Normal, cusp magnetic field and electromagnetic field Czochralski methods were used to grow crystals, and the behaviours of defects in the crystals were investigated by using a new detection method which involved multichroic infra-red light scattering tomography. The results showed that the defect density and distribution in the 3 types of crystal were clearly different due to the differing physical conditions: such as melt flow in the crucible and temperature fluctuations in the melt during growth. A lower defect density was observed in crystals which were grown under a cusp magnetic field or electromagnetic field. A one-to-one relationship was observed between white defect spots in light-scattered images and dark spots in photoluminescence images. The defects were of interstitial type and formed dislocation clusters and dislocation lines.

Study on Defects in Cz-Si Crystals Grown by Normal, Cusp Magnetic Field and Electromagnetic Field Techniques Using Multi-Chroic Infrared Light Scattering Tomography. M.Ma, T.Irisawa, T.Tsuru, T.Ogawa, M.Watanabe, M.Eguchi: Journal of Crystal Growth, 2000, 218[2-4], 232-8