Monocrystalline samples of 4H- and 6H-type material were deformed in compression at 1300C. By using 2-beam bright-field and weak-beam dark-field transmission electron microscopic techniques, the stacking-fault energies of these polytypes were estimated to be 14.7mJ/m2 (4H) and 2.9mJ/m2 (6H). These experimental values were compared with the predictions of a generalized axial next-nearest neighbour Ising spin model. It was found that the theoretical models predicted a lower stacking fault energy for 6H-type material. The predicted energies were within 5% (6H) and 40% (4H) of the experimental values.

Stacking Fault Energy of 6H-SiC and 4H-SiC Single Crystals M.H.Hong, A.V.Samant, P.Pirouz: Materials Science Forum, 2000, 338-342, 513-6