Optimum widths of dimer vacancy lines on Si(100)-(2×1)

Abstract

We have used the ab initio multicenter molecular-dynamics method to calculate the surface energies of dimer vacancy lines (DVL's) formed on the Si(100)-(2\ifmmode\times\else\texttimes\fi{}1) surface as a result of sputtering or etching. Our results show that the optimum widths of the DVL's perpendicular to the dimer rows are two and three missing dimers. Our results also show that at higher vacancy concentrations, DVL's parallel to the dimer rows (sometimes also known as ``vacancy islands'') with widths greater than three missing dimers are favored over the perpendicular DVL's. Both of these results are in agreement with experimental observations.