Defect states in the form of band edge electron and hole traps in HfO(2) nano-crystalline films are qualitatively different in two different length scale regimes. For grain sizes >3-4 nm, they are discrete band edge states associated with O-atom vacancies pinned and clustered at grain boundaries, whereas in as-deposited films, and films with a physical thickness of similar to 2 nm, they are band-tail defects with a density reduced by more than an order of magnitude. Defect states in non-crystalline high Si(3)N(4) content Hf Si oxynitride alloys are qualitatively different than those in the either regime of nano-crystallinity, but instead are similar to those in SiO(2), with densities <10(11) cm(-2) contrasted with defects densities in excess of 10(11) cm(-2) in films with nanograins similar to 2 nm, and extending to >10(12) cm(-2) in films with nano-grains >3-4 nm. (C) 2008 Published by Elsevier B.V.