A method for determining the magnitude and sign of Burgers vectors of super-screw dislocations in SiC single crystals was developed. The investigated super-screw dislocations included both elementary screw dislocations and micropipes. Quantitative investigations showed that, in high-quality commercial 6H-SiC wafers, most micropipes were 4c or larger, some of 3c–7c dislocations were closed-core, and none of 2c dislocations were open-core. The magnitude of the Burgers vector was statistically proportional to the diameters of micropipes, which follows Frank's prediction. The surface energy of the micropipes in 6H-SiC was estimated to be 2.0J/m2.

A Method to Determine Superscrew Dislocation Structure in Silicon Carbide. X.Ma: Materials Science and Engineering B, 2006, 129[1-3], 216-21