Magnetic Properties of Polycrystalline and Amorphous Filmsof Cobalt and Nickel Ferrite
Magnetic properties of polycrystalline and amorphous films of cobalt and nickel ferrite obtained by solid-phase synthesis are studied. Polycrystalline films of nickel ferrite are shown to be characterized by significant coercive fields at room temperature in the direction normal to the substrate plane. Compressive stresses that arise in the films during solid-phase oxidation and synthesis are assumed to contribute to the enhancement of the coercive fields. In polycrystalline films, a magnetic anisotropy of the “easy plane” type, characteristic of two-dimensional layers, is found. X-ray аmorphous films have only paramagnetic properties.