Effect of Thermal History on Iron Precipitation in Crystalline Silicon

We have studied the effect of thermal history on iron precipitation behavior in intentionally contaminated Czochralski silicon wafers that contain well-defined precipitation sites for iron, oxide precipitates. Iron precipitation was studied at a temperature range between 600°C and 700°C for various times. The results indicate that iron precipitation is strongly affected by the thermal history of the wafers. Our results also explain the disagreement observed previously in iron precipitation behavior at low temperature anneals. Finally, we discuss how the results can be applied to gettering in multicrystalline silicon.