The formation behavior of grown-in voids during crystal growth was investigated for N-doped Czochralski Si crystals by means of a new quantitative defect evaluation method using a bright-field infra-red laser interferometer. Crystal quenching techniques were employed to study void formation and it was found that in crystals grown without N doping, the total amount of vacancies composing the voids did not change during the crystal growth halt. In N-doped crystals, however, the total number of vacancies composing the voids increased during the crystal growth halt. These results indicated that N made excess vacancies remain after void formation in crystals grown without a growth halt.

Nitrogen Effect on Grown-In Defects in Czochralski Silicon Crystals. S.Umeno, T.Ono, T.Tanaka, E.Asayama, H.Nishikawa, M.Hourai, H.Katahama, M.Sano: Journal of Crystal Growth, 2002, 236[1-3], 46-50