Defects introduced in [11•0] N-doped 4H-SiC by surface scratching and bending at

823 or 973K were characterised by weak beam-dark field transmission electron

microscopy, high-resolution transmission electron microscopy, large-angle

convergent beam electron diffraction, image analysis and dislocation core reconstruction. They consist of double stacking faults dragged by partial

dislocation pairs in planes in which the Si-C dumb-bells had the same orientation.

The partial dislocations forming a pair always had the same Burgers vectors. The

reconstructions prove that their core composition depends on the dislocation

character, the expansion direction and the orientation of the dumb-bells in the glide

planes. Only Si(g) were mobile, the lack of mobility of C(g) explaining why only

three kinds of half-loops expand and why one double stacking faults was always

edged by two identical partial dislocations. It was shown that the line morphology

was not a sufficient criterion to determine the core composition. Although

mechanical stresses were applied, additional thermodynamic and/or electronic

driving forces influenced the double stacking fault formation.

Defects Created in n-Doped 4H-SiC in the Brittle Regime: Stacking Fault

Multiplicity and Dislocation Cores. M.Lancin, M.Texier, G.Regula, B.Pichaud:

Philosophical Magazine, 2009, 89[15], 1251-66