Magnetism and structure of ZnxFe3-xO4 films processed via spin-spray deposition

Zn-ferrite films, ZnxFe3-xO4 where the Zn:Fe ratio ranges from 0.36 to 0.76, were grown on glass substrates using a spin spray technique. Films are shown using scanning electron microscopy and atomic force microscopy to be dense and granular with an average grain size similar to0.3 mum. X-ray diffraction indicates that the films are a Fd3m symmetry consistent with a pure spinel ferrite phase. The films' coercive fields have a strong positive correlation with the film roughness indicating the dominance of a physical domain wall pinning mechanism. The films are smooth and magnetically soft near the ZnFe2O4 stoichiometry. All films, including those near the ZnFe2O4 stoichiometry, display ferrimagnetic behavior with compensation temperatures well above the bulk Neel temperature of 9.5 K; this is attributed to the cation disorder measured in the Zn cation distribution. (C) 2002 American Institute of Physics.