Scanning infra-red microscopy, Fourier-transform infra-red spectroscopy, light beam-induced current mapping, diffusion length measurements and chemical etching were used to detect precipitates in annealed Czochralski wafers and to control their interaction with self-interstitials that were injected into the bulk by P diffusion or oxidation. The diffusion of Cu was also carried out in order to study the effect of metallic contamination. Following nucleation annealing (750C) and/or growth annealing (900C), P diffusion annealing (900C, 4h) shrank the precipitates which were revealed by means of scanning infra-red microscopy. This shrinkage was attributed to a marked injection of self-interstitials into the bulk. Annealing of the 2-step annealed samples in O produced a similar effect. However, new defects were detected by means of scanning infra-red microscopy and were identified as being stacking faults.

C.Veve, S.Martinuzzi: Semiconductor Science and Technology, 1996, 11[12], 1804-14