Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms vol:120 issue:1-4 pages:51-55
The trapping of transition metal impurities to cavities in c-Si recently attracted much interest, stemming from the possibility to use the process for proximity gettering. Mossbauer spectroscopy is employed on ion-implanted Co-57/Fe-57 to elucidate the nature of the site of the impurity atom at the internal surface of the voids. We observe a trapping effect upon thermal treatment, hampering normal silicide formation. Also a pre-existing silicide phase can be partially dissolved in favour of cavity trapping. The binding energy for cavity trapping is found to be lower than for silicide formation.