Influence of electrode structure on magnetotransport in magnetic tunnel junctions

Author

Wieldraaijer, H. ; LeClair, P. ; Kohlhepp, J.T. ; Swagten, H.J.M. ; de Jonge, W.J.M.

Author_Institution

Dept. of Appl. Phys., Eindhoven Univ. of Technol., Netherlands

Volume

38

Issue

5

fYear

2002

fDate

9/1/2002 12:00:00 AM

Firstpage

2727

Lastpage

2729

Abstract

The physical structure of the magnetic electrodes of Co-Al₂O₃-Co magnetic tunnel junctions has been investigated by. means of ⁵⁹Co nuclear magnetic resonance and X-ray diffraction. Junctions sputtered on FeMn have an essentially fcc [111]-oriented bottom electrode, while all top electrodes and the bottom electrodes of junctions sputtered on Ta are polyphase and polycrystalline. The specifics of the electronic structure of the electrode crystal phases can explain the extra features and asymmetry in the conductance-versus-bias behavior observed in FeMn-based junctions.

Keywords

MIM structures; X-ray diffraction; aluminium compounds; cobalt; electrodes; ferromagnetic materials; giant magnetoresistance; magnetic multilayers; nuclear magnetic resonance; sputtered coatings; tunnelling; Co-Al₂O₃-Co; X-ray diffraction; differential junction conductances; electrode structure influence; ferromagnetic junctions; hyperfine fields; magnetic electrodes; magnetic tunnel junctions; magnetotransport; nuclear magnetic resonance; sputtered electrodes; stacking-fault phases; Amorphous magnetic materials; Atomic measurements; Electrodes; Helium; Magnetic analysis; Magnetic resonance; Magnetic tunneling; Nuclear electronics; Nuclear magnetic resonance; X-ray diffraction;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2002.803162

Filename

1042334