Structure of copper precipitates in a symmetrical silicon tilt bicrystal : high-resolution electron microscopy and energy-dispersive X-ray analysis

Abstract Precipitates have been found in silicon bicrystals after heat treatments. Most of them are localized in the grain-boundary (GB) plane where they form disc colonies. The GB precipitates have been examined using conventional electron microscopy, high-resolution electron microscopy and energy-dispersive X-ray analysis techniques. They contain a large amount of copper. The structure of the precipitates in the GB is b.c.c. and is likely to be disorderd. The grain-precipitate epitaxy relationship has been determined. A mechanism for the copper precipitation in disc colonies along the GB is proposed.