Atomically resolved tunneling spectroscopy on -M. Schöck1, 2, C. Sürgers1 and H. v. Löhneysen1, 3
1 Physikalisches Institut and Center for Functional Nanostructures Universität Karlsruhe - D-76128 Karlsruhe, Germany
2 Forschungszentrum Karlsruhe, Institut für Nanotechnologie D-76021 Karlsruhe, Germany
3 Forschungszentrum Karlsruhe, Institut für Festkörperphysik D-76021 Karlsruhe, Germany
received 6 February 2006; accepted 1 March 2006
published online 22 March 2006
The Si(557)-Au one-dimensional surface structure, with two types of characteristic protrusions denominated as alternating chains and rows oriented parallel to the [ ] direction, is investigated at room temperature by scanning tunneling microscopy and spectroscopy in order to determine the local electronic properties. Tunneling spectra taken with atomic resolution above the two substructures are different which demonstrates that they arise from different contributions of the surface band-structure, i.e. Si adatoms and step edges. We find no evidence for features originating from Au atoms, indicating that these are completely embedded in the surface, in agreement with recent structure models.
68.37.Ef - Scanning tunneling microscopy (including chemistry induced with STM).
73.20.At - Surfaces states, band structure, electron density of states.
81.07.-b - Nanoscale materials and structures: fabrication and characterization.
© EDP Sciences 2006