The role played by F in the reduction of self-interstitial populations in a pre-amorphized Si layer under thermal treatment was explained. For this purpose, a B spike layer grown by molecular-beam epitaxy was used as a marker for the self-interstitial local concentration. The amorphized samples were implanted with 7 x 1012, 7 x 1013 or 4 x 1014F/cm2 at 100keV, and afterwards recrystallized by solid phase epitaxy. Thermal anneals at 750 or 850C were performed in order to induce the release of self-interstitials from the end-of-range defects and thus provoke the transient enhanced diffusion of B atoms. It was shown that the incorporation of F reduced the B-enhanced diffusion in a controlled way; up to complete suppression. It was seen that no direct interaction between B and F occurred, whereas the suppression of B-enhanced diffusion was related to the F ability to reduce the excess of Si self-interstitials emitted by the end-of-range source.

Role of Fluorine in Suppressing Boron Transient Enhanced Diffusion in Pre-Amorphized Si. G.Impellizzeri, J.H.R.dos Santos, S.Mirabella, F.Priolo, E.Napolitani, A.Carnera: Applied Physics Letters, 2004, 84[11], 1862-4