A method to determine the magnitude and the sign of Burgers vectors of super-screw dislocations in silicon carbide single crystal was developed. The investigated super-screw dislocations include 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 followed 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