Samples were Au-diffused at 870 to 950C, and implanted with 1.6MeV He ions to fluences ranging from 2 x 1016 to 1017/cm2. The implantation-induced defects which were observed by conventional and high-resolution cross-sectional electron microscopy were found to be essentially cavities, 10 to 100nm in size, which were faceted mainly on {111}, but also on {110} and {100) planes. The cavities were located at the depth which was predicted by the transport range of ions in simulations. Secondary ion mass spectroscopic profiles had a shouldered shape, with a maximum at the projected range. They demonstrated that the cavities were very efficient sinks for Au atoms; the shoulder of the profile being related to the presence of smaller cavities and dislocations in the vicinity of the projected range.

Gettering of Diffused Au and of Cu and Ni Contamination in Silicon by Cavities Induced by High-Energy He Implantation. R.E.Bouayadi, G.Regula, B.Pichaud, M.Lancin, C.Dubois, E.Ntsoenzok: Physica Status Solidi B, 2000, 222[1], 319-26