Evaluating the effects of internal gettering in epi Si

A rigorous study of the efficiency of internal gettering under different conditions, comparing it to external and p(+) gettering, has shown it to be effective in p(+) substrates with backside polysilicon. This is true when the density of oxygen precipitates is high and their size small. However, internal gettering is not effective for a low density of oxygen precipitates when using either p(+) substrates or polysilicon.