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The longitudinal CoCrPt thin films have been prepared on CrW underlayer at room temperature. The dependence of CoCrPt’s structure and magnetic properties on the Pt content was investigated. The addition of platinum element in the CoCrPt magnetic layer increases the lattice constant and longitudinal coercivity of the CoCrPt thin films. The coercivity mechanism of the CoCrPt thin film is analyzed by using the micromagnetic models, with careful discussions of the uniaxial crystalline anisotropy and the magnetostriction. It is found that the magnetostriction effects play an important role on the coercivity mechanisms when the Pt content is more than 15 at. % Pt concentrate. [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]

The soft magnetic FeCoAlO thin films with different response at high frequency were prepared by using RF magnetron sputtering. Two different configurations of the sputtering targets were used: the Al2O3 chips were placed on Fe70Co30 disk either uniformly dispersed on the sputtering area (Target-A) or dispersed on the half side of the sputtering area (Target-B). It was found that, although, the films deposited from both of Target A and B possessed good soft magnetic properties and in-plane uniaxial magnetic anisotropy, they showed different behaviors at high frequency. The films deposited by using Target-A have mean permeability of 500 and a cut-off frequency (fr) of around 780 MHz, while the films deposited by using Target-B have mean permeability of 200 and a fr of 3.4 GHz. The higher fr of the later corresponds to the higher uniaxial anisotropic field in the films deposited by using the Target-B, which due to an extra anisotropy induced by the stress resulted from gradient of the Al-O composition. By adjusting the configuration of Target-B, the permeability & fr can be tuned to satisfy the different requirements for certain industrial applications. [ABSTRACT FROM AUTHOR]