We report a novel growth technique of GaN films on Si substrates using a metalorganic chemical vapor deposition. First, Ga droplets are deposited on a Si substrate by feeding trimethylgallium. And then the substrate is heated at 1080 degrees C, resulting in the formation of recesses on its surface by meltback etching. Finally, a GaN film is grown on the Ga-induced meltback-etched surface using a high-temperature-grown AlN intermediate layer. After the growth of the GaN film, 0.5-1-mu m-diameter pits were observed on the GaN surface. A cathodoluminescence image reveals that low-threading-dislocation-density regions were successfully grown around the pits. (C) 2010 Elsevier B.V. All rights reserved.