Chemical solution deposition derived buffer layers for MOCVD-grown GaN films

A polymeric Ga-containing liquid precursor was used for the first time to p repare a buffer layer for the growth of GaN by metalorganic chemical vapor deposition. The buffer layer was prepared by chemical solution deposition ( CSD), i.e. spincoating the precursor on a sapphire substrate followed by py rolysis in ammonia. The GaN films were characterized by optical and electro n microscopy, XRD rocking curves, photoluminescence and Hall measurements. The CSD-buffered GaN films showed a significantly better crystal quality th an unbuffered films and came close to the quality of conventionally buffere d ones. (C) 2001 Elsevier Science B.V. All rights reserved.