Organometallic vapor phase epitaxial growth of AlSb-based alloys

High-quality AlGaSb and lattice-matched AlGaAsSb alloys were grown on GaSb substrates by organometallic vapor phase epitaxy (OMVPE) using tritertiarybutylaluminum, triethylgallium, trimethylantimony, and tertiarybutylarsine. The surface morphology of all layers is excellent, and photoluminescence is observed for layers with direct-gap compositions. Nominally undoped layers exhibit p-type conductivity, which is attributed to carbon as measured by secondary ion mass spectroscopy. n-Type doping of AlGaSb and AlGaAsSb was achieved over the whole Al composition range by using diethyltellurium. Lattice-matched GaSb/AlGaAsSb double-heterostructure diode lasers that emit at 1.75 mu m operate under pulsed conditions at room temperature.