Arrays of dislocations were investigated, in float-zone wafers, by using the light beam-induced current mapping technique at various wavelengths, and by using deep-level transient spectroscopy. The former technique permitted the recognition and detection of the arrays and the evaluation of their recombination strength. It was found that the dislocations were less recombining in (100)-oriented samples than in (111)-oriented samples. In these dislocated float-zone wafers, the occurrence of P diffusion attenuated the light beam-induced current contrast of the dislocations to an extent which depended upon the duration and temperature of the treatment. The electrical activity of the defects, which were still present (as shown by X-ray topography), seemed to disappear. At the same time, the peak intensities of the deep-level transient spectra which were related to dislocations were weakened to an extent that depended upon the temperature and duration of P diffusion.

J.J.Simon, I.Périchaud, N.Burle, M.Pasquinelli, S.Martinuzzi: Journal of Applied Physics, 1996, 80[9], 4921-7