Electric breakdown in ultrathin MgO tunnel barrier junctions for spin-transfer torque switching

Journal Article · Mon Dec 07 00:00:00 EST 2009 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.3272268· OSTI ID:21294500

Schaefers, M; Drewello, V; Reiss, G; Thomas, A ^[1]; Thiel, K ^[2]; Eilers, G; Muenzenberg, M; Schuhmann, H; Seibt, M ^[3]

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1. Department of Physics, Thin Films and Physics of Nanostructures, Bielefeld University, 33501 Bielefeld (Germany)
2. Fraunhofer Institut fuer Fertigungstechnik und Angewandte Materialforschung, Wiener Str. 12, 28359 Bremen (Germany)
3. I. and IV. Physikalisches Institut and Sonderforschungsbereich 602, Friedrich-Hund-Platz 1, Georg-August-Universitaet Goettingen, 37077 Goettingen (Germany)

Magnetic tunnel junctions for spin-transfer torque (STT) switching are prepared to investigate the dielectric breakdown. Intact and broken tunnel junctions are characterized by transport measurements prior to transmission electron microscopy analysis. The comparison to our previous model for thicker MgO tunnel barriers reveals a different breakdown mechanism arising from the high current densities in a STT device: instead of local pinhole formation at a constant rate, massive electromigration and heating leads to displacement of the junction material and voids are appearing. This is determined by element resolved energy dispersive x-ray spectroscopy and three dimensional tomographic reconstruction.

• OSTI ID: 21294500
• Journal Information: Applied Physics Letters, Vol. 95, Issue 23; Other Information: DOI: 10.1063/1.3272268; (c) 2009 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BORON ALLOYS
CHEMICAL ANALYSIS
COBALT ALLOYS
COPPER COMPOUNDS
CURRENT DENSITY
DIELECTRIC MATERIALS
ELECTROPHORESIS
IRON ALLOYS
MAGNESIUM OXIDES
MANGANESE ALLOYS
PLATINUM ALLOYS
RUTHENIUM
SPIN
SUPERCONDUCTING JUNCTIONS
TANTALUM
TORQUE
TRANSMISSION ELECTRON MICROSCOPY
TUNNEL EFFECT
X-RAY SPECTROSCOPY