Dislocation core properties in semiconductors

Abstract

Using ab initio calculations, we computed the core reconstruction energies of {111} 30° partial dislocations in zinc-blende semiconductors. Our results show a direct correlation between core reconstruction energies and the experimental activation energies for the velocity of 60° dislocations. The electronic structure of unreconstructed dislocation cores comprises a half-filled band, which splits up in bonding and antibonding levels upon reconstruction. The levels in the electronic gap come from the core of β dislocations, while the levels related to α dislocations lie on the valence band.