Preparation of epitaxial Fe_3−xO₄ films by dipping-pyrolysis process using CO−CO₂ gas mixtures

Epitaxially grown Fe_3−xO₄ films were prepared on MgO(001) substrates by dipping-pyrolysis process using CO–CO₂ gas mixtures. The structure and in-plane alignment of these films were examined by x-ray diffraction θ-2θ scans, β scans (pole figures), and asymmetric ω-2θ scans (reciprocal-space maps). The films heattreated at 500 °C and higher in an atmosphere with pCO/pCO₂ = 10⁻⁴ had a spinel-type structure and were in an epitaxial (cube on cube) relationship with the substrates.