Organometallic vapor-phase epitaxial growth of Al xGa 1− xSb and Al xGa 1− xAs ySb 1− y

Abstract

This paper reports, for the first time, atmospheric pressure organometallic vapor phase epitaxial growth of Al x Ga 1− x Sb and Al x Ga 1− x As y Sb 1− y thin films. The layers were grown on InAs and GaSb substrates at a temperature of 560°C usin trimethylaluminum, trimethylgallium, trimethylantimony, and arsine as source materials. For Al x Ga 1− x Sb, layers with x up to 0.85 were obtained and photoluminescence was observed for x < 0.2. The band gap is indirect for x ≥ 0.22. Al x Ga 1− x As y S 1− y layers covering nearly the entire range of Al and As compositions, even those within the miscibility gap region, were obtained. Excellent surfaces were avhieved for Al x Ga 1− x As y Sb 1− 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.