Plasma processing: a novel method to reduce the transient enhanced diffusion of boron implanted in silicon

In this paper a novel method is presented, based on the use of plasma proce ssing, to suppress the transient enhanced diffusion of boron implanted in s ilicon. We found for silicon samples processed with plasma and subsequently boron implanted that the anomalous diffusion of the dopant atoms at the be ginning of the annealing process is almost completely suppressed. This phen omenon is interpreted in terms of capture of the ion beam generated interst itials by the dislocations induced by the plasma processing. At room temper ature the dislocations are observed to grow in size after the boron implant , attesting their efficiency as trapping centres for interstitials. Moreove r, varying the plasma process conditions we can establish a general relatio n between the presence of the trapping centres induced by the plasma proces sing and the suppression of the transient diffusion. (C) 1999 Elsevier Scie nce B.V. All rights reserved.