Properties of aluminum nitride layers grown by hydride vapor phase epitaxy (HVPE) on 2 in sapphire and silicon carbide (SiC) substrates are described. Thickness of grown AlN layers ranged from 1 to 20 mu m for the material grown on sapphire and from 5 to 75 mu m for the material grown on SiC. The layers were free of cracks. Surface morphology, crystal quality, electrical resistivity, and optical transparency of grown AlN layers were studied. 2 in free-standing AlN wafers were fabricated. (c) 2005 Published by Elsevier B.V.