Study on the Preparation and Room-Temperature Ferromagnetic of Binary Manganese-Vanadium Oxide Thin Films

In this work, magnetic vanadium oxide(VO_x) thin films were prepared on sapphire substrates by RF magnetron sputtering. The effects of codeposition of Mn on the surface morphology and ferromagnetism of VO_x were investigated. The results of structure and morphology characterization show that the VO_x film prepared by us is a kind of pure vanadium oxide film with a stoichiometric ratio between V₂O₃ and VO₂. The introduction of Mn element causes slight distortion of VO_xlattice, and the morphology of VO_x evolves from a nano-rod structure to a spherical structure. The results of magnetic properties show that VO_x films exhibited room-temperature ferromagnetic properties. With the ratio of Mn to V being 1:1, the saturation magnetic moment of the film first increases and then decreases. When the Mn content is 30%, the surface morphology is the most regular, and the maximum saturation magnetic moment is 345 emu/cm³.