The selectivity of interstitial-based extended defects (loops) and nano-cavities, for the gettering of Cu and Fe in Si, was studied. Controlled amounts of Cu and Fe were ion-implanted into wafers which contained pre-existing nano-cavities and/or dislocations. The results showed that Cu had a strong preference for gettering to open-volume defects; even when high concentrations of interstitial-based loops existed in close proximity. However, the gettering of Fe in samples which contained both vacancy-type and interstitial-type defects was more complex; with Fe accumulation in all regions of a defect-containing sample, regardless of whether they were vacancy-like or interstitial-like.

Selectivity of Nanocavities and Dislocations for Gettering of Cu and Fe in Silicon. B.Stritzker, M.Petravic, J.Wong-Leung, J.S.Williams: Applied Physics Letters, 2001, 78[18], 2682-4