Epitaxial growth of spinel cobalt ferrite films on MgAl2O4 substrates by direct liquid injection chemical vapor deposition

• Growth of cobalt ferrite via direct liquid injection chemical vapor deposition.
• Narrow growth window for smooth and epitaxial films, with bulk-like properties.
• Ordering of Fe3+ and Co2+ on the B-site extracted from Raman studies.
• Deposition method allows epitaxial growth on a variety of substrates.

The direct liquid injection chemical vapor deposition (DLI-CVD) technique has been used for the growth of cobalt ferrite (CFO) films on (100)-oriented MgAl2O4 (MAO) substrates. Smooth and highly epitaxial cobalt ferrite thin films, with the epitaxial relationship MAO(100)[001]∥CFO(100)[001]MAO(100)[001]∥CFO(100)[001], are obtained under optimized deposition conditions. The films exhibit bulk-like structural and magnetic properties with an out-of-plane lattice constant of 8.370 Å and a saturation magnetization of 420 kA/m at room temperature. The Raman spectra of films on MgAl2O4 support the fact that the Fe3+- and the Co2+-ions are distributed in an ordered fashion on the B-site of the inverse spinel structure. The DLI-CVD technique has been extended for the growth of smooth and highly oriented cobalt ferrite thin films on a variety of other substrates, including MgO, and piezoelectric lead magnesium niobate–lead titanate and lead zinc niobate–lead titanate substrates.