• Journal of Magnetics
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• 제2권3호
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• pp.96-100
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• 1997

A spin valve structure of NiO(40 nm)/Co(2 nm)/Cu(2.6 nm)/Co(x nm)/Ta(5 nm) has been investigated for the application of magnetic random access memory (MRAM). The spin valve structure exhibited very large difference in the coercivities between pinned and free layers, a relatively high GMR ratio, and a low free layer coercivity. The spin valves were prepared by sputtering and were characterized by dc 4-point probe, and VSM. The spin valves with combined free layer exhibited a maximun GMR ratio of 10.4% with a free layer coercivity of about 82 Oe. The spin valves with a single 10 nm thick a-CoNbZr free layer exhibited a GMR ratio of about 4.3% with a free layer coercivity of about 12 Oe. The GMR ratio of the spin valves increased by addition of Co between Cu and a-CoNbZr. It has been confirmed that the coercivity of free layer can be decreased by increasing the thickness of a-CoNbZr. It has been confirmed that the coercivity of free layer can be decreased by increasing the thickness of a-CoNbZr layer without losing the GMR ratio substantially, which was mainly due to high resistivity of the amorphous "layers".

• 한국자기학회:학술대회 개요집
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• 한국자기학회 1998년도 추계연구발표회 논문개요집
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• pp.14-15
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• 1998

• Journal of Magnetics
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• 제13권1호
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• pp.30-33
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• 2008

A highly sensitive, giant magnetoresistance-spin valve (GMR-SV) biosensing device with high linearity and very low hysteresis was fabricated by photolithography. The detection of magnetic nanoparticles and Fe-hemoglobin inside red blood cells using the GMR-SV biosensing device was investigated. When a sensing current of 1 mA was applied to the current electrode in the patterned active devices with an area of $2{\times}6{\mu}m^2$, the output signals were about 13.35 mV. The signal from even one drop of human blood and nanoparticles in distilled water was sufficient for their detection and analysis.

• 한국결정성장학회지
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• 제8권1호
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• pp.73-82
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• 1998

교환이방성이란 반강자성층과 강자성층의 이층막(bilayer)사이의 교환작용에 의해 발생하는 일방향 자기이방성을 말한다. 본 연구에서는 스퍼터링법으로 제작한 NiO/NiFe 이층막에서 발생하는 교환이방성에 대한 연구를 통하여 이를 스핀밸브형 거대자기저항 소자에 적용하고자 하였다. 먼저 NiO 증착조건 변화에 따른 NiO/NiFe 이층막의 특성변화를 살펴보았으며, 이를 통하여 NiO 증착중 Ar 압력 변화가 이층막의 교환이방성에 가장 중요한 인자임을 알수 있었다. 즉 Ar 압력이 낮을수록 교환이방성 특성이 더 우수하였다. 이러한 이층막 조건을 통하여 스핀밸브형 거대자기저항 다층막을 증착하였으며 그 결과 3.4%의 자기저항비와 0.25%/Oe의 민감도를 얻었다.

• Journal of Magnetics
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• 제16권4호
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• pp.328-331
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• 2011

Here, we describe a dual spin valve structure with distinct switching fields for two pinned layers. A device with this structure has a staircase of three distinct magnetoresistive states. The multiple resistance states are achieved by controlling the exchange coupling between two ferromagnetic pinned layers and two adjacent anti-ferromagnetic pinning layers. The maximum magnetoresistance ratio is 7.9% for the current-perpendicular-to-plane and 7.2% for the current-in-plane geometries, with intermediate magnetoresistance ratios of 3.9% and 3.3%, respectively. The requirements for using this exchange-biased stack as a three-state memory device are also discussed.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 1996년도 추계연구발표회 논문개요집
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• pp.36-37
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• 1996

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2001년도 춘계연구발표회 논문개요집
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• pp.46-47
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• 2001

• Journal of Magnetics
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• 제22권1호
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• pp.7-13
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• 2017

The magnetoresistance (MR) properties of antiferromagnetic (AFM) IrMn based giant magnetoresistance-spin valve (GMR-SV) was investigated in view point of the artificial rotation effect of ferromagnetic (FM) layer in the plane induced by an applied field during the post annealing temperature. The MR curves measured with an azimuthal angle region of ${\phi}=0^{\circ}-360^{\circ}$ are depended on the annealing temperature and the magnetization easy axis of two free NiFe layers and two pinned NiFe layers in dual-type GMR-SV film. Especially, the annealing temperature and sample rotation angle(${\theta}$ ) maintained to the magnetic sensitivity (MS) of 1.4 %/Oe with an isotropic region angle of $110^{\circ}$ are $100^{\circ}C$ and $90^{\circ}$, respectively.

• Journal of Magnetics
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• 제11권3호
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• pp.108-110
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• 2006

We successfully enhanced the performance of a spin valve by inserting an ultra-thin layer of partially oxidized Fe in the pinned and free layers. With the exchange bias field kept large, the spin valve reached a GMR of 12%, which corresponded to a 55% increase in GMR when we compared it with that of spin valves without any inserted layer. The layer of partially oxidized Fe was more effective for improving the properties of the spin valve than the layer of partially oxidized $Co_{90}Fe_{10}$. Considering all the results, we can contribute the significant improvement to the combined effect of the modified local electronic structures at the Fe impurities and theenhanced spin-dependent reflections at the $\alpha-Fe_{2}O_{3} phase in the magnetic layer.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2000년도 International Symposium on Magnetics The 2000 Fall Conference
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• pp.303-304
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• 2000