STRUCTURAL STUDY OF A COMMENSURATE PHASE AT CO/SI(111) INTERFACE USING IN SITU SURFACE X-RAY SCATTERING

Abstract

Interfacial structure and reaction stoichiometry of the Co-adsorbed Si(111) surface at room temperature has been studied by in situ synchrotron surface x-ray scattering. The intensity oscillation at the anti-Bragg position of the (1,0) off-specular crystal truncation rod indicates a layerwise consumption of silicon substrate during the deposition of the first 15 Co monolayers. Our data suggest that an interfacial silicide layer formed in the initial stage of growth have the atomic stoichiometry of Co2Si. The silicide layer is a commensurate phase of pseudohexagonal Co2Si, which shows a long-range order with large strain imposed by the Si substrate. (C) 2002 American Institute of Physics.