In this study, heavily Si-doped n-type GaN (n-GaN) epitaxial layers with and without nanorod GaN (NR GaN) template were grown by metal organic chemical vapor deposition (MOCVD) system. It was found that we could achieve high-qulaity heavily Si-doped n-GaN layers by using the NR GaN template. It was also found that we can reduce etching pits density in n-GaN (1.5E19 cm(-3)) epitaxial layer by a factor of 2.82 using the NR GaN template, as compared to the conventional sapphire substrate. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3617533] All rights reserved.