Abstract
The surface morphology of RF magnetron sputtering Ta <sub>2</sub> O <sub>5</sub> films on Si substrates was studied by X-ray reflectivity measurement and atomic force microscopy. The growth exponent β was found to be 0.49±0.05 for the polycrystalline films with thickness over 10 nm. During the early stage of polycrystalline Ta <sub>2</sub> O <sub>5</sub> growth, the surface roughness change indicates the development of an island nucleation process and an island coalescence morphology. For the amorphous thin films, the surface roughness was 0.32±0.03 nm with β<0.05, which is much smoother than that of the polycrystalline films. It might indicate that mounds or facet grow on the surfaces of polycrystalline thin films. © 2002 Elsevier Science B.V. All rights reserved.