Surface reconstruction on Si(100) studied by the CNDO method

Abstract

The authors have examined seven reasonable asymmetrical dimer configurations for a Si(100) surface using the CNDO method. In this work, all structures resulting from higher-order dimer reconstruction are named according to Pauling and Herman's terminology. Reconstructed 4*1 and 4*2 surfaces are found to be energetically more favourable, followed by 2*2A and 2*1. The total energies per dimer of these four structures are reasonably close to each other and a disordered mixture of them might appear at the Si(100) surface. The results agree well with previous theoretical work as well as with experimental results. However, the 4*1 configuration cannot be confirmed as it has not been observed experimentally. The results on the amount of charge transfer to the dimer atoms and the dimer lengths for each configurations are also presented.