As-grown ingots of 4H-type material were investigated by means of diffraction imaging, using synchrotron radiation. White-beam sectional topographs, which were obtained for various sample geometries, permitted the detection of structural imperfections. The investigations indicated that observed inclusions of various polytypes in 4H-type ingots were related to an 8° off-axis orientation of the seed. These inclusions formed at the beginning of crystal growth and produced planar defects which propagated along the main vertical axis of the cylindrical crystal.

Structural Defects in SiC Ingots Investigated by Synchrotron Diffraction Imaging. E.Pernot, P.Pernot-Rejmánková, M.Anikin, B.Pelissier, C.Moulin, R.Madar: Journal of Physics D, 2001, 34[SA], 136-9