SCANNING TUNNELING SPECTROSCOPY EXAMINATION OF SURFACE ELECTRONIC-STRUCTURES OF SI(111)(2-ROOT-3X2-ROOT-3)30-DEGREES-SN SURFACE

Scanning tunneling spectroscopy (STS) measurements have been performed on Si(111)(2 root x 2 root 3)30 degrees-Sn surface. Tunneling spectra l analysis of the energy of the surface states around the Fermi-level (E(f)) indicates two filled and two empty states straddling E(f), show ing a similar to 1.6 eV surface bandgap. As part of the identification of these surface states, STS spectra were also taken on a coexisting well-known root 3 x root 3 surface, and the intrinsic nature of these surface states is discussed.