Various point defects were studied theoretically from the point view of positron annihilation spectroscopy. The properties of a positron which was trapped at a single vacancy, divacancy, vacancy-O complex or divacancy-O complex were investigated. In addition to the positron lifetime and positron binding energy to defects, calculations were also made of the momentum distribution of annihilation photons of high momenta; which were useful for defect identification in semiconductors. The effect of atomic relaxations, around defects, upon positron properties was also examined. The mutual differences among the high-momentum parts of the momentum distribution of annihilation photons for various defects were generally considerable.

Vacancies and vacancy-oxygen complexes in silicon J.Kuriplach, A.L.Morales, C.Dauwe, D.Segers, M.Sob: Physical Review B, 1998, 58[16], 10475-83