Photoelectron spectroscopy study of Ga1−xMnxAs(0 0 1) surface oxide and low temperature cleaning

X-ray photoemission spectroscopy has been used to study Ga0.933Mn0.067As surface cleaning using atomic hydrogen and ex situ HCl etching. Both cleaning techniques are found to reduce the Ga and As surface oxides. Quantitative compositional analysis indicates that a Mn rich surface contamination layer of average thickness 3-4 Å remains in both cases. Beneath the contamination layer the bulk crystal is terminated with a 2 Å thick As layer in the case of etching and a 0.9 Å coverage of Ga for the atomic hydrogen cleaned case.