Stoichiometry Related Phenomena in Low Temperature Grown GaAs

Abstract

AbstractThe growth of GaAs at low temperatures (LT-GaAs) at or below 250 °C, under standard Molecular Beam Epitaxy (MBE) growth conditions, usually results in a massive incorporation of excess As in the lattice which then totally dominates the electrical and optical characteristics of the as grown material. We report on new phenomena associated with the growth of GaAs at 250 °C and we show, for the first time, data on highly electrically active doped material. By careful control of the growth conditions, namely As4/Ga flux ratios, material in which total defect concentrations of less than 1017 cm-3, well below the huge 1020 cm-3 that is normally obtained in LT-GaAs, can be achieved thereby demonstrating that high quality GaAs can in effect be grown at extremely low temperatures.