AVS 46th International Symposium
    Surface Science Division Wednesday Sessions
       Session SS3+EM-WeM

Paper SS3+EM-WeM5
Low Temperature Scanning Tunneling Microscopy and Spectroscopy of the @sr@3x@sr@3 R30° Phase of Sn/Si(111)

Wednesday, October 27, 1999, 9:40 am, Room 604

Session: Surface Electronic Structure
Presenter: L. Ottaviano, INFM, Italy
Authors: L. Ottaviano, INFM, Italy
A. Continenza, University of L'Aquila and INFM, Italy
M. Crivellari, University of L'Aquila and INFM, Italy
L. Lozzi, University of L'Aquila and INFM, Italy
S. Modesti, University of Trieste and Laboratorio TASC-INFM, Italy
S. Picozzi, University of L'Aquila and INFM, Italy
G. Profeta, University of L'Aquila and INFM, Italy
S. Santucci, University of L'Aquila and INFM, Italy
Correspondent: Click to Email
In these years there has been a great deal of efforts in the understanding of the low temperature transition from a @sr@3x@sr@3 R30° to a 3x3 phase of Sn(Pb)/Ge(111).@footnote 1@,@footnote 2@ On the other hand, little attention has been devoted to the investigation of iso-electronic interfaces like Sn(Pb)/Si(111) at similarly low temperatures. Among other experimental techniques, STM can provide a deep understanding of the electronic structure of these surfaces by performing measurements at various tunnelling voltages. Theorist who proposed different model interpretations have recently called for STM experiments at low temperatures on such systems.@footnote 3@ We show the first STM atomically resolved images of the low temperature (100 K) 1/3 ML-Sn/Si(111) @sr@3x@sr@3 R30° phase. Correspondingly we have measured tunnelling I-V spectra. Data are compared with all electron ab-initio calculations performed on a slab of Si(111) covered with 1/3 ML-Sn in the @sr@x@sr@3 R30° reconstruction. In particular we compare the ab-initio results with surface and electronic properties as obtained by STM/STS and photo-emission results. @FootnoteText@ @footnote 1@ L.Petaccia, L.Grill, M. Zangrando, and S. Modesti, Phys. Rev. Lett. 82 (1999) 386. @footnote 2@ A. Mascaraque et al., Phys. Rev.Lett. 82 (1999) 2524. @footnote 3@ S. Scandolo, F. Ancilotto, G.L.Chiarotti, G. Santoro, S. Serra, and E.Tosatti, Surf. Sci. 402-404 (1998) 808.