Laser annealing of diffusion-induced imperfections in silicon

High-temperature diffusion of boron or phosphorus into silicon leads to the formation of spherical precipitates and/or dislocation loops in the diffused layer which influence electrical junction characteristics. These diffusion-induced imperfections can be removed by high-energy pulse laser treatment. The boron or phosphorus atoms previously contained in the precipitates become electrically active and the resulting dopant concentration can exceed the solid solubility limit.