Detection of oxygen incorporated in molecular-beam epitaxy grown GaAs-on-AlAs interfaces and AlAs layers by secondary ion mass spectrometry

Abstract

By employing a long growth interruption (GI) in molecular beam epitaxy, we have successfully determined the concentration of oxygen incorporated in GaAs/AlAs interfaces and AlAs layers by secondary ion mass spectrometry. The concentration of oxygen atoms incorporated on AlAs surfaces during GI is found to be proportional to the period of GI when the incoming fluxes of residual oxygen-related species reach steady-state values. The net incorporation rate of oxygen on the AlAs surface is found to be constant for a wide range of substrate temperatures from 540 to 620 °C, indicating that the oxygen desorption is negligible.