Defects present in (0 0 0 1) textured polycrystalline AlN grown by the sublimation-recombination method were analyzed using transmission electron microscopy (TEM) methods. Grains in the polycrystalline boule had either a smooth or a rough surface. The rough surface grains had mainly edge dislocations, whereas the smooth surface grains had some sub-grain boundaries and were mostly free of dislocations. Dislocations at the grain boundaries were pinned and could not be annihilated. (C) 2010 Elsevier B.V. All rights reserved.