Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms vol:76 issue:1-4 pages:434-436
Mossbauer spectroscopy was used to study the formation and stability of Co-acceptor complexes after diffusion of Co-57 in heavily B-, Al-, Ga- and In-doped silicon. The Fe-57 MS-spectra recorded after diffusion and quench show a dominating line complex (with an absorber isomer shift between +0.7 and +1.0 mm/s relative to alpha-Fe), previously attributed to Co-acceptor pairs. Upon annealing a transformation of this Co-complex is observed, and activation energies are derived in the range of 1.4 to 1.8 eV, much larger than expected for the dissociation of Co-acceptor pairs. Possible reasons for this discrepancy are discussed.