Structure, stability, and origin of (2perp) phases on Si(100).

Abstract

Phases with ($2\ifmmode\times\else\texttimes\fi{}n$) structure ($6<n<10$) can be formed on Si(100) by rapid quenching from high temperatures. The nominal (2\ifmmode\times\else\texttimes\fi{}7) phase has been investigated by high-resolution low-energy electron diffraction. The structure involves two atomic levels, is metastable, and decays with first-order kinetics. The structure can be explained by ordering of excess missing-dimer defects, which apparently are present on the surface with any of the standard surface preparation techniques for Si(100).