IMPLANTATION AND TRANSIENT BORON-DIFFUSION - THE ROLE OF THE SILICON SELF-INTERSTITIAL

The phenomena associated with the transient diffusion of implanted B i n Si are reviewed. The Si self-interstitial flux, which causes the B i nterstitialcy diffusion, has been directly observed by the use of B di ffusion marker layers fabricated by low-temperature crystal growth. Lo w-energy and low-dose Si implants in surface layers permit the experim ental separation of the source and flux of interstitials. The clusteri ng of B is directly correlated with the supersaturation of injected Si interstitials. The diffusivity of the Si interstitial is dominated by the presence of trapping sites. Implantation produces rod-like defect s which consist of interstitial precipitates on {311} planes as a sing le monolayer of hexagonal Si. The number of Si interstitials evaporati ng from the {311} defect is sufficient to explain the whole of the tra nsient diffusion.