Determination of the thickness of Al₂O₃ barriers in magnetic tunnel junctions

Buchanan, J.D.R.; Hase, T.P.A.; Tanner, B.K.; Hughes, N.D.; Hicken, R.J.

Abstract

The barrier thickness in magnetic spin-dependent tunnel junctions with Al2O3 barriers has been measured using grazing incidence x-ray reflectivity and by fitting the tunneling current to the Simmons model. We have studied the effect of glow discharge oxidation time on the barrier structure, revealing a substantial increase in Al2O3 thickness with oxidation. The greater thickness of barrier measured using grazing incidence x-ray reflectivity compared with that obtained by fitting current density-voltage to the Simmons electron tunneling model suggests that electron tunneling is localized to specific regions across the barrier, where the thickness is reduced by fluctuations due to nonconformal roughness.

Citation

Buchanan, J., Hase, T., Tanner, B., Hughes, N., & Hicken, R. (2002). Determination of the thickness of Al₂O₃ barriers in magnetic tunnel junctions. Applied Physics Letters, 81(4), 751-753. https://doi.org/10.1063/1.1496131

• Journal Article Type: Article
• Publication Date: Jul 22, 2002
• Deposit Date: Jan 9, 2009
• Publicly Available Date: Apr 21, 2011
• Journal: Applied Physics Letters
• Print ISSN: 0003-6951
• Electronic ISSN: 1077-3118
• Publisher: American Institute of Physics
• Peer Reviewed: Peer Reviewed
• Volume: 81
• Issue: 4
• Pages: 751-753
• DOI: https://doi.org/10.1063/1.1496131
• Keywords: Aluminum oxides, Cobalt, Electron spin, Electron tunneling, Ferromagnetic materials, Grazing incidence, Insulation, Insulators, Magnetic materials, Magnetic properties, Magnetoresistivity, MIM (semiconductors), Permalloys (trademark), Polarization.
• Public URL: https://durham-repository.worktribe.com/output/1618900
• Publisher URL: http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2002ApPhL..81..751B&db_key=PHY