A study was made of the defects which were introduced by irradiation, quenching and crystal growth in Czochralski-type crystals. Measurements of lifetime and Doppler broadening of positron annihilation clarified the annealing behavior of the irradiation defects. The results of the irradiation studies were used to analyze the defects which were formed by quenching, and those which formed during crystal growth. It was found that O clusters were formed by quenching, and that the O clusters were introduced in association with stacking-fault nuclei during crystal growth.

A.Ikari: Applied Surface Science, 1995, 85, 253-8