INTERSTITIAL-O IN SI AND ITS INTERACTIONS WITH H

Interactions between interstitial H and interstitial O in crystalline silicon have been studied at the approximate ab initio (parameter-free) Hartree-Fock level in three clusters containing 5, 26, and 35 host atoms, respectively. The key results are (1) no configurations with significant O-H bonding are energetically favorable and (2) the activation energy for diffusion of interstitial O is considerably lower when H is present than when it is not. It is estimated that H enhances the diffusivity of interstitial O by several orders of magnitude. The results provide insights into the interpretation of the recently observed enhancement by atomic hydrogen of the rate of formation of thermal donors in silicon. © 1990 The American Physical Society.