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arXiv · 1208.5828

CoFeB Thickness Dependence of Thermal Stability Factor in CoFeB/MgO Perpendicular Magnetic Tunnel Junctions

H. Sato·M. Yamanouchi·K. Miura·S. Ikeda·R. Koizumi·F. Matsukura·H. Ohno
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Abstract

Thermal stability factor (delta) of recording layer was studied in perpendicular anisotropy CoFeB/MgO magnetic tunnel junctions (p-MTJs) with various CoFeB recording layer thicknesses and junction sizes. In all series of p-MTJs with different thicknesses, delta is virtually independent of the junction sizes of 48-81 nm in diameter. The values of delta increase linearly with increasing the recording layer thickness. The slope of the linear fit is explained well by a model based on nucleation type magnetization reversal.

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H. Sato, M. Yamanouchi, K. Miura, S. Ikeda, R. Koizumi, F. Matsukura, H. Ohno. 2012-08-29. CoFeB Thickness Dependence of Thermal Stability Factor in CoFeB/MgO Perpendicular Magnetic Tunnel Junctions. https://doi.org/10.1109/lmag.2012.2190722

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