The behavior of defects which were detected by means of light-scattering tomography after annealing, and which were located between 0 and 20 beneath the surface of wafers, was investigated. The defects were detected by using the oblique-incidence method of infra-red light-scattering tomography, before and after annealing at temperatures between 1000 and 1280C in dry O, N or H. The defects remained after annealing for 4h at temperatures below 1250C in dry O or N, and disappeared after annealing at 1280C. However, after annealing at 1180C for 2h in H, defects which were located at between 0 and about 6 below the wafer surface disappeared, while those which were deeper than about 6 beneath the surface remained.

J.Furukawa, N.Iwaoka, H.Furuya: Materials Science Forum, 1995, 196-201, 1725-30