Indium-induced reconstructions of the Si(100) surface

Abstract

The behavior of indium on the Si(100)2\ifmmode\times\else\texttimes\fi{}1 surface has been studied using scanning tunneling microscopy. At temperatures below 150mDC, low coverages of In form dimer rows that are oriented perpendicular to the underlying Si dimer rows. As the coverage increases, these rows pack into areas of two-dimensional order, forming the 2\ifmmode\times\else\texttimes\fi{}2 reconstruction at 0.5 ML. For substrate temperatures above 150\ifmmode^\circ\else\textdegree\fi{}C, low coverages of In form isolated structures which have two maxima in the empty electronic states and a central maximum in the filled states. As the coverage increases, these In structures arrange into rows oriented parallel to the Si dimer rows with an inter-row spacing of four unit cells. At 0.5 ML, the In structures are spaced three unit cells apart along these rows, thus forming the In(4\ifmmode\times\else\texttimes\fi{}3) reconstruction. Evidence for disruption of the substrate Si dimer bonds and Si displacement due to formation of the 4\ifmmode\times\else\texttimes\fi{}3 phase is also observed.