SCHOTTKY-BARRIER AND SURFACE PHOTOVOLTAGE INDUCED BY SYNCHROTRON-RADIATION IN GAP(110)/AG

We measure the Schottky-barrier formation and the surface photovoltage induced by synchrotron radiation by complementing photoemission measurements with a Kelvin probe. This combined technique is applied to the Ag/GaP(110) interface, grown at room temperature. Large photovoltage shifts are observed up to high coverage. Based on decomposition of the Ga 3d core-level line shapes and surface photovoltage corrections, we conclude that the evolution of the Fermi level takes place during the deposition of about 15 angstrom, yielding a final Schottky barrier of 1.15 eV.