• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.451-452
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• 2006

We studied the electro-optical characteristic of vertical alignment liquid crystal display(VA-LCD) on the $SiO_x$ thin film deposited $45^{\circ}$ oblique by rf magnetic sputtering system. LC alignment characteristic showed homeotropic alignment, and pretilt angle was about $90^{\circ}$. A uniform liquid crystal alignment effect on the $SiO_x$ thin film was achieved and the electro-optical characteristic of the $SiO_x$ thin film deposited $45^{\circ}$ oblique by rf magnetic sputtering system was excellent.

• Proceedings of the Korean Magnestics Society Conference
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• 2003.06a
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• pp.216-217
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• 2003

• Journal of the Korean Magnetics Society
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• v.3 no.4
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• pp.320-324
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• 1993

The effect of sputtering conditions on magnetic properties of CoCrMo/Cr magnetic thin film was investigated. Substrate temperature were controlled from R. T to $250^{\circ}C$. The thickness changes of Cr underlayer and CoCrMo magnetic layer were in the range of $1000-2500\AA$ and $300-800\AA$, respectively. Grain size was found to be decreased with increasing magnetic layer thickness(from $500\AA$ to $800\AA$). CoCrMo magnetic layer microstructure showed relatively small dependence on Cr underlayer thickness, substrate temperature. Coercivity increased with increasing Cr underlayer, magnetic layer thickness and substrate temperature. CoCrMo/Cr thin film showed a coercivity of 880 Oe in $700\AA$ magnetic layer thickness and $1000\AA$ Cr underalyer thickness.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.11a
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• pp.267-270
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• 2003

We have studied the interfacial diffusion phenomena and the role of ${\alpha}-Al_2O_3$ buffer layer as a diffusion barrier in the $Ba-ferrite/SiO_2$ magnetic thin films for high-density recording media. In the interface of amorphous Ba-ferrite ($1900-{\AA}-thick)/SiO_2$ thin film during annealing, the interfacial diffusion started to occur at ${\sim}700^{\circ}C$. As the annealing temperature increased up to $800^{\circ}C$, the interfacial diffusion abruptly proceeded resulting in the high interface roughness and the deterioration of the magnetic properties. In order to control the interfacial diffusion at the high temperature, we introduced ${\alpha}-Al_2O_3$ buffer layer ($110-{\AA}-thick$) in the interface of $Ba-ferrite/SiO_2$ thin film. During the annealing of $Ba-ferrite/{\alpha}-Al_2O_3/SiO_2$ thin film even at ${\sim}800^{\circ}C$, the interface was very smooth. The smooth interface of the film was also clearly shown by the cross-sectional FESEM. The magnetic properties, such as saturation magnetization 3nd intrinsic coercivity, were also enhanced, due to the inhibition of interfacial diffusion by the ${\alpha}-Al_2O_3$ buffer layer. Our study suggests that the ${\alpha}-Al_2O_3$ buffer layer act as a useful interfacial diffusion barrier in the $Ba-ferrite/SiO_2$ thin films.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.7
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• pp.563-568
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• 2012

Indium tin oxide (ITO) films were prepared using radio frequency (RF) magnetron sputtering method, magnets were equipped near the target in the sputter to bring the plasma near the target. The effect of magnetic field that brings the plasma near the substrate was compared with that of substrate heating. The effect of substrate heating on the grain size of the ITO thin film was larger than that of the magnetic field. However, the grain size of the ITO thin film was larger when the magnetic field was applied near the substrate during the sputtering process than when the substrate was not heated and the magnetic field was not applied. If stronger magnetic field is applied near the substrate during sputtering, it can be expected that the ITO thin film with good electrical conductivity and high transparency is obtained at low substrate temperature. When magnetic field of 90 Gauss was applied near the substrate during sputtering, the mobility of the ITO thin film increased from 15.2 $cm^2/V.s$ to 23.3 $cm^2/V.s$, whereas the sheet resistivity decreased from 7.68 ${\Omega}{\cdot}cm$ to 5.11 ${\Omega}{\cdot}cm$.

• Journal of Magnetics
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• v.5 no.2
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• pp.44-49
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• 2000

Computer simulation of sensing current effects on the magnetic and magnetoresistance properties of a crossed spin-valve head is carried out. The spin-valve head has the following layer structure: Ta (8.0 nm)/NiMn (25 nm)/NiFe (2.5 nm)/Cu (3.0 nm)/NiFe (5.5 nm)/Ta (3.0 nm), and it is 1500 nm long and 600 nm wide. Even with a high pinning field of 300 Oe and a high hard-biased field of 50 Oe, the ideal crossed spin-valve structure, which is essential to the symmetry of the output signal and hence high density recording, is not realized mainly due to large interlayer magnetostatic interactions. This problem is solved by applying a suitable magnitude of sensing currents along the length direction generating magnetic fields in the width direction. The ideal spin-valve head is expected to show good symmetry of the output signal. This has not been shown explicitly in the present simulation, however, The reason for this is possibly related to the simple assumption used in this calculation that each magnetic layer consists of a single domain.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.208-211
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• 2000

We prepared Co-Cr-Ta and Co-Cr-Ta/Ti thin film for perpendicular magnetic recording media by facing targets sputtering system (FTS system). Ti underlayer effects on crystallographic and magnetic characteristics of Co-Cr-Ta perpendicular magnetic recording media have been investigated. Crystallgraphic and magnetic characteristic of prepared thin films were evaluated by x-ray diffractometry(XRD), vibrating sample magnetometer(VSM) and kerr hysteresis loop measurement. The coercivity and anisotropy field increase by introduced Ti underlayer when substrate temperature is higher than 150$^{\circ}C$. The c-axis dispersion angle and grain size of Co-Cr-Ta/Ti thin film is decrease than Co-Cr-Ta when substrate temperature is higher than 100$^{\circ}C$. Consequently, the use of a Ti underlayer highly orientated can be improved crystallographic and magnetic characteristics of Co-Cr -Ta perpendicular media layer.

• Current Applied Physics
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• v.18 no.11
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• pp.1196-1200
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• 2018

We have experimentally demonstrated circular polarization generation from linear polarized soft X-ray at synchrotron by adopting a thin magnetic film polarizer. Polarizer is composed of Co/Pt multilayer with a perpendicular magnetic anisotropy, which allows us to easily accommodate without needing any tilting angle into the measurement setup since the circular polarization is generated for the X-ray with normal incidence and transmission. Generated circular polarization is examined by observing magnetic domain features based on the X-ray magnetic circular dichroism, where~11% of circular component is estimated compared to the case of full circular polarization.

• Journal of Magnetics
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• v.11 no.3
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• pp.130-134
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• 2006

The microwave power absorption for the patterned CoNbZr magnetic film has been investigated by coplanar waveguide method. The power absorption peaks of the patterned CoNbZr film (50 ${\mu}m$ ${\times}$ 2 mm ${\times}$ 2 ${\mu}m$), were observed at around 5.7 GHz. The observed resonance peak was in good agreement with calculated ferromagnetic resonance frequency including magnetic shape anisotropy effects. Compared with the coplanar waveguide without a magnetic film, the characteristic impedance of patterned film was shown to be increased. This resulted from the large increment of inductance up to 33 % without any significant changes of the capacitance.

• Journal of the Korean Magnetics Society
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• v.19 no.4
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• pp.142-146
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• 2009

The soft magnetic property for the Corning glass/Ta(5 nm)/[Conetic, Permalloy)/Ta(3 nm) prepared by the ion beam deposition sputtering was investigated. The coercivity and saturation magnetic field of conetic (NiFeCuMo) and permalloy (NiFe) layer with easy and hard direction along to the applying magnetic field during deposition was compared with each other. The surface resistance of conetic film with a thickness of 10 nm was 2 times lower than one of permalloy film. The coercivity and the magnetic susceptibility of conetic film decreased and increased 3 times to one of permalloy film, respectively. These results suggest that a highly sensitive GMR-SV or MTJ using conetic film can be possible to develop the bio-device.