An investigation was made of the de-capped (311)A surface by using scanning tunnelling microscopy and synchrotron radiation photo-emission techniques. It was found that, although the data were in general agreement with the proposed structural model for (311)A, there were considerable differences in the surface order. In particular, the As dimer rows were unbroken over much shorter length scales and were highly kinked. There was a correspondingly lower degree of anisotropy in the surface roughness than had previously been reported. No (8 x 1) reconstruction was observed. An analysis of the As 3d and Ga 3d core-level photo-emission spectra suggested that surface As atoms were present in only one bonding configuration, while surface Ga atoms had 2 different bonding states.

P.Moriarty, Y.R.Ma, A.W.Dunn, P.H.Beton, M.Henini, C.McGinley, E.McLoughlin, A.A.Cafolla, G.Hughes, S.Downes, D.Teehan, B.Murphy: Physical Review B, 1997, 55[23], 15397-400