SYNCHROTRON-RADIATION STUDY OF RB P-GASB(110) INTERFACE FORMATION ANDBAND BENDING AT LOW-TEMPERATURE/

The formation of the Rb/p-GaSb(110) interface at liquid-nitrogen tempe rature is investigated by soft X-ray photoemission spectroscopy using synchrotron radiation. We use the Ga 3d and Sb 4d core levels to monit or the band bending during the interface formation. The deposition of Rb induces an overshoot of 0.3 eV with a final pinning position near t he valence-band maximum. The band bending could be explained by the ex istence of donor levels located at about 0.3 eV above the valence-band maximum. The interface formed at low temperature was found to be much less reactive than observed previously in room-temperature studies.