Ferromagnetic Co/Ni/Fe and Co/Fe multilayer films prepared by a three-filtered-MEVVA-ion-source-deposition system

Abstract This paper describes the preparation of ferromagnetic [Co(136 A)/Ni(25 A)/Fe(48 A)] 16 and [Co(136 A)/Fe(48 A)] 16 multilayer films with high magnetic moments by using a three-source magnetically filtered metal vapor vacuum arc deposition system. The variation of microstructure and magnetic properties of the films during a vacuum annealing process were monitored by Rutherford backscattering spectroscopy, X-ray diffraction and vibrating sample magnetometer experiments. It was found that both the saturation magnetization ( σ s ) and coercivity ( H c ) of these multilayer films were enhanced gradually by the interdiffusion and alloying effect within the multilayers of these films caused by vacuum annealing. The H c of the Co/Ni/Fe film was found to be always lower than that of the Co/Fe film under the same thermal annealing conditions, which implied that the thin nickel interlayers played a magnetically softening role in the multilayer system. The σ s value of the Co/Fe film was a little higher than that of the Co/Ni/Fe film, and the σ s values of these two films gradually became close to each other after annealing.