Formation of a highly oriented FeO thin film by phase transition of Fe3O4 and Fe nanocrystallines

A highly oriented FeO thin film was formed from a Fe3O4 thin film containin g Fe nanocrystallines by post-annealing at 600 degrees C. Fe3O4 thin films were grown on Si(100) substrates by ion beam sputter deposition under oxyge n ambient. The stoichiometry of the iron oxide thin film could be precisely controlled by in situ X-ray photoelectron spectroscopy (XPS). X-ray diffra ction (XRD) pattern of the Fe3O4 thin film grown at substrate temperature o f 300 degrees C showed a mixed phase of Fe3O4 and Fe nanocrystallines with a preferred orientation (110). However, the mixed phase was converted to a highly oriented FeO(200) phase by post-annealing at 600 degrees C. This cou ld be inverted as a result of Ostwald ripening of the Fe3O4 and Fe nanocrys tallines. (C) 2000 Published by Elsevier Science S.A. All rights reserved.