Initial growth of Bi films on a Si(111) substrate: Two phases of √3 × √3 low-energy-electron-diffraction pattern and their geometric structures

Abstract

The ordering of Bi on a Si(111)-7\ifmmode\times\else\texttimes\fi{}7 surface was studied as a function of overlayer coverage and deposition conditions using low-energy-electron diffraction (LEED) and Auger electron spectroscopy. We observed a one-third-monolayer and a saturated one-monolayer phase. Both phases displayed identical \ensuremath{\surd}3 \ifmmode\times\else\texttimes\fi{} \ensuremath{\surd}3- R30\ifmmode^\circ\else\textdegree\fi{} LEED symmetries. LEED intensity data were used to differentiate between the two phases and to determine a quantitative atomic geometry via a thorough dynamical LEED analysis.