Size effect of inserted iron nanoparticles in the MgO-based double barrier magnetic tunnel junction

Yen Chi Lee, Chia Hao Lin, A. K. Mishra, Te Ho Wu, Jong-Ching Wu

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The transport properties of stacked CoFeB (1.86)/MgO (0.2)/Fe-nanoparticles (tFe)/MgO (0.5)/CoFeB(0.6) double barrier magnetic tunnel junctions have been characterized. In this investigation, stacked film is prepared by magnetron sputter system, annealed at 250°, and patterned into a micron-scale device using standard electron beam lithography in conjunction with two-angle ion beam etching. First, the structure, magnetic and electrical properties are examined by using transmission electron microscopy, alternating gradient magnetometers, and lock-in techniques. Stacked film having 1.5 nm lateral size of iron nanoparticles (sample S1) exhibits an in-plane magnetic anisotropy, nonetheless the stacked film having 2 nm lateral size of iron nanoparticles (sample S5) possesses out-of-plane magnetic anisotropy. In addition, the micron scaled S1 device displays not only a normal in-plane magnetoresistance (MR) curve but also an anomalous out-of-plane MR behavior, whereas the S5 device only barely shows magnetic response in the in-plane MR. A hysteresis-free linear region in out-of-plane MR curve has shown field sensitivity of ∼ 36 Ω/Oe that is promising for magnetic field sensor applications.

Original languageEnglish
Article number2276014
JournalIEEE Transactions on Magnetics
Volume50
Issue number1
DOIs
Publication statusPublished - 2014 Jan 1

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Tunnel junctions
Magnetoresistance
Iron
Nanoparticles
Magnetic anisotropy
Electron beam lithography
Magnetometers
Transport properties
Ion beams
Hysteresis
Etching
Magnetic properties
Electric properties
Display devices
Magnetic fields
Transmission electron microscopy
Sensors

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Electrical and Electronic Engineering

Cite this

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title = "Size effect of inserted iron nanoparticles in the MgO-based double barrier magnetic tunnel junction",
abstract = "The transport properties of stacked CoFeB (1.86)/MgO (0.2)/Fe-nanoparticles (tFe)/MgO (0.5)/CoFeB(0.6) double barrier magnetic tunnel junctions have been characterized. In this investigation, stacked film is prepared by magnetron sputter system, annealed at 250°, and patterned into a micron-scale device using standard electron beam lithography in conjunction with two-angle ion beam etching. First, the structure, magnetic and electrical properties are examined by using transmission electron microscopy, alternating gradient magnetometers, and lock-in techniques. Stacked film having 1.5 nm lateral size of iron nanoparticles (sample S1) exhibits an in-plane magnetic anisotropy, nonetheless the stacked film having 2 nm lateral size of iron nanoparticles (sample S5) possesses out-of-plane magnetic anisotropy. In addition, the micron scaled S1 device displays not only a normal in-plane magnetoresistance (MR) curve but also an anomalous out-of-plane MR behavior, whereas the S5 device only barely shows magnetic response in the in-plane MR. A hysteresis-free linear region in out-of-plane MR curve has shown field sensitivity of ∼ 36 Ω/Oe that is promising for magnetic field sensor applications.",
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Size effect of inserted iron nanoparticles in the MgO-based double barrier magnetic tunnel junction. / Lee, Yen Chi; Lin, Chia Hao; Mishra, A. K.; Wu, Te Ho; Wu, Jong-Ching.

In: IEEE Transactions on Magnetics, Vol. 50, No. 1, 2276014, 01.01.2014.

Research output: Contribution to journalArticle

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