- Tan, T.Y., Intrinsic gettering in Czochralski silicon,
Proceedings of the Second Symposium on Defects in Silicon. Defects in Silicon II
pp. 613 - 30 .
(last updated on 2007/04/10)
The basic physical aspects of intrinsic gettering are first reviewed and then some still outstanding questions discussed. In supersaturation at the processing temperatures, oxygen (Oi) in CZ Si bulk forms SiO2 precipitates which generate dislocations. The precipitate-dislocation complexes are gettering centers of metallic impurities. At the wafer surface regions oxygen diffuses out to yield a defect-free zone (DFZ) suitable for device fabrications. For successful applications, DFZ and bulk precipitate production must be carefully controlled. This is related to SiO2 precipitate nucleation and growth processes that are associated with an extremely large volume expansion, which is manifested by the existence of very complicated experimental results particularly when carbon is also involved. The involved issues have been so far only partially resolved within the framework of dynamical equilibrium between Oi supersaturation and resulting Si self-interstitial I