Anomalous phosphorous diffusion

It has been found that P diffuses anomalously at low temperatures in heavily doped regions with doping concentration greater than 7/spl times/10/sup 20/ cm/sup -3/. Furthermore, it was found that the anomalous diffusion continues for a certain time period which cannot be suppressed by high-temperature annealing. We evaluated the prominent parameters associated with this anomalous diffusion, the diffusion coefficient, and the time period of this diffusion. We have also succeeded in describing the thermal budget associated with it.