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X-ray photoemission study of CoFeB/MgO thin film bi-layers

J. C. Read·P. G. Mather·R. A. Buhrman
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Abstract

We present results from an X-ray photoemission spectroscopy (XPS) study of CoFeB/MgO bi-layers where we observe process-dependent formation of B, Fe, and Co oxides at the CoFeB/MgO interface due to oxidation of CoFeB during MgO deposition. Vacuum annealing reduces the Co and Fe oxides but further incorporates B into the MgO forming a composite MgBxOy layer. Inserting an Mg layer between CoFeB and MgO introduces an oxygen sink, providing increased control over B content in the barrier.

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J. C. Read, P. G. Mather, R. A. Buhrman. 2007-02-09. X-ray photoemission study of CoFeB/MgO thin film bi-layers. https://arxiv.org/abs/cond-mat/0702232

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