Several non-polar a-plane GaN films were grown by hydride vapour phase epitaxy on different designed metal organic chemical deposition GaN templates, which exhibited various ridge-like sidewall facets surface morphologies. The templates induced a lateral growth in the early stages of hydride vapor phase epitaxial growth, and resulted in a kind of maskless epitaxial lateral overgrowth process. It was found that the dislocation reduced differently along [10•0] and [1¯1•0] directions in these hydride vapor phase epitaxial a-plane GaN layers. In the [00•1] direction, the dislocation reduction resulted from the optimal surface roughness value of the template. In the [1¯1•0] direction, the inclined facet might be a main factor for the dislocation reduction in hydride vapor phase epitaxial GaN films. The maskless epitaxial lateral overgrowth process had a significant influence on decreasing the dislocation density.

Anisotropic Defect Reduction in Non-Polar a-Plane GaN Grown by Hydride Vapor Phase Epitaxy on Maskless Patterned Templates. L.Zhao, T.Yu, J.Wu, T.Dai, Z.Yang, G.Zhang: Applied Surface Science, 2010, 256[7], 2236-40