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Title: In situ transport measurements of plasma-oxidized MgO magnetic tunnel junctions during the annealing process

Abstract

The postdeposition annealing of magnetic tunnel junctions has become standard practice in junction fabrication to improve barrier properties. We have performed tunneling measurements at elevated temperatures during the annealing process on plasma-oxidized, MgO barrier, magnetic tunnel junctions. The data were interpreted in terms of the Hartman model which accounts for an asymmetric barrier profile. The results could not be interpreted solely by the temperature smearing of the Fermi distribution and so the electrode/barrier/electrode structure had been altered during the annealing. While the barrier height at one interface improved, the other was degraded. Our experiments lead us to believe that this is due to the diffusion of Mn to the barrier/pinned electrode interface. We show that through transport and tunneling magnetoresistance measurements it is possible to monitor physical processes such as material migration during the annealing process.

Authors:
; ; ;  [1]
  1. School of Physics and Astronomy, E. C. Stoner Laboratory, University of Leeds, Leeds LS2 9JT (United Kingdom)
Publication Date:
OSTI Identifier:
20788151
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 99; Journal Issue: 8; Other Information: DOI: 10.1063/1.2166601; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANNEALING; ASYMMETRY; DIFFUSION; ELECTRODES; FABRICATION; INTERFACES; MAGNESIUM OXIDES; MAGNETORESISTANCE; OXIDATION; PLASMA; SUPERCONDUCTING JUNCTIONS; TUNNEL EFFECT

Citation Formats

Anderson, G. I. R., Hindmarch, A. T., Marrows, C. H., and Hickey, B. J.. In situ transport measurements of plasma-oxidized MgO magnetic tunnel junctions during the annealing process. United States: N. p., 2006. Web. doi:10.1063/1.2166601.
Anderson, G. I. R., Hindmarch, A. T., Marrows, C. H., & Hickey, B. J.. In situ transport measurements of plasma-oxidized MgO magnetic tunnel junctions during the annealing process. United States. doi:10.1063/1.2166601.
Anderson, G. I. R., Hindmarch, A. T., Marrows, C. H., and Hickey, B. J.. Sat . "In situ transport measurements of plasma-oxidized MgO magnetic tunnel junctions during the annealing process". United States. doi:10.1063/1.2166601.
@article{osti_20788151,
title = {In situ transport measurements of plasma-oxidized MgO magnetic tunnel junctions during the annealing process},
author = {Anderson, G. I. R. and Hindmarch, A. T. and Marrows, C. H. and Hickey, B. J.},
abstractNote = {The postdeposition annealing of magnetic tunnel junctions has become standard practice in junction fabrication to improve barrier properties. We have performed tunneling measurements at elevated temperatures during the annealing process on plasma-oxidized, MgO barrier, magnetic tunnel junctions. The data were interpreted in terms of the Hartman model which accounts for an asymmetric barrier profile. The results could not be interpreted solely by the temperature smearing of the Fermi distribution and so the electrode/barrier/electrode structure had been altered during the annealing. While the barrier height at one interface improved, the other was degraded. Our experiments lead us to believe that this is due to the diffusion of Mn to the barrier/pinned electrode interface. We show that through transport and tunneling magnetoresistance measurements it is possible to monitor physical processes such as material migration during the annealing process.},
doi = {10.1063/1.2166601},
journal = {Journal of Applied Physics},
number = 8,
volume = 99,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}
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