• Title/Summary/Keyword: Spin valve

Search Result 227, Processing Time 0.025 seconds

Magnetoresistance of Co/Cu/Co Spin Valve Sandwiches

  • Park, S. J.;Park, K. L.;Kim, M. Y.;j. R. Rhee;D. G. Hwang;Lee, S. S.;Lee, k. A.;Park, C. M.
    • Journal of Magnetics
    • /
    • v.2 no.1
    • /
    • pp.7-11
    • /
    • 1997

  • The dependence of magnetoresistance (MR) ratio on various variables like the thickness of the second Co layer, on the presence of cap layer, on deposition field (Hdep) and on annealing in Co/Cu/Co sandwiches was investigated. Spin-valve sandwiches were deposited on the corning glass by means of the 3-gun dcmagnetron sputtering at a 5 mTorr partial Ar pressure and room temperature. The deposition field was varied from 70 Oe to 720 Oe. The MR curve was measured by the four-terminal method with applied magnetic field up to 1000 Oe perpendicular to the direction of a current in the film plne. The MR ratio of glass/Fe(50${\AA}$)/Co(17${\AA}$)/Cu(24${\AA}$)/Cot(${\AA}$) fabricated by making 50 ${\AA}$ of Fe buffer layer has the maximum value of 8.2% when the thickness of the second Co layer was 17${\AA}$and the deposition field was 350 Oe. In the case of glass/Fe(50${\AA}$)/Co(17${\AA}$)/Cu(24${\AA}$)/Cot(${\AA}$) with Cu cap layer on top, the decrease in the MR ratio seemed to relate with the oxidation of the second Co layer. Samples prepared with deposition field showed greater MR ratios through the formation of more complete spin valve films. After annealing for 2 hours at 300$^{\circ}C$, the MR ratio of the samples prepared with deposition field decreased rapidly while the MR raito of the sample prepared without the field remained.

  • PDF

Post Annealing Treatment Introducing an Isotropy Magnetorsistive Property of Giant Magnetoresistance-Spin Valve Film for Bio-sensor (바이오센서용 거대자기저항-스핀밸브 박막이 등방성 자기저항 특성을 갖게 하는 후열처리 조건 연구)

  • Khajidmaa, P.;Park, Kwang-Jun;Lee, Sang-Suk
    • Journal of the Korean Magnetics Society
    • /
    • v.23 no.3
    • /
    • pp.98-103
    • /
    • 2013

  • The magnetic easy axis of the ferromagnetic layer for the dual-type GMR-SV (giant magnetoresistance-spin valve) having NiFe/Cu/NiFe/IrMn/NiFe/Cu/NiFe multuilayer structure controlled by the post annealing treatment. The magnetoresistive curves of a dual-type IrMn based GMR-SV depending on the direction of the magnetic easy axis of the free and the pinned layers are measured by the different angles for the applied fields. By investigating the switching process of magnetization for an arbitrary measuring direction, the optimum annealing temperature having a steady and isotropy magnetic sensitivity of 2.0 %/Oe was $105^{\circ}C$. This result suggests that the in-plane orthogonal magnetization for the dual-type GMR-SV film can be used by a high sensitive biosensor.

  • https://doi.org/10.4283/JKMS.2013.23.3.098 인용 PDF KSCI

Magnetic Sensitivity Depending on Width of IrMn Spin Valve Film Device (IrMn 스핀밸브 박막소자의 폭 크기에 의존하는 자장감응도)

  • Choi, Jong-Gu;Lee, Sang-Suk
    • Journal of the Korean Magnetics Society
    • /
    • v.20 no.2
    • /
    • pp.41-44
    • /
    • 2010

  • The Cu thickness dependence of magnetic sensitivity for the NiFe/Cu/NiFe/IrMn spin valve multilayer was investigated. The magnetic properties measured by minor MR curves for the Ta(5 nm)/NiFe(8 nm)/Cu(3.5 nm)/NiFe(4 nm)/IrMn(8 nm)/Ta(2.5 nm) multilayer is MR = 1.46 %, MS = 2.0 %/Oe, $H_c\;=\;2.6\;Oe$, and $H_{int}\;=\;0.1\;Oe$. The magnetic sensitivities of GMR-SV devices with ten different widths and a same length of $4.45\;{\mu}m$ by fabricated by photo lithography decreased from 0.3 %/Oe to 0.06%/Oe as from a width of $10\;{\mu}m$ to $1\;{\mu}m$.

  • https://doi.org/10.4283/JKMS.2010.20.2.041 인용 PDF KSCI

A Study on the Analysis of Magnetoresistive Behavior in Giant Magnetoresistive Spin Valve Trilayer Films (거대자기저항 스핀밸브 삼층박막의 자기저항 거동 해석에 관한 연구)

  • 김형준;이병일;주승기
    • Journal of the Korean Magnetics Society
    • /
    • v.8 no.4
    • /
    • pp.224-230
    • /
    • 1998

  • The relationships between R-H curves of gaint magnetoresistance (GMR) spin valve trilayer films and M-H curves of each magnetic layer consisting of the trilayer films were analyzed and simple formula representing the relations between the curves were suggested for theoretical analysis and study of magnetoresistance (MR) in those films, especially where the MR is from the difference of coercivity. Using two kinds of NiFe/Cu/Co films, which had been deposited on Cu(50 $\AA$)/Si(111, 4$^{\circ}$ tilt-cut) and Cu(50 $\AA$)/glass, R-H and M-H curves were measured and compared with the calculated ones, which were obtained by appying the M-H curves of single NiFe and Co films, deposited on the same substrates, to the previously reported single-domain and multi-domain models. The calcuated ones were well consistent with the measured ones and the suggested simple relationships between R-H and M-H curves are thought to be very useful for the deep understanding of MR behavior and the reasonable approach to improve MR properties in GMR spin valve trilayer films.

  • PDF

Giant interlayer tunneling magnetoresistance in layered manganite

  • Won, C.J.;Yang, J.J.;Cheong, S.W.;Hur, N.
    • Proceedings of the Korean Magnestics Society Conference
    • /
    • 2015.05a
    • /
    • pp.156-157
    • /
    • 2015

  • we have presented the enhanced interlayer tunneling magnetoresistance in doped $La_{1+2x}Sr_{2-2x}Mn_2O_7$ single crystal below $T_C$. The drastically out-of-plane magnetoresistance observed in magnetic fields perpendicular to the bilayers indicates that spin-polarized magnetic layers in single crystal show as a stack of ordered spin valve.

  • PDF