Abstract
Fe-doped NiO polycrystalline and {111} epitaxial films were grown by solid-source metalorganic chemical vapor deposition. The exchange field for NiFe on the polycrystalline Fe-doped NiO films increased with Fe content up to 18 at. % Fe, and then decreased with further increases in Fe content; the coercivity, blocking temperature, and grain size monotonically decreased with increasing Fe content. Similar results were observed in {111} films. The increase of the exchange field and the reduction of the blocking temperature are attributed to dissolved Fe atoms in the NiO. Low exchange coupling between NiFe and α- Fe 2 O 3 may be responsible for the decrease of the exchange field in highly Fe-doped NiO films. Furthermore, 18% Fe-doped NiO showed an enhancement of exchange fields at thicknesses between 450 and 950 Å, and a considerable large training effect was observed. © 1997 American Institute of Physics.