Interface characteristics of iso-structural thin film and substrate pairs

Cubic-CeO(2) and alpha-Fe(2)O(3) thin films have been epitaxially grown on yttria-stabilized ZrO(2) and alpha-Al(2)O(3) substrates, respectively.. by oxygen plasma assisted molecular beam epitaxy. The interface structural features between the films and the substrates were characterized by Rutherford backscattering spectrometry (RBS), high resolution transmission electron microscopy (HRTEM), and X-ray diffraction (XRD). RBS channeling spectra for both CeO(2)/ZrO(2) and Fe(2)O(3)/Al(2)O(3) show interface disorder-related scattering peaks. It is believed that the observed interface disorder-related scattering peaks in the RBS spectra are due to interface misfit dislocations. Cross sectional HRTEM reveals that interfaces of both systems are similarly characterized by coherent regions that are separated by misfit dislocations periodically distributed along the interface. The experimentally observed dislocation spacings are approximately consistent with those calculated from the lattice mismatch, implying that the lattice mismatch is accommodated mainly by interface misfit dislocations. (C) 2003 Elsevier Science B.V. All rights reserved.