the first time, atmospheric pressure organometallic vapor phase epitaxial growth of AlxGa1-xSb and AlxGa1-xAsySb1-y thin films. The layers were grown on InAs and GaSb substrates at a temperature of 560-degrees-C using trimethylaluminum, trimethylgallium, trimethylantimony, and arsine as source materials. For AlxGa1-xSb, layers with x up to 0.85 were obtained and photoluminescence was observed for x < 0.2. The band gap is indirect for x greater-than-or-equal-to 0.22. AlxGa1-xAsySb1-y layers covering nearly the entire range of Al and As compositions, even those within the miscibility gap region, were obtained. Excellent surfaces were achieved for AlxGa1-xAsySb1-y layers lattice matched to InAs substrates. A large As distribution coefficient was observed, as thermodynamically predicted. It was found that Al incorporation was increased as the As concentration in the solid increased.