Fecosib Amorphous Magneto-elastic Film Material And Applied Research

Extensive studies have been conducted on the FeCoSiB thin film for its perfect magnetoelastic property. In this thesis, the stress impedance effects of the FeCoSiB thin film have been studied and the tunable planar thin film inductor based on the magnetoelastic property of FeCoSiB thin film has been prepared. The high frequency permeability and the impedance of the FeCoSiB thin film have been deduced theoretically based on the Landau-Lifshitz-Gilbert equation and the Maxwell equations. The influences of the parameters such as the depth, the anisotropy field, the internal stress and the saturation magnetization of the thin film on the impedance of the FeCoSiB thin film have been discussed. The results show that stress impedance effect can be obtained obviously when the depth of the thin film is bigger than the skin depth of the thin film. And the stress impedance effect can be increased when the direction of magnetic anisotropy filed or that of the internal tensile stress is perpendicular to that of the applied stress of the thin film with high saturation magnetization. The FeCoSiB thin film and FeCoSiB/Cu/FeCoSiB multi-layers have been prepared by DC magnetron sputtering on glass substrate, and annealed in a static magnetic field subsequently. The influences of the sputtering conditions on the stress impedance effect have been studied. The experimental results show that good stress impedance effect of the FeCoSiB thin film with the thickness of 2μm has be obtained when the Ar pressure is 2Pa and the thin film is annealed in 300 Oe magnetic filed at 300℃for 60 minutes. Compared with the FeCoSiB thin film, the stress impedance effect of the FeCoSiB/Cu/FeCoSiB mutilayers is bigger than that of the FeCoSiB thin film. The tunable planar thin film inductor with the structure of Cu/PI/FeCoSiB/TbFe2/Substrate has been fabricated. The inductances of the inductor...