Stress relief from reconstructions on SbÕSi„001..

The structures and stress of the Sb/Si~001! surface have been studied by a semiempirical tight-binding Green’s function method. The Sb/Si(001)231 surface is found to be under a tensile stress of 1.0 eV/(131 cell! along the dimer bond and a compressive stress of 21.1 eV/(131 cell! along the dimer row. Calculations of the surface stress for Sb/Si~001! (234), (235), and (236) reconstruction, which is formed by shifting dimers in the dimer row to the adjacent trench, show a significant relief of the compressive contribution to the stress along the dimer row comparing with the case of the (231) reconstruction, and thus a decrease of the stress anisotropy.