GHz帯に共鳴周波数を有するFeCoB/NiFe/Si薄膜の透磁率特性 High Frequency Characteristics of FeCoB/NiFe/Si Thin Films with Resonance Frequency in the GHz Range
Recently the development of the magnetic devices has been expected in the high frequency applications. The soft magnetic films with large saturation magnetization and high anisotropy field <I>H<SUB>k</SUB></I> have been required. In this study, FeCoB/NiFe/Si thin films deposited by Facing Targets Sputtering (FTS) system have saturation magnetization of 2 T and <I>H<SUB>k</SUB></I> of 20 kA/m, and exhibited high ferromagnetic resonance (FMR) frequency of 6.0-7.0 GHz in permeability characteristics. For improvement of high frequency permeability characteristics, we reduced the thickness of FeCoB soft magnetic layer. The results showed that damping constant was reduced and exhibited smaller loss capability. When changing of the FeCoB thickness, we investigated the change of anisotropy field <I>H<SUB>k</SUB></I> and FeCoB(110) lattice spacing in the perpendicular direction, which indicated that there was correlation between each other. From this relationship, we examined the origin of anisotropy field <I>H<SUB>k</SUB></I>.
粉体および粉末冶金 55(2), 127-131, 2008-02-15
Japan Society of Powder and Powder Metallurgy