Formation of Fei-B pairs in silicon at high temperatures

We report on the detection of Fei-B pairs in heavily B doped silicon using 57Fe emission Moessbauer spectroscopy following implantation of radioactive 57Mn+ parent ions (T1/2 = 1.5 min) at elevated temperatures > 850 K. The Fei-B pairs are formed upon the dissociation of Fei-V pairs during the lifetime of the Moessbauer state (T1/2 = 100 ns). The resulting free interstitial Fei diffuses over sufficiently large distances during the lifetime of the Moessbauer state to encounter a substitutional B impurity atom, forming Fei-B pairs, which are stable up to ∼1,050 K on that time scale.