The GaN layers were grown by compound-source molecular beam epitaxy (CS-MBE) on (1 1 1) aluminum (Al) substrates with and without mitriclation. The melting point of Al substrates limits the growth temperature. The layers were grown at 650 degrees C. Reflection high-energy electron diffraction (RHEED) patterns of the layers indicate that the mitriclation is effective for GaN growth by CS-MBE on aluminum substrates. Photoluminescence was observed from the layer grown on the Al substrate with nitridation at RT. (C) 2008 Elsevier B.V. All rights reserved.