Reassessment of core-level photoemission spectra of reconstructed SiC(0001) surfaces

In this letter, rye present core-level photoemission spectra recorded from the (root3 x root3)R30 degrees and the (3 x 3) reconstructions of the SiC(0 0 0 1) surface. The results are in agreement with published structure dete rminations by dynamical low energy electron diffraction analysis for these surfaces, yielding the T-4-adatom and twisted-adlayer models, respectively. Specifically, we show that one of the surface-shifted core-level C 1s peak s for the (root3 x root3)R30 degrees phase is contamination induced. Our hi gh-resolution electron energy loss spectroscopy experiments, which show a c hemical shift between the SiH stretch vibrations on the hydrogen exposed (r oot3 x root3)R30 degrees and (3 x 3) surfaces, are also consistent with the most recent structural models for these two surfaces, since they prove exc lusive silicon termination of both surfaces. (C) 2000 Elsevier Science B.V. All rights reserved.