An investigation was made of the propagation of threading dislocations in layers which were grown via facet-controlled epitaxial lateral overgrowth. Mixed-type dislocations were bent towards the mask areas, and terminated at voids on the SiO2 masks. Pure edge dislocations were bent in the direction of the mask stripe. No dislocations which originated from the GaN/sapphire interface propagated to the surface. As a result, a large reduction in dislocation density was achieved.

Transmission Electron Microscopy Investigation of Dislocations in GaN Layer Grown by Facet-Controlled Epitaxial Lateral Overgrowth. Y.Honda, Y.Iyechika, T.Maeda, H.Miyake, K.Hiramatsu: Japanese Journal of Applied Physics - 2, 2001, 40[4A], L309-12