Polymetallic citric complexes as precursors for spray-pyrolysis deposition of thin ferrite films

Thin films of ferrites of the type M^IIFe₂O₄ (M = Cu, Mg, Zn) are prepared by spray-pyrolysis using ethylene glycol solutions of mixed-metal citric complexes of the respective metals at substrate temperature between 350 °C and 450 °C and post-deposition annealing at 480-750 °C in air. Phase composition, crystal structure, morphology and adhesion of the obtained films (40-400 nm in thickness) are studied by X-ray diffraction, SEM, energy dispersive X-ray microanalysis and AFM. Single phase dense uniform films with grains from 30-100 nm (M = Cu, Mg) to 0.15-2 μm (M = Zn) are obtained.