The crystal quality of a-plane GaN films was improved by using epitaxial lateral

overgrowth on a nanorod GaN template. The investigation of X-ray diffraction

showed that the strain in a-plane GaN grown on r-plane sapphire could be

mitigated. The average threading dislocation density estimated by transmission

electron microscopy was reduced from 3 x 1010 to 3.5 x 108cm−2. From the

temperature-dependent photoluminescence, the quantum efficiency of the a-plane

GaN was enhanced by the nanorod epitaxial lateral overgrowth. These results

demonstrated the opportunity of achieving a-plane GaN films with low dislocation

density and high crystal quality via nanorod epitaxial lateral overgrowth. Nanorod Epitaxial Lateral Overgrowth of a-Plane GaN with Low Dislocation

Density. S.C.Ling, C.L.Chao, J.R.Chen, P.C.Liu, T.S.Ko, T.C.Lu, H.C.Kuo,

S.C.Wang, S.J.Cheng, J.D.Tsay: Applied Physics Letters, 2009, 94[25], 251912