Multi-chroic infra-red light scattering tomography and transmission electron microscopy were used to systematically investigate the inhomogeneous radial distribution of defects in as-grown and annealed Czochralski Si crystals. A new defect morphology of dark stripes observed for the first time by the multi-chroic infra-red light scattering tomography system in a special region of the as-grown crystal. After annealing (1150C, 16h, O2 atmosphere), dark stripes that became scattered in width and deep in contrast were clearly visible in an OSF-ring area. The location of these stripes in the as-grown crystal coincided with that in the annealed CZ-Si crystal, where many stacking faults and

O-precipitate-related polyhedral defects were revealed by transmission electron microscopic analysis. This means that the dark stripes were generated during crystal growth as original grown-in defects. Quantitative measurement of the inhomogeneous radial distribution of defects in the annealed crystal was made and the characteristics of the defects in different regions of the crystal were analyzed.

Study of Inhomogeneous Radial Distribution of Defects in As-grown and Annealed Czochralski Silicon Crystals by Multi-chroic Infrared Light Scattering Tomography. M.Ma, T.Irisawa, T.Ogawa, C.Frigeri: Japanese Journal of Applied Physics - 1, 2001, 40[6A], 4153-9