Influence of modulated structure on magnetic properties of NdFeB/Co multilayer thin films

Abstract

The NdFeB/Co multilayer films were prepared by magnetron sputtering. After that, the samples were annealed at 600 °C for 20 min. The surface morphology, phase structures and magnetic properties of Mo (50 nm)/[NdFeB (100 nm)/Co(y)]×10/Mo (50 nm) thin films were researched by AFM, XRD and VSM, respectively. The results show that the films show stronger perpendicular magnetic anisotropy. When the thickness of Co layers is 10 nm, the coercivity H_c⊥ is the maximum, 295 kA/m. However, for y=10-20, the reduced remanence M/M_s of films has increased. When the thickness of Co layers is 20-30 nm, the NdFeB/Co multilayer films obtained more superior magnetic properties with M/M_s =0.95.

Keywords

NdFeB/Co film / modulated structure / perpendicular magnetic anisotropy / coercivity / reduced remanence

References

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