Computer simulation of oxygen precipitation in CZ-silicon during rapid thermal anneals

A new computer model for the simulation of oxygen precipitation in conventional as well as rapid thermal anneals is presented. The kinetic part of the model combines chemical rate equations and a Fokker-Planck equation. This allows for an adequate description of both small and larger precipitate sizes. The model cran be fitted to experimental data reported by Hawkins and Lavine [1] concerning reduction of interstitial oxygen after a 950°C/1h - 1200°C/10h annealing cycle. If the annealing cycle is preceded by a short therma1 pulse (1200°C/2s)) retardation of oxygen precipitation is observed experimentally. In our simulations this can be explained by t he dissolution of small precipitates, which have formed during crystal growth.