DLTS Study of Electron Traps in n-GaAs Grown by Gas Source Molecular Beam Epitaxy Using Triethylgallium and AsH3

Abstract
Deep level transient spectroscopy has been carried out in n-GaAs grown by gas source molecular beam epitaxy (GSMBE) using triethylgallium (TEG) and AsH3. Seven electron traps have been observed, five of which correspond to those reported in n-GaAs grown by conventional MBE. The concentration of E L2 was below the detection limit of about 1×1012 cm-3. The concentrations of the dominant traps, which correspond to M1, M2' and M4, decreased as the AsH3/TEG flow-rate ratio increased. High-quality GaAs layers with a total trap concentration as low as about 2×1013 cm-3 have been grown even at a low growth temperature of 550°C.