Thermal donor (TD) formation and nucleation of oxide precipitates at temperatures in a range of 350-800 deg C have been investigated in Czochralski silicon wafers which were beforehand subjected to rapid thermal annealing (RTA) at 1200 deg C in various atmospheres. The experimental results clearly indicated that hydrogen introduced by the RTA in H-2 atmosphere leads to both enhanced TD formation and enhanced precipitate nucleation at 350-450 deg C. An enhancement rate of the TD formation was found to be independent of initial concentration of interstitial oxygen. On the other hand, vacancy introduced by the RTA in N_2 atmosphere has no contribution to the TD formation, while that drastically enhances the precipitate nucleation at high temperatures, It is also suggested that the RTAs in H_2 and Ar atmospheres introduce a similar defect which enhances effectively the precipitate nucleation at 450-500 deg C. The nucertain defect has no influence on the TD formation so that the defect is not hydrogen-related.
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