The structural properties of sub-grain (low-angle) grain boundaries in bulk crystals were studied by using high-resolution X-ray diffraction and molten KOH etching. The latter revealed that the sub-grain boundaries were polygonized in <1¯1•0> directions, and usually occurred at the periphery of crystals. The relative misorientation between adjacent sub-grains was examined by high-resolution X-ray diffraction, and it was found that tilting of the (00•1) lattice plane occurred at the sub-grain boundaries and had a rotation axis which was parallel to both the boundary plane and the (00•1) basal plane.

Structural Properties of Sub-Grain Boundaries in Bulk SiC Crystals. M.Katsuno, N.Ohtani, T.Aigo, T.Fujimoto, H.Tsuge, H.Yashiro, M.Kanaya: Journal of Crystal Growth, 2000, 216[1-4], 256-62