Evidence for a dimer reconstruction at a metal-silicon interface

We show that the stable structure of a CoSi₂/Si(001) interface involves a 2×{}1 periodic array of Si dimers with bond length 0.23±{}0.02 nm. We use a novel combination of quantitative transmission-electron diffraction, transmission-electron-microscope (TEM) imaging, and high-resolution TEM to solve the structure and have imaged separate 2×{}1 and 1×{}2 domains, {~}100 nm in size, over many {μ}m² of the interface.