Adjusting magnetic nanostructures for high-performance magnetic sensors

Authors

• Xiaolu Yin, University of Nebraska-Lincoln
• Ralph A. Skomski, University of Nebraska-LincolnFollow
• David J. Sellmyer, University of Nebraska-LincolnFollow
• Sy-Hwang Liou, University of Nebraska-LincolnFollow
• Stephen E. Russek, National Institute of Standard and Technology
• Eric R. Evarts, National Institute of Standard and Technology
• John Moreland, National Institute of Standard and Technology
• A S. Edelstein, US Army Research Laboratory
• L Yuan, Western Digital Corporation
• M L. Yan, Western Digital Corporation
• J Shen, Western Digital Corporation

Document Type

Article

Date of this Version

2014

Citation

JOURNAL OF APPLIED PHYSICS 115 (2014)

Abstract

The magnetic properties of the soft ferromagnetic layer in magnetic tunnel junctions are one of key factors to determine the performance of magnetoresistance sensors. We use a three-step orthogonal annealing procedure to modify the nanostructures of the free layer in the magnetic tunnel junction to control features such as magnetization reversal, coercivity, exchange field, and tunnel magnetoresistance ratio. We present a sensor with an improved sensitivity as high as 3944%/mT. This magnetic sensor only dissipates 200 lW of power while operating under an applied voltage of 1V.