• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2005.05a
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• pp.324-328
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• 2005

스핀 밸스 트랜지스터를 소형화 할 수 있는 공정 기술을 소개한다. 스핀 밸브 트랜지스터는 두 개의 실리콘 에미터, 컬렉터 사이에 다층 자성 금속 박막이 존재하는 구조를 갖고 있는 스핀트로닉스 소자이다. SU8을 절연층으로 사용한 접촉 패드의 도입, 실리콘 온 인슐레이터의 사용, 그리고 이온빔/습식 복합에칭 공정의 적용으로 수 ${\mu}m$까지 소형화 할 수 있었다. 트랜지스터의 소형화에 따른 특성 변화는 관찰되지 않았으며, 기존의 트랜지스터와 동일한 $240\%$의 자기전류값을 나타내었다.

• Proceedings of the Korean Magnestics Society Conference
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• 2002.12a
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• pp.162-163
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• 2002

거대자기저항(GMR) 분야에서 높은 GMR 값을 보유하는 것은 주요 관심사이다. Egelhoff와 연구자들은 산소를 이용하여 스핀밸브 박막의 표면을 산화시켜 유도 전자들의 Specular 산란 효과를 보고하였으며, 강자성층과 산화층 사이의 계면에서 specular 반사가 이루어져 GMR의 향상을 가져온 것으로 보고 있다[1,2]. 또한 annealing에 따른 자기적 특성의 향상과에 관한 논문도 보고되어진 바 있다[4]. (중략)

• Proceedings of the Korean Magnestics Society Conference
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• 2017.05a
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• pp.71-72
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• 2017

• Proceedings of the Korean Magnestics Society Conference
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• 2005.06a
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• pp.170-171
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• 2005

• Proceedings of the Korean Magnestics Society Conference
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• 2008.12a
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• pp.146.1-146.1
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• 2008

• Proceedings of the Korean Magnestics Society Conference
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• 2008.12a
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• pp.147.1-147.1
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• 2008

• Proceedings of the Korean Magnestics Society Conference
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• 2002.12a
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• pp.150-151
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• 2002

In recent years, semi-metallic Bismuth (Bi) has attracted significant attention due to very large magnetoresistance (MR) at room temperature originating from long carrier mean free path l and small effective carrier mass m＊[1, 2]. In particular, the MR behavior and long carrier mean free path l in Bi thin films can be exploited for spintronic devices, e.g. magnetic field sensors and spin-valve transistors. In present work, we present the magnetotransport properties of the electroplated and sputtered Bi thin films in the temperature range 4-300 K. (omitted)

• Journal of the Korean Magnetics Society
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• v.10 no.2
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• pp.67-73
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• 2000

Top spin valve samples with a structure Ta/NiFe/CoFe/Cu/CoFe/FeMn/Ta were deposited on a Si(100) substrate by changing d.c. magnetron sputtering conditions and the exchange-bias and magnetic properties of samples were investigated. The Exchange field, H$\_$ex/ increased with increase of sputtering power of FeMn from 30 to 150 W and CoFe from 30 to 100 W deposited on the Cu, the increase of H$\_$ex/ was found due to the improvement of preferred orientation of (111) FeMn phase from XRD results. In the case of Cu, H$\_$ex/ decreased with the increase of sputtering pressure ranging from 1 to 5 mTorr. The relationship between exchange field and resistance was investigated, spin valve samples with a large exchange field showed the lower resistance, which was strongly dependent on the good crystallinity and grain size increase as well as lower scattering effects. The Cu thickness was changed from 22 to 38 $\AA$ for Si/Ta/NiFe/CoFe/Cu(t), 30 W/CoFe, 100 W/FeMn, 100 W/Ta spin valve structures, MR ratio of 6.5 % and exchange field of about 190 Oe were obtained for the sample with Cu of 22 $\AA$ thickness. The increase of exchange field with decrease of Cu thickness was explained by FM/AFM spin-spin interaction.

• Journal of the Korean Magnetics Society
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• v.12 no.3
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• pp.103-108
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• 2002

We investigated magnetoresistance(MR) and exchange bias properties by annealing in top and bosom type spin valves (SV) with nano-oxide layers (NOL). In top SVs with NOL, MR ratio of 9.2% is obtained after postdeposition annealing at 250$\^{C}$. In bottom SVs with NOL, MR ratio of 10.1 % is obtained after postdeposition annealing at 250$\^{C}$. Therefore, specular reflection of the NOL in bottom SVs is higher than that of the NOL in top SVs. Exchange biasing of bottom SVs with NOL is 28% higher than that of bottom SVs without NOL after annealing. This enhancement of exchange biasing is thought to be due to the reduced magnetic moment of the pinned layer with NOL and enhanced (111) FeMn texture.

• Journal of the Korean Magnetics Society
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• v.10 no.1
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• pp.37-41
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• 2000

We investigated the magnetoresistance effect and the exchange coupling of antiferromagnetic Fe$_2$O$_3$ spin-valve film. The X-ray diffractions of the spin-valve films having a different thickness of a $\alpha$-Fe$_2$O$_3$ were measured. The exchange coupling field (H$_{ex}$) between Fe$_2$O$_3$ and pinned NiFe layer was increased from 13.5 Oe to 84.5 Oe, as the thickness of Fe$_2$O$_3$ increased from 400 $\AA$ to 800 $\AA$. The surface roughness of $\alpha$-Fe$_2$O$_3$spin-valves increased with the increase of $\alpha$-Fe$_2$O$_3$thickness. Therefore, the increase of H$_{ex}$ will be due to the increase of the interface roughness. The MR ratios as a function of Fe$_2$O$_3$ thickness was not changed. And H$_{ex}$ increased by the increment of magnetostatic coupling between Fe$_2$O$_3$ and NiFe (pinned-layer) due to the increment of interface roughness. H$_{ex}$ depends on the surface roughness, but the magnetoresistance ratio doesn't doesn't.