Direct observation of adsorbate induced band gap states on GaAs(110).
01 January 1986
Normally unoccupied adsorbate induced states within the GaAs band gap were studied by measuring ultraviolet photoemission spectra from pulsed laser-excited surfaces. Strikingly similar discrete structures within the gap were observed for sub-monolayer coverages of both chemisorbed oxygen and gold. The implications of these results for the understanding of Fermi-level pinning at interfaces are discussed.