Transmission electron microscopy was used to investigate the structure of inversion domain boundaries in α-phase (00•1) films which had been grown, via metal-organic chemical vapor deposition, onto sapphire substrates. Convergent-beam electron diffraction was used to establish the existence of inversion domains with {10•0} boundaries. The displacement fringes, which were observed in 2-beam images that were obtained from inclined inversion domain boundaries, were compared with dynamic simulations. It was shown that the results were consistent with an atomic model in which 4-fold bonding was preserved, with all bonds being of Ga-N type.

D.Cherns, W.T.Young, M.Saunders, J.W.Steeds, F.A.Ponce, S.Nakamura: Philosophical Magazine A, 1998, 77[1], 273-86