• Journal of the Korean Magnetics Society
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• v.5 no.6
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• pp.921-927
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• 1995

The micro particle,s shapes of the magnetic films obtained by electrode position of Iron ions and Cobalt-Iron mixed ions in aluminum anodic oxidized films are dependent on the size of particle diameter. When the diameter of deposited particles is larger than $300\AA$, the film plane anisotropy caused by bottom extremity increases, and the crystalization orientation of FeC deposited unusually in the part of the bottom extremities affects on the coercive force Hc and the magnetic anisotropy energy Ku. It was confirmed that the shape anisotropy of particle affects on the both Hc and Ku because the FeC did not deposit in the Iron deposited samples entirely, but in the Cobalt-Iron alloy deposited samples, the effects by the very strong crystalization orientation of the FeC is larger than that of the shape anisotropy. From these results, the Cobalt-Iron alloyed films could switchover the film plane magnetic anisotropy to the perpendicular magnetic anisotropy energy by using the constrainting method of FeC deposition with Cu deposition instead of Cobalt-Iron alloy in the bottom extremities.

• Journal of the Korean Magnetics Society
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• v.1 no.1
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• pp.30-36
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• 1991

A measurement system for magnetic anisotropy was built. The torque acting on the disc or sperical samples placed in uniform magnetic field was detected with a capacitive transducer which is connected with a transformer ratio-arm bridge. The output of the bridge was amplified with a lock-in amplifier. The cubic anisotropy constant for (100) of 3% Si-Fe was $3.3{\times}10^{4}\;J/m^{3}$. The calibration for the system was carried out with the shape anisotropy of a thin Ni wire.

• Journal of the Korean Magnetics Society
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• v.7 no.4
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• pp.186-190
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• 1997

We measured an anisotropy inhomogeniety and dispersion of rf sputterd permalloy thin films by TBP(Transverse Biased Permeability) measurement method. Angular distribution function had a shape similar to the Lorentzian distribution, but magnitude distribution function deviates from the sysmetric Lorentzian distribution because of long tail to the region of a high Hk value. With increasing film thickness, the angular and magnitude anisotropy dispersion increased. The increase of angular dispersion was due to both the increase of grain size and local anisotropy in thicker films.

• Proceedings of the Korean Magnestics Society Conference
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• 2002.04a
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• pp.110-111
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• 2002

• Proceedings of the Korean Magnestics Society Conference
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• 2013.05a
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• pp.92-92
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• 2013

• Proceedings of the Korean Magnestics Society Conference
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• 2001.04a
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• pp.42-43
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• 2001

• Journal of the Korean Magnetics Society
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• v.20 no.2
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• pp.35-40
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• 2010

The GMR-SV (giant magnetoresistance-spin valve) device depending on the micro patterned features according to two easy directions of longitudinal and transversal axes has been studied. The GMR-SV multilayer structure was Ta(5 nm)/NiFe(8 nm)/Cu(2.3 nm)/NiFe(4 nm)/IrMn(8 nm)/Ta(2.5 nm). The applied anisotropy direction of the GMR-SV thin film was performed under the magnitude of 300 Oe using by permanent magnet during the deposition. The size of micro patterned device was a $1\;{\times}\;18\;{\mu}m^2$ after the photo lithography process. In the aspects of the shape magnetic anisotropy effect, there are two conditions of fabrication for GMR-SV device. Firstly, the direction of sensing current was perpendicular to the magnetic easy axis of the pinned NiFe/IrMn bilayer with the transversal direction of device. Secondly, the direction of shape magnetic anisotropy was same to the magnetic easy axis of the free NiFe layer with the longitudinal direction of device.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.2
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• pp.1-6
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• 2007

This study investigated the magnetic properties of $Ni_{80}Fe_{20}/SiO_2$ laminates with shape-induced magnetic anisotropy. The multilayer films were deposited on Si or upilex substrates, from separate $Ni_{80}Fe_{20}$ and $SiO_2$ (at %) alloy targets using a rf diode sputtering system. $Ni_{80}Fe_{20}/SiO_2$ laminates with a various number of bilayers (N) were prepared. The laminates with ellipse array patterns were prepared using photolithographic technique. The magnetic properties were measured at room temperature using a B-H hysteresisgraph and a high frequency permeameter. The several steps during domain wall reversal were observed in multilayer films, attributing to inter-magnetic layer coupling. Intrinsic uniaxial anisotropy field increases with N. The experimental values of the total anisotropy field are found to be in good agreement with the calculated values. This study utilized the shape anisotropy of the laminated film objects with small ellipse array patterns to induce a larger uniaxial anisotropy so as to maximize their operating frequency.

• Journal of Magnetics
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• v.14 no.1
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• pp.18-22
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• 2009

The shape anisotropy effect of a giant magnetoresistance-spin valves (GMR-SV) device with a glass/NiO/NiFe/CoFe/Cu/CoFe/NiFe layered structure for use in the detection of magnetic property of molecules within a cell was investigated. The patterned device was given uniaxial anisotropy during the sputtering deposition and vacuum post-annealing, which was performed at $200^{\circ}C$ under a 300 Oe magnetic field. The pattern size of the device, which was prepared through the photolithography process, was $2{\times}15\;{\mu}m^2$. The experimental results confirmed that the best design for a GMR-SV device to be used as a biosensor is to have both the axis sensing current and the easy axis of the pinned NiO/NiFe/CoFe triple layer oriented in the direction of the device's width, while the easy axis of the free CoFe/NiFe bilayer should be pointed along the long axis of the device.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.2
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• pp.248-258
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• 1992

Three-dimensional rigid-plastic finite element formulation based on the membrane theory was described and a computer program for large deformation analysis was developed. In the formulation, normal and planar anisotropy of sheet material and rotation of the principal axes of anisotropy was taken into consideration. Sheet metal was assumed to be rigid-plastic material obeying Hill's quadratic yield criterion and its associated flow rule. Deep drawing process, as a preliminary test, for normal anisotropic material was analyzed in order to examine the validity of developed finite element program. The results were consistent with the existing finite element solutions or experimental data. The present study was mainly concerned with the influence of planar anisotropy on deformation behaviour. Finite element analysis and experiment were carried out for the whole process of deep drawing of planar anisotropic material. The computational and experimental results on the shape of ear, strain distribution and punch load were in good agreement.