Large-angle convergent-beam electron diffraction analysis was successfully performed on pairs of partial dislocations which were so close that their effect upon Bragg lines overlapped. These pairs, dragging 3C layers, were nucleated by mechanical deformation of 4H-SiC. Splitting of Bragg lines upon crossing a dislocation pair could be interpreted as resulting from a single dislocation having a Burgers vector, b, equal to the sum of those of the 2 partial dislocations. Splitting rules using phase-shifted reflections (g▪b ≠ n, with n  Z) were also given depending on the phase shift produced by 3C lamellae. These results give a b-direction in agreement with weak-beam dark-field studies and suggested that Si core dislocations have highest mobilities for low-temperature (<700C) plastic deformation.

LACBED Study of Extended Defects in 4H-SiC. M.Texier, G.Regula, M.Lancin, B.Pichaud: Philosophical Magazine Letters, 2006, 86[9], 529-37