A study was made of GaAs(100) layers, grown by means of low-temperature molecular beam epitaxy, using valence-band and core-level photo-electron spectroscopy. Small differences were found between valence-band spectra from low-temperature layers and from corresponding layers grown at high temperatures. A new component was found, in the 3d spectra of Ga, in low-temperature GaAs. The relative intensity of this component was found to be essentially constant as a function of probe depth. It was proposed that this component represented sites which were coordinated to 5-atom As clusters formed at AsGa antisites. This implied the presence of a higher density of antisite defects, in the near-surface region, than that typically found in the bulk.

Photoemission Study of GaAs(100) Grown at Low Temperatures. H.Åsklund, L.Ilver, J.Kanski, J.Sadowski, M.Karlsteen: Physical Review B, 2002, 65[11], 115335 (6pp)