Two FeH pairs in n-type Si and their implications:: A theoretical study

Experimental evidence for interstitial {FeH} pairs in n-type Si stems from thermally stimulated capacitance (TSCAP). Electron- paramagnetic resonance (EPR) data have also been interpreted in terms of {FeH} pairs. We present theoretical studies of two {FeH} pairs. The properties of the first match those of the TSCAP center but are incompatible with the EPR center. The second is a possible candidate for the EPR center. If true, this suggests that high-temperature anneals can introduce substitutional Fe in concentrations higher than commonly believed.