SI(100)1X1-SB AND SI(100)2X1-SB SURFACES STUDIED WITH ANGLE-RESOLVED PHOTOEMISSION AND SURFACE DIFFERENTIAL REFLECTIVITY

Angle-resolved Photoelectron spectroscopy and surface differential reflectivity have been used to study the electronic structure of Si(100):Sb-1 X 1 and Si(100):Sb-2 X 1 surfaces. For both surfaces, one occupied surface-state band has been mapped along the [010] and [011] directions. Both surfaces show a semiconducting behavior with a gap of 1.6 eV for the 1 X 1-Sb and 1.4 eV for the 2 X 1-Sb surface. A minimum-energy position at the Fermi level is derived for the empty surface-state band. The results are also compared with those obtained for the clean Si(100)2 X 1 surface.