Iron precipitation in as-received Czochralski silicon during low temperature annealing

The iron precipitation in as-received Czochralski (CZ) silicon during low temperature from 300 to 700 °C was investigated. It was found that the iron precipitation rate was increased in turn from 300 to 700 °C. It was also found that the iron could form small precipitates even at low concentration. Moreover, iron precipitation was revealed as the diffusion-limited process, which could be described properly by Ham's law. This performance of iron precipitation in as-received CZ silicon was considered to be significantly influenced by the grown-in oxygen precipitates because of the fact that the grown-in oxygen precipitates could act as the heterogeneous nuclei for interstitial iron.