Polycrystalline GaN films grown on silica substrates by metalorganic chemical vapor deposition were irradiated by a KrF excimer laser. As the laser energy density increased, it was observed that the surface became smoother and the GaN grain size became larger. Band-edge (BE) emissions were found to become stronger at higher laser energy densities whereas yellow luminescence (YL) emissions were unchanged. It was thought that the laser irradiation had a significant effect on the BE emissions which strongly depended on surface morphologies, but no effect on the YL emissions which originated from the entire GaN film due to a shallow irradiation depth. (C) 2003 Elsevier Science B.V. All rights reserved.