A threading dislocation (TD) in 4H-SiC, which was interpreted as a right-handed threading screw dislocation (TSD) by synchrotron monochromatic-beam X-ray topography (SMBXT) and molten KOH etching with Na2O2 additive (KN etching), was characterized by large-angle convergent-beam electron diffraction (LACBED) and weak-beam dark-field methods. It was found that this TD was a so-called c+a dislocation with Burgers vector of b=[00•1]+(1/3)[21•0], which was often misinterpreted as TSD (c-dislocation) by SMBXT and KN etching. The rotation direction of the screw component within the c+a TD determined by LACBED agreed with the SMBXT observation.

Transmission Electron Microscopy Analysis of a Threading Dislocation with c+a Burgers Vector in 4H-SiC. Y.Sugawara, M.Nakamori, Y.Z.Yao, Y.Ishikawa, K.Danno, H.Suzuki, T.Bessho, S.Yamaguchi, K.Nishikawa, Y.Ikuhara: Applied Physics Express, 2012, 5[8], 081301