ELECTRONIC STRUCTURE OF THE Si(111) $\sqrt 3 \times \sqrt 3 $ SURFACES WITH GROUP-III, IV, AND V ADATOMS

Abstract

A review is presented for the theoretical aspects of electronic structure and stable atomic geometry of group-III, IV, and V adatoms on the Si(111) surface. After summarizing the general concepts of surface electronic structure, we present preliminary studies based on the elementary theory of covalent bond, to understand the features of surface states and the relative stability of various candidates for adsorption geometries. Results of recent numerical calculations are then reviewed for three typical adatoms: Al, Sb, and B, in which we show how they give consistent conclusions with experimental findings.