A tight-binding total-energy investigation was made of the ordering of dimer vacancies, especially dimer-vacancy line defects, on the (100) surface. It was found that a dimer-vacancy line which formed perpendicular to the direction of the surface dimer row was energetically favourable at low vacancy concentrations. However, at higher vacancy concentrations, the dimer-vacancy line was aligned parallel to the direction of the surface dimer row. Possible routes to line-defect formation via the diffusion of dimer vacancies were considered. The calculated results were in good agreement with experiment.

Ordering of Dimer Vacancies on the Si(100) Surface E.Kim, C.Chen, T.Pang, Y.H.Lee: Physical Review B, 1999, 60[12], 8680-5