Dislocation core reconstruction in zinc-blende semiconductors

Using ab initio total-energy calculations, we computed core reconstruction energies of partial dislocations in zinc-blende semiconductors. The reconstruction energy of 30° partials was found to scale almost linearly with the experimental activation energy of 60° dislocations. The electronic structure of a dislocation shows that in an unreconstructed core, the gap states comprise a half-filled one-dimensional band, which splits up into bonding and antibonding states upon reconstruction. The energy states which lie in the electronic gap come from the core of β-partials, while those related to α-partials remain resonant in the valence band.