Ultrasensitive Magnetic Tunneling Junction Sensor
Overview
The sensitivity of current magnetic sensors is often inadequate. Our novel technology incorporates an on-chip magnetic flux concentrator (onMFC) and an external magnetic flux concentrator (exMFC) on a magnetic tunneling junction sensor placed on a silicon wafer. These double-staged MFCs have an amplification factor of 517.
Market Opportunity
Magnetic tunneling junctions, which allow for smaller, thinner, faster, and more cost-effective devices, have many potential uses, including memory devices and analog-to-digital conversion. But most currently available magnetic sensors are insufficiently sensitive. An ultrasensitive magnetic tunneling junction sensor would allow for development of a broad range of high-performing devices.
Innovation and Meaningful Advantages
Our magnetic tunneling junction includes a free ferromagnetic layer of material and a pinned ferromagnetic layer of material. The free and pinned layers are separated by a thin insulating layer of material, through which electrons can tunnel, and an oxidized silicon wafer. The free ferromagnetic layer, insulating layer, and pinned ferromagnetic layer are deposited on the oxidized silicon wafer, and extrinsic magnetic flux concentrators amplify external magnetic fields. The double-staged magnetic flux concentrators enhance the magnetic field sensitivity of the magnetic tunneling junction sensors to an unprecedented level. The two ferromagnetic electrodes are designed to have different responses to magnetic fields so the relative orientation of their moments can be varied with an external magnetic field.
Collaboration Opportunity
We are interested in exploring 1) startup opportunities with investors; 2) research collaborations with leading companies to develop this technology; and 3) licensing opportunities with companies.
Principal Investigator
Gang Xaio, PhD
Professor of Physics
Professor of Engineering
Brown University
gang_xiao@brown.edu
https://vivo.brown.edu/display/gxiao
IP Information
2021-04-08 US10983182B2; Issued.
Brown Tech ID #2577
Publication
Egelhoff WF Jr, Höink VE, Lau JW, Shen WF, Schrag BD, Xaio G. Magnetic tunnel junctions with large tunneling magnetoresistance and small saturation fields. Journal of Applied Physics 2010;107;09C705 2010. doi.org/10.1063/1.3358609.