Electron beam-induced current measurements were carried out on  = 25,  = 13 and  = 9 bicrystals. A comparative study was made of the gettering effects of twin boundaries in bicrystals which were pre-contaminated with Ni. The NiSi2 particles were found to account for a marked electrical activity in the bulk and for a notable increase in the electron beam-induced current contrast at grain boundaries. Contrast differences which were noted at the level of  = 25 (uniform),  = 13 (uniform and dotted) and  = 9 (dotted only) grain boundaries were found to originate from the various microstructures of these interfaces, which appeared to govern the precipitation process. The gettering efficiency of each boundary was associated with the extent of the denuded zone which appeared on each side of the grain boundary. This zone attained some 150 in the case of  = 25, and about 120 in the case of  = 13. It was indiscernible in the case of  = 9. This scaling in the gettering efficiencies was related to a similar ranking of the calculated energy of the associated boundary.

A.Ihlal, R.Rizk, P.Voivenel, G.Nouet: Journal de Physique III, 1995, 5[9], 1371-82