The T-P phase diagrams of amorphous GaSb, InSb and InAs

Abstract

A thermodynamic two-level model is developed and applied for description of metastable phase equilibria in amorphous GaSb, InSb and InAs alloys. The metastable T-P phase diagrams are calculated for these alloys, which include the lines of the semiconductor-to-metal transitions as well as the boundaries of complete thermodynamic instability of the semiconducting or metallic phases. The calculated phase transitions are of first-order, and the transition lines terminate at critical points which are in the region of negative pressures. It is shown that a tendency to spontaneous amorphization of a metastable crystalline high-pressure phase produced by quenching under pressure, the amorphization parameters and a semiconductor-to-metal transition in the amorphous state are conditioned by the interrelation between the positions of the lines in the actual equilibrium (stable) and calculated metastable phase diagrams.