Interlayer exchange coupling dependence of thermal stability parameters in synthetic antiferromagnetic free layers

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:303

Article

Saito, Y ; Sugiyama, H ; Inokuchi, T ; Inomata, K

关键词: thermal stability parameters;    synthetic antiferromagnetic free layers;    magnetic tunnel junctions;    interlayer exchange coupling;   

DOI  :  10.1016/j.jmmm.2005.10.227

来源: Elsevier

【 摘 要 】

We conducted a detailed comparative study of thermal stability properties over a thermal excitation of switching of the free layer in a magnetic tunnel junction (MTJ) with Ni81Fe19, Co90Fe10, and synthetic antiferromagnetic (Syn-AF) free layers with several strengths of interlayer exchange coupling (J(EX)). The thermal stability properties were investigated using the junction magnetoresistance of current-perpendicular MTJ devices with a word line as probes. The observed sweep-rate-dependent coercivities were analyzed using the Sharrock formula. The results confirmed strong J(EX) dependence on thermal stability parameters (KuV/kT) in Syn-AF free layers. The values of KuV/k(B)T for MTJs with Syn-AF free layers decreased with a decrease in the strength of J(EX), and the increase in the effective volume of the Syn-AF free layer disappeared at J(EX) <= 0.52 erg/cm(2). The Syn-AF free layer with J(EX)>0.52 erg/cm(2) is relevant for high-density spin electronic nanodevices with a low aspect ratio. (C) 2005 Elsevier B.V. All rights reserved.

【 授权许可】

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