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Co-ferrite thin film with spinel structure is attractive for spintronics and multifunctional devices. So far, single-crystal substrates are necessary to introduce perpendicular magnetic anisotropy in co-ferrite films. In this paper, a unique process has been developed to deposit co-ferrite thin films onto thermally oxidized silicon wafer with perpendicular magnetic anisotropy. We have successfully prepared co-ferrite films with (00l) orientation. Those films show perpendicular coercivities as large as 12.8 kOe. X-ray diffractometry results revealed that compressive strain, which is introduced by the postannealing process rather than deposition process, is as large as 1.3% in films with (00l) orientation. The large coercivity and perpendicular magnetic anisotropy can be quantitatively explained by the magnetoelastic effect. This silicon-compatible fabrication process is useful to further extending the applications of co-ferrite films. [ABSTRACT FROM AUTHOR]

Magnetic force microscope (MFM) probes are fabricated by coating magnetically soft FeCo films in a facing targets sputtering (FTS) system. Compared with DC magnetron sputtering, probes coated by FTS show smaller tip radius. Lateral resolution about 12 nm has been achieved by the probes. Simulation results show that a magnetic vortex is formed at the probe apex. The resulting effective magnetic moment of the probes will be minimized by the formation of vortex. We show that these probes have higher lateral resolution than the standard, commercially available MFM probes. [ABSTRACT FROM PUBLISHER]

A method of introducing pinning sites in TbFeCo film by the using of focused ion beam was presented. The formed bulges in the film surface by discontinuous scan of light-dose focused ion beam have been proved to enhance the film's coercivity effectively. Coercivity increases almost linearly with the bulge density, giving the evidence of pinning effect contributed from those bulges predicted by domain wall pinning mechanism. Compared with the traditional way of etching the film for adjusting the coercivity, the method presented here shows superiority on reducing magnetic damage to film caused by the focused ion beam irradiation. [ABSTRACT FROM PUBLISHER]

Substituted strontium ferrite (\SrFe12-x{(\Cr0.5\Al0.5)}_x\O19) thin films were formed along the surface of multiwalled carbon nanotubes (MWCNTs). Mössbauer spectroscopy indicates that the substituted cations preferentially occupy the 12k sites. X-ray diffraction (XRD), transmission electron microscope (TEM), field emission scanning electron microscope (FE-SEM), vibrating sample magnetometer (VSM), and vector network analyzer were used to analyze the structure, static, and high-frequency magnetic properties of the prepared samples. It was found that with an increase in substitution content, the saturation of magnetization decreases while the coercivity increases. The CNTs could enhance the real and imaginary parts of permittivity of ferrites. With an increase in volume percentage of MWCNTs, the reflection loss values were increased. [ABSTRACT FROM AUTHOR]

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]