Effect of oxygen concentration on the kinetics of thermal donor formation in silicon at temperatures between 350 and 500 °C

Early measurements of the initial rate of thermal donor formation in Czochralski silicon at 450 °C revealed a dependency on the fourth power of the oxygen concentration. This result has led to the view that the core of the defects contained four oxygen atoms. We now show that this dependency is observed only for anneals close to 450 °C. Our results indicate that oxygen dimerization controls the thermal donor formation kinetics but that the dimers become increasingly unstable above 400 °C.