Open-ended stacking-fault tetrahedra in X-ray topographs of cubic silicon carbide

Trihedral configurations of stacking faults have been observed in X-ray topographs of a 3C-SiC platelet. The trihedra were formed of stacking faults lying on three {111} planes, and 1/6(110) stair-rod dislocations formed their edges. The open side of the trihedra extended to the crystal's surface, giving these defects the same form as the open-ended stacking-fault tetrahedra that are sometimes observed in the transmission electron microscopy of misfit-strained epitaxial layers. However, these trihedra are much larger, 40-200 μm across, and are a growth defect, originating from a mechanism other than the condensation of vacancies or the release of misfit strain.