Effect of the magnetization process on low-field microwave absorption by FeBN magnetic thin film

摘要

The magnetization process of a typical soft magnetic film was examined using ferromagnetic resonance (FMR) measurements on 9.84 GHz. A 500-nm-thick Fe_(85.9)B_(2.6)N_(11.5) film with in-plane uniaxial magnetic anisotropy was deposited by RF sputtering. The saturation magnetization and coercivity of the FeBN magnetic film were 17.3 kG and 2.4 Oe, respectively, at the hard direction. The microwave absorption signals showed two different absorption peaks: small signals at a near zero dc field and at a high dc field. The resonance magnetic fields for the major and minor peaks were observed at 532 and 604 Oe, respectively. The g-factor obtained was 2.15. The uniaxial magnetic anisotropy field was approximately 14 Oe by vibrating sample magnetometer, which coincided with that of the FMR results. The absorption at a low-field revealed different characteristics from those of conventional FMR absorption. The magnetic anisotropy field obtained by low-field microwave absorption was approximately 13.5 Oe, which is comparable to that of the FMR and VSM results.