Surface core-level shifts of Si(111)7×7: A fundamental reassessment

Abstract

Extremely well resolved Si 2p core-level spectra from the clean Si(111)7\ifmmode\times\else\texttimes\fi{}7 surface have been obtained at \ensuremath{\sim}100 K. Surface-shifted components become visible to the naked eye. Contributions from the constitutive entities of the complex 7\ifmmode\times\else\texttimes\fi{}7 reconstruction, i.e., rest atoms, adatoms, pedestal atoms, and dimer atoms are clearly identified. This puts into new perspective the spectroscopy and physics (structure and electronics) of this prototypical surface.