Determination of the criteria for nucleation of ring-OSF from small as-grown oxygen precipitates in CZSi crystals

The behaviour of small as-grown platelet-type oxygen precipitates, known to nucleate ring-like distributed oxidation induced stacking faults (ring-OSF), was studied in CZSi crystals grown with modulating growth rates using IR light scattering tomography, μ-photoconductive decay lifetime analysis and preferential etching. It was found that although these oxygen precipitates were observed on the ring region, their OSF nucleation ability differed greatly depending on the crystal growth conditions. We propose that the OSF nucleation ability of an oxygen precipitate depends on its size, and in order for successful OSF nucleation, the precipitate size must lie within certain limits. Using the difference in the thermal histories of the crystals grown with modulating growth rates, we calculated that only platelet-type oxygen precipitates on the ring-OSF region having a length between 260 and 1350Åare capable of OSF nucleation.