The electronic structure of the (111) surface of silicon

Abstract

In this letter results are presented of a new study of the electronic structure of semiconductor surfaces. Optical data were used to obtain the Slater-Koster parameters of the tight-binding bandstructure for silicon, and these parameters have been used to study the bulk and (111) surface region of silicon. The main conclusion is the existence of only one surface state per atom concentrated just below the bottom of the absolute bandgap, and with a localization of two atomic layers (a half-length of 2.1 AA), while the competition between the termination of bulk states and the decay of surface states gives rise to lesser features throughout the valence band and lowest conduction band.