Magnetic field sensing scheme using CoFeB/MgO/CoFeB tunneling junction with superparamagnetic CoFeB layer

被引：55

作者：

Jang, Youngman

Nam, Chunghee

Kim, J. Y.

Cho, B. K. ^{[1
]}

Cho, Y. J.

Kim, T. W.

机构：

[1] GIST, Ctr Frontier Mat, Kwangju 500712, South Korea

[2] GIST, Dept Mat Sci & Engn, Kwangju 500712, South Korea

[3] Samsung Adv Inst Technol, Mat & Device Lab, Suwon 440600, South Korea

来源：

APPLIED PHYSICS LETTERS | 2006年 / 89卷 / 16期

关键词：

D O I：

10.1063/1.2370876

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

The authors investigated the tunneling magnetoresistance (TMR) of CoFeB/MgO/CoFeB tunnel junctions by varying the thickness (t(CoFeB)) of the top CoFeB layer. Linear and hysteresis-free switching was observed in junctions with t(CoFeB)<= 10 A, while normal tunneling behavior occurred for t(CoFeB)> 10 A. The field sensitivity and the sensing field range were found to be controlled by varying the thickness of the sensing layer. This finding means that the magnetic tunneling junction (MTJ) provides a scheme for magnetic field sensing, which has a simple sensor design and low power consumption. The magnetic properties of the sensing layer with t(CoFeB)<= 10 A were found to show the characteristics of superparamagnetism. Although the detailed mechanism of TMR in MTJs with a superparamagnetic layer is not fully understood at present, this phenomenon is observed repeatedly. Therefore, this sensing scheme would be an alternative method for overcoming the problems in magnetic sensors with a crossed magnetization pattern.

引用

页数：3

共 15 条

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