The tilt and twist of GaN prepared by facet-controlled epitaxial lateral overgrowth were evaluated by the X-ray rocking curve measurement of symmetrical and asymmetrical reflections. Compared to the underlying GaN, the tilt and twist values became substantially smaller at 130 and 250arcsec, respectively, which were consistent with published results of transmission electron microscopy and cathode luminescence analyses. Moreover, facet-controlled epitaxial lateral overgrown GaN was almost free of small angle tilt boundaries in contrast to GaN prepared by simple epitaxial lateral overgrowth.

X-Ray Analysis of Twist and Tilt of GaN Prepared by Facet-Controlled Epitaxial Lateral Overgrowth (FACELO). Y.Iyechika, M.Shimizu, T.Maeda, H.Miyake, K.Hiramatsu: Japanese Journal of Applied Physics-2, 2003, 42[7A], L732-4