We investigated the effects of low-temperature deposited thin InN buffer layer on the material characteristics of the InN epitaxial films grown on a thick GaN/sapphire template by using metalorganic chemical vapor deposition. The InN buffer layer was grown at a fixed temperature of 400 degrees C with different deposition time. Compared with the InN film without the buffer layer, those with the buffer layer showed a better surface morphology, an increased X-ray diffraction intensity, a decreased background carrier concentration, and an improved photoluminescence characteristics. (c) 2006 Elsevier B.V. All rights reserved.