In order to better understand internal gettering of iron in silicon at low supersaturation, an experimental study of iron gettering with different annealing profiles was performed. Special attention was paid to the effect of iron nucleation at low temperatures. The results reveal that gettering can be efficient even after 30 minutes anneal at 700°C if the wafers go through a low-temperature region before the actual gettering anneal. In the simplest case the low-temperature nucleation can be realized by a fast withdrawal of the wafers out of the furnace. The density of oxygen precipitates seemed to have only a minor impact on the gettering efficiency indicating that not every oxygen precipitate related gettering site is an active sink for iron.
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