Highly crystalline nickel ferrite films with different chemical compositions were processed via the spin-spraying method and their morphological, structural and magnetic properties were subsequently investigated. Regardless of the chemical composition, films with variable thicknesses are constructed by 200–400 nm spherical grains grown in the direction normal to the substrate surface. Magnetization measurements show that the spinel ferrite films present a hysteretic behaviour at room temperature with a randomly oriented in-plane easy axis and an anisotropy constant K1 ≈ −2.5 × 104 erg cm−3 Furthermore, the absence of an angular dependence of the coercivity for the in-plane measurement of magnetization coupled with the ‘M’-shaped angular dependence of the out-of-plane measurement, indicates that the anisotropy of this film is predominantly crystalline shape anisotropy.
Journal of Physics D: Applied Physics
J. Phys. D: Appl. Phys. 38 (2005) 811–815