VALENCE AND ATOMIC SIZE-DEPENDENT EXCHANGE BARRIERS IN VACANCY-MEDIATED DOPANT DIFFUSION

First-principles pseudopotential calculations of dopant-vacancy exchan ge barriers indicate a strong dependency on dopant valence and atomic size, in contrast to current models of vacancy-mediated dopant diffusi on, First-row elements (B, C, N) are found to have exchange barriers w hich are an order of magnitude larger than the assumed value of 0.3 eV (the Si vacancy migration energy), (C) 1998 American Institute of Phy sics. [S0003-6951 (98)04128-X].