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High saturation magnetization FeCo(Fe65 Co35)/Co films with 4πM8 about 24 kG were prepared by facing targets sputtering (FTS). A well-defined in-plane uniaxial anisotropy and excellent soft magnetic properties were obtained with a hard axis coercivity of Hch = 3 Oe by inserting a thin Co underlayer. The X-ray diffractometry (XRD) results indicate that the Co underlayer changed the main diffraction line from (200) in the FeCo single layer to (110) in the FeCo/Co films. The Co underlayer significantly reduced the average grain size from ∼74 nm for FeCo single layer to ∼8.2 nm for FeCo/Co films. A smoother surface and a narrower grain size distribution were observed in FeCo/Co films. [ABSTRACT FROM AUTHOR]

5 × 25 mm FeCoAlO gradient composition thin film was prepared with composite target by using RF magnetron sputtering. The Al-O composition gradient along the length direction of the film was introduced by Al2O3 chips asymmetrically arrayed on a Fe70Co30 target disk. The film was divided into five equal segments. All samples showed a low coercive force Hc of 4 - 8 Oe. The saturation magnetization 4πMs increased continuously from 17.3 kGs for sample 1 (has more Al-O content) to 19.7 kGs for sample 5 and it was consistent with the increasing of Fe-Co composition. Meanwhile, these samples showed different anisotropy behaviors relating with Al-O composition. The sample 1 exhibited the same magnetization curve along the directions of G| and G⊥ (G| and G⊥ are parallel and perpendicular to the direction of the Al-O composition gradient, respectively). In both of G| & G⊥ directions, the sample 1 showed a resonance frequency (fr) of around 2.6 - 3.0 GHz, while, in G| direction, it showed a high value of real permeability μ′. The sample 5 exhibited a distinct in-plane uniaxial anisotropy and a good high-frequency response of 3.0 GHz resonance frequency. So these films having gradient composition exhibit are suggested for the use in integrated magnetic devices working in the GHz frequency range. [ABSTRACT FROM AUTHOR]