Model of boron clustering in silicon

Abstract

The model of formation and dissolution of neutral boron clusters in silicon has been developed. Numerical calculations showed that the model proposed describes well the experimental data obtained for rapid thermal annealing. Agreement with experiment is observed for clusters incorporating a small number (2-3) of boron atoms. The assumption about the increasing rate of the reaction of cluster formation allows one to explain the experimentally observed phenomenon of the hole concentration saturation at a high doping level. The increase in the reaction rate is a result of the crystalline lattice deformation due to the mismatch between the boron and silicon atomic radii.