Hydrogen interactions with interstitial- and vacancy-type defects in silicon

IR and EPR studies of hydrogen interactions with defects in silicon implant ed with protons and deuterons were carried out. An analysis of temperature dependence of Si-H local mode anharmonicity, using isotope substitution of H by D, revealed that anharmonicity is sensitive to the environment of a Si -H dipole. This enables to separate Si-H modes between H atoms in the vicin ity of vacancy or Si interstitial conglomerates and to construct models for I-I-related complexes. It is shown that the 2107, 2122 cm(-1) doublet may be assigned to V6H12, which can serve as nucleus of (1 1 1) platelets. Mech anisms of H interactions with ring hexavacancy and Si-B3 interstitial defec t are considered and tentative models for a new Si-AA17 EPR center and for H-related shallow donor suggested. (C) 1999 Elsevier Science B.V. All right s reserved.