Dislocations in Si were nucleated under high stresses as perfect ones in the shuffle set. It was shown that the same nucleation mechanism operates in hexagonal 4H-polytype SiC but, in contrast to Si, perfect-shuffle configurations were unstable and transform by cross-slip into glide set dislocations.

On the Core Structures of Dislocations in Semiconductors. J.Rabier, J.L.Demenet, M.F.Denanot, X.Milhet: Materials Science and Engineering A, 2005, 400-401, 97-100