Si Binding and Nucleation on Si(100)

Abstract

Si adatoms deposited on Si(100)-( $2\ifmmode\times\else\texttimes\fi{}1$) below $200{}^{\ensuremath{\circ}}$C assume metastable binding configurations, each distinct from the dimer string topology ordinarily observed following deposition at higher temperatures. Isolated ad-dimers which nucleate predominantly on substrate dimer rows at room temperature do not constitute the precursors for dimer strings. Instead, they transform upon annealing at $\ensuremath{\approx}$ $120{}^{\ensuremath{\circ}}$C to metastable, dimerized lines assembled end to end, parallel to the substrate's dimer bonds.