Boron non-uniform precipitation in Si at the Ostwald ripening stage

The numerical model based on the Ostwald ripening theory is proposed for a non-uniform ensemble of precipitates. The model describes the boron precipitate ensemble layering in Si highly boron pre-doped then highly boron implanted and then high temperature annealed. To make the classical Ostwald ripening model consistent with the experimental data we had introduced three additions in the model. First one concerns the initial distributions of self-interstitials, boron atoms in substitutional positions, and precipitates. Second one declares that the growth/dissolution of precipitates starts gradually from the edges of implanted layer toward Rp. Third one takes into account the enhancement of boron diffusivity in layers with growing precipitates. The adopted model agrees well with experimental data. (C) 2009 Elsevier B.V. All rights reserved.