Transport properties of low resistance underoxidized magnetic tunnel junctions

• Type: Article in International Scientific Journal
• Date: 2007

Authors

ventura, j. (Author) Other; ferreira, r. (Author) Other; teixeira, j. m. (Author) Other; pereira, a. m. (Author) Other; araujo, j. p. (Author) FCUP; pogorelov, y. (Author) FCUP; sousa, j. b. (Author) FCUP; freitas, p. p. (Author) Other

Journal

Title: IEEE Transactions on Magnetics

Vol. 43

Pages: 2815-2817

ISSN: 0018-9464

Publisher: IEEE

Indexing

ISI Web of Knowledge - 1 Citation

Scopus - 1 Citation

Other information

Authenticus ID: P-004-9QJ

DOI: 10.1109/tmag.2007.893699

Abstract (EN): Magnetic tunnel junctions (MTJs) are currently replacing spin valves as read sensors in high density media. To be implemented, MTJs must have low resistance-area product (R x A) and reasonable tunnel magnetoresistance (TMR) which are usually obtained using ultra-thin barriers. The use of thicker, underoxidized AlOx barriers can also lead to similarly suitable MTJ-characteristics. Here we study the temperature dependence of the transport properties of 9 angstrom underoxidized magnetic tunnel junctions, revealing the dominance of different transport mechanisms in different samples of the same wafer: tunnel, metallic or a mixture of the two, depending on MTJ-magnetic state. Such differences likely arise from slight structural differences inherent to the oxidation process. We further show that the MR-temperature dependence is stronger for MTJs displaying a metallic-like behavior(dR/dT > 0) and compare such behavior with the enhanced MR(T) observed in current perpendicular to the plane (CPP) spin valves.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 3