Fe diffusion, oxidation, and reduction at the CoFeB/MgO interface studied by soft x-ray absorption spectroscopy and magnetic circular dichroism

被引：39

作者：

Hindmarch, A. T. ^{[1
]}

Dempsey, K. J. ^{[1
]}

Ciudad, D. ^{[1
]}

Negusse, E. ^{[2
]}

Arena, D. A. ^{[3
]}

Marrows, C. H. ^{[1
]}

机构：

[1] Univ Leeds, Sch Phys & Astron, Leeds LS2 9JT, W Yorkshire, England

[2] Montana State Univ, Dept Phys, Bozeman, MT 59717 USA

[3] Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA

来源：

APPLIED PHYSICS LETTERS | 2010年 / 96卷 / 09期

基金：

英国工程与自然科学研究理事会;

关键词：

cobalt compounds; diffusion; ferromagnetic materials; interface magnetism; iron compounds; magnesium compounds; magnetic annealing; magnetic circular dichroism; magnetic tunnelling; magnetisation; oxidation; reduction (chemical); X-ray absorption spectra; ROOM-TEMPERATURE; TUNNEL-JUNCTIONS; MAGNETORESISTANCE; BARRIERS;

D O I：

10.1063/1.3332576

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

We have studied the effect of annealing on the interface magnetization in a CoFeB/MgO structure which models the lower electrode in a magnetic tunnel junction device. We find that MgO deposition causes Fe to diffuse toward the CoFeB/MgO interface, where it preferentially bonds with oxygen to form a Fe-O-rich interfacial region with reduced magnetization. After annealing at 375 degrees C the compositional inhomogeneity remains; Fe is reduced back to a ferromagnetic metallic state and the full interfacial magnetization is regained.

引用

页数：3

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