Theoretical study of surfactant action of Te on Si(001)/Ge surfaces

Abstract

We h a ve performed rst-principles total energy calculations to investigate the adsorption process of Ge on Si001 Te, and the surfactant action of Te during the epitaxial deposition of Ge on Si001 Te, based on an atomic exchange process, Ge$Te. The total energy calculation indicates that the adsorption of Ge atom in vacancy" site is energetically more favourable than its adsorption in bridge" site. The adsorption of Ge in on-top" and anti-bridge" sites can be ruled out. The segregation process of Te atoms, based on an atomic exchange mechanism, reduces the total energy of the surface, con rming the surfactant e ect of Te atoms.