Transmission electron microscopy, high-resolution X-ray diffraction, and KOH etching were used to study dislocation structures in 4H-type crystals which had been grown by means of vapour transport. Many of the etch pits on the Si(00•1) surface formed arrays which extended along the <¯11•0> directions. Plan-view conventional and high-resolution transmission electron microscopy showed that the arrays consisted of pure edge dislocations which threaded along the c-axis, with identical Burgers vectors of a/3<11•0>-type. The dislocation arrays constituted low-angle [00•1] tilt boundaries. That is, [00•1] was the common axis lying in the boundary. The misorientation was typically in the 60 to 200arcsec range. Such boundaries could form via polygonization of threading edge dislocations which were introduced into SiC crystals by prismatic slip.

Origin of Domain Structure in Hexagonal Silicon Carbide Boules Grown by the Physical Vapour Transport Method. S.Ha, N.T.Nuhfer, G.S.Rohrer, M.De Graef, M.Skowronski: Journal of Crystal Growth, 2000, 220[3], 308-15