Modification of structure and magnetic anisotropy of epitaxial CoFe2O4 films by hydrogen reduction
- 16 March 2015
- journal article
- conference paper
- Published by AIP Publishing in Applied Physics Letters
- Vol. 106 (11) , 111907
Abstract
Heteroepitaxial CoFe2O4 (CFO) thin films with different thicknesses were deposited on MgO (001) substrates. The as-deposited CFO films show a clear switching of magnetic anisotropy with increasing film thickness. The thinner films ([001] = −188 × 10−6. Metallic CoFe2 films were obtained by annealing the as-deposited CFO films in forming gas (Ar 93% + H2 7%) at 450 °C. XRD shows that CoFe2 films are textured out-of-plane and aligned in-plane, owing to lattice matching between CoFe2 and MgO substrate. TEM results indicate that as-deposited films are continuous while the annealed films exhibit a nanopore mushroom structure. The magnetic anisotropy of CoFe2 films is dominated by the shape effect. The results demonstrate that hydrogen reduction can be effectively used to modify microstructures and physical properties of complex metal oxide materials.Keywords
Funding Information
- U.S. Department of War
This publication has 18 references indexed in Scilit:
- Crossover of uniaxial magnetic anisotropy direction mediated by interfacial strain of CoFe2O4 filmsJournal of Magnetism and Magnetic Materials, 2014
- Strain relaxation and enhanced perpendicular magnetic anisotropy in BiFeO3:CoFe2O4 vertically aligned nanocomposite thin filmsApplied Physics Letters, 2014
- Reduction of graphene oxide films on Al foil for hybrid transparent conductive film applicationsCarbon, 2013
- Engineered Magnetic Shape Anisotropy in BiFeO3–CoFe2O4 Self-Assembled Thin FilmsACS Nano, 2013
- Role of crystal orientation on the magnetic properties of CoFe2O4 thin films grown on Si (100) and Al2O3 (0001) substrates using pulsed laser depositionPhysica B: Condensed Matter, 2011
- Reduction of FeO/Pt(111) thin films by exposure to atomic hydrogenSurface Science, 2010
- Stress-induced magnetic anisotropy of CoFe2O4 thin films using pulsed laser depositionJournal of Magnetism and Magnetic Materials, 2007
- Spin valves using insulating cobalt ferrite exchange-spring pinning layersApplied Physics Letters, 2002
- The reduction of copper oxide thin films with hydrogen plasma generated by an atmospheric-pressure glow dischargeJournal of Physics D: Applied Physics, 1996
- Epitaxial P-Type Germanium and Silicon Films by the Hydrogen Reduction of GeBr[sub 4], SiBr[sub 4], and BBr[sub 3]Journal of the Electrochemical Society, 1963