Inelastic low-energy electron diffraction from a silicon (111) 7 × 7 surface

Abstract

Inelastic low-energy electron diffraction from a silicon (111) 7 × 7 surface can be explained in terms of transitions from an occupied state, observed in photoemission, to unoccupied states whose existence is observed or implied from secondary electron emission. The density of states of the surface-state conduction band is reported. This band extends from 2.3 to about 12 eV above the top of the valence level, with a maximum density at 7 eV. A surface exciton is observed at 1.9 eV.