The growth characteristics and atomic structures of defects were investigated in AlN thin films which were grown by metal-organic chemical vapor deposition onto the (10•2) r-plane of α-Al2O3. The AlN films were monocrystalline, and had an epitaxial relationship, (11•0)AlN||(10•2)sapphire, with an in-plane alignment of [00•1]AlN||[¯10•1]sapphire. By using high-resolution electron microscopy and multi-slice image simulation, the predominant defects in the AlN thin films were found to be low-energy intrinsic stacking faults of type-I1 which lay in the basal plane. This fault, with a 1/6[20•3] resultant displacement vector, could be formed by removing one (00•2) plane and then shearing the remaining half-crystal by a displacement of 1/3[10•0]. The faults appeared as a single face-centered cubic stack, ABC, which was inserted into the normal, ... ABAB..., hexagonal sequence.

K.Dovidenko, S.Oktyabrsky, J.Narayan: Journal of Applied Physics, 1997, 82[9], 4296-9