Effect of bismuth on parameters of a GaInSbAsP solid solution grown on GaSb substrates

Abstract

Heterophase equilibria in the Ga–In–Sb–As–P–Bi system have been analyzed in terms of a simple solution model. We have calculated the stability limits of GaInAsSbPBi solid solutions in the temperature range ~773–873 K and established thermodynamic limitations on their growth. Based on model analysis results, we have grown a GaInAsSbPBi solid solution on a GaSb substrate via temperature-gradient zone recrystallization. It has been shown that the incorporation of bismuth into a GaInAsSbP solid solution extends its stability region, reduces its band gap, and increases the relative lattice mismatch between the layer and substrate at Bi concentrations above 0.3 at %, but reduces the composition region of lattice-matched GaInAsSbPBi/GaSb heterostructures.