The activation enthalpies for electron emission of 2 near T-site H centers in Si were determined to be about 0.65 and 0.79eV. The deeper center was O-related, and stabilized with a binding energy of about 0.5eV with respect to the shallower center. A negative-U behavior of both centers was verified, and the crucial effect that this behavior and the presence of O had on the migration of H in Si was demonstrated. The shallower center was interpreted as being the acceptor of monatomic isolated H, and the deeper center was interpreted as a perturbed version of this acceptor.

Acceptor State of Monoatomic Hydrogen in Silicon and the Role of Oxygen. K.Bonde Nielsen, L.Dobaczewski, S.Søgård, B.Bech Nielsen: Physical Review B, 2002, 65[7], 075205 (6pp)