It was noted that the dislocations visible in X-ray topographs of as-grown hexagonal Lely platelets, and physical vapor transport-grown wafers, extinguished as if they had Burgers vectors of 1/3<11•0>-type. In the electron microscope, beneath the resolution of X-ray topography, short lengths of these dislocations were shown to consist of pairs of

1/3<10•0> Shockley partials which spanned narrow ribbons of stacking fault. The unusual example of a 1/3<11•0> dislocation in a Lely platelet, which visibly separated into its partials in an X-ray topograph, was presented.

Partial Dislocations in the X-ray Topography of As-Grown Hexagonal Silicon Carbide Crystals. W.M.Vetter, M.Dudley: Materials Science and Engineering B, 2001, 87[2], 173-7