Perpendicular magnetic anisotropy in Ta|Co{sub 40}Fe{sub 40}B{sub 20}|MgAl{sub 2}O{sub 4} structures and perpendicular CoFeB|MgAl{sub 2}O{sub 4}|CoFeB magnetic tunnel junction

Journal Article · Mon Sep 08 00:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4895671· OSTI ID:22310833

Tao, B. S.; Li, D. L.; Yuan, Z. H.; Liu, H. F.; Ali, S. S.; Feng, J. F.; Wei, H. X.; Liu, Y.; Zhao, Y. G. ^[1]; Zhang, Q.; Guo, Z. B. ^[2]; Zhang, X. X. ^[2]

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1. Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University, Beijing 100084 (China)
2. Advanced Nanofabrication, Imaging and Characterization Core Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 239955 (Saudi Arabia)

Magnetic properties of Co{sub 40}Fe{sub 40}B{sub 20} (CoFeB) thin films sandwiched between Ta and MgAl{sub 2}O{sub 4} layers have been systematically studied. For as-grown state, Ta/CoFeB/MgAl{sub 2}O{sub 4} structures exhibit good perpendicular magnetic anisotropy (PMA) with interface anisotropy K{sub i} = 1.22 erg/cm{sup 2}, which further increases to 1.30 erg/cm{sup 2} after annealing, while MgAl{sub 2}O{sub 4}/CoFeB/Ta multilayer shows in-plane magnetic anisotropy and must be annealed in order to achieve PMA. For bottom CoFeB layer, the thickness window for PMA is from 0.6 to 1.0 nm, while that for top CoFeB layer is between 0.8 and 1.4 nm. Perpendicular magnetic tunnel junctions (p-MTJs) with a core structure of CoFeB/MgAl{sub 2}O{sub 4}/CoFeB have also been fabricated and tunneling magnetoresistance ratio of about 36% at room temperature and 63% at low temperature have been obtained. The intrinsic excitations in the p-MTJs have been identified by inelastic electron-tunneling spectroscopy.

• OSTI ID: 22310833
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 10 Vol. 105; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALUMINATES
ANISOTROPY
ANNEALING
BORON COMPOUNDS
COBALT COMPOUNDS
ELECTRON SPECTROSCOPY
EXCITATION
INTERFACES
IRON COMPOUNDS
LAYERS
MAGNESIUM COMPOUNDS
MAGNETIC PROPERTIES
MAGNETORESISTANCE
TANTALUM
TEMPERATURE RANGE 0273-0400 K
THICKNESS
THIN FILMS
TUNNEL DIODES
TUNNEL EFFECT