CRYSTAL GROWTH, PHASE TRANSFORMATIONS, AND ELECTRICAL PROPERTIES OF METASTABLE GALLIUM ANTIMONIDE-GERMANIUM ALLOYS

Single crystal metastable (GaSb)(,1-x)Ge(,x) alloys have been grown on GaAs substrates with compositions across the GaSb-Ge pseudobinary phase diagram. The alloys transformed to the equilibrium state through a continuous series of metastable states at a rate limited by diffusion. Ion bombardment during growth had a strong influence on the transformation rate kinetics; however, no preferential sputtering occurred during the sputter growth of as-deposited single phase alloys. The measured enthalpies of transformation from the crystalline metastable to the equilibrium state agreed with enthalpies predicted using the regular solution model. The measured carrier concentrations and mobilities were consistent with the materials being disordered.