Mechanism of Reconstruction of Si(100) Surfaces

Electronic structures of Si(100) buckled 2×1, p(2×2) and c(4×2) surfaces are revealed by first-principles LDA calculation. The c(4×2) surface is found to be the most stable structure. The mechanism of the stabilization for this surface is different from the electrostatic dipole-dipole interaction of the asymmetric dimers. The dispersion of the surface band compares fairly well with the ARUPS observation. The theoretical simulations of STM image for Si(100) surface is described.