Metastable GaAsBi Alloy Grown by Molecular Beam Epitaxy

GaAs1-xBix has been grown at a substrate temperature (Tsub) between 350 and 410 C by MBE. The relationship between GaBi molar fraction (x) evaluated by RBS and the lattice constant showed good linearity. To achieve Bi incorporation into the epilayer, As flux was adjusted in a limited range on the brink of As shortage on the growing surface. The Bi incorporation was saturated at a large Bi flux, probably due to a low miscibility of Bi with GaAs. The value of x increased up to 4.5% with decreasing Tsub to 350 C. 10 refs.