HfAl(2)O(5) dielectric film with an O-gettering Ti-capping layer was treated with rapid thermal annealing process and its interfacial structure and surface morphology were reported. X-ray reflectivity measurements and X-ray photoelectron spectroscopy indicated that the interfacial layers were composed of a 0.5 nm HfAlSiO layer and a 1.5 nm Si(x)(SiO(2))(1-x) (X<1) layer for the as-deposited film. However, for the annealed film, HfAlSiO layer was not found and the 1.5 nm Si(x)(SiO(2))(1-x) transformed to a 1 nm SiO(2). Atom force microscopy showed that a Ti-capping layer did not affect surface roughness. (C) 2008 Elsevier BY. All rights reserved.