The energetics of dislocation cores in semiconductors and their role on dislocation mobility

We investigated core properties of dislocations in zinc-blende semiconducto rs using ah initio total energy calculations. The core reconstruction energ y of partial dislocations was found to scale almost linearly with the exper imental dislocation activation energy. The electronic band structure relate d to dislocation cores was also determined. In an unreconstructed core, the gap states comprise a half-filled one-dimensional hand, which splits up in bonding and antibonding states upon reconstruction. The energy states whic h lie in the electronic gap come from the cores of beta partials, while tho se related to alpha partials remain resonant in the valence band. (C) 2001 Elsevier Science B.V. All rights reserved.