The surface quality of -phase films which had been grown onto Si(100) by means of chemical vapor deposition was assessed by making synchrotron photo-emission measurements of the valence band and of the line-widths and surface-induced structures in Si 2p core-level spectra. In these n-type samples, the band bending was small on the c(2 x 2) and (3 x 2) surfaces but larger on the (2 x 1) surface, which also exhibited an increased Si 2p line-width and evidence of elemental Si patches. All 3 reconstructions exhibited emission from gap states that extended from the valence-band maximum to the Fermi level.

V.M.Bermudez, J.P.Long: Applied Physics Letters, 1995, 66[4], 475-7