High Performance MgO-barrier Magnetic Tunnel Junctions for Flexible and Wearable Spintronic Applications.
The magnetic tunnel junction (MTJ) using MgO barrier is one of most important building blocks for spintronic devices and has been widely utilized as miniaturized magentic sensors. It could play an important role in wearable medical devices if they can be fabricated on flexible substrates. The required stringent fabrication processes to obtain high quality MgO-barrier MTJs, however, limit its integration with flexible electronics devices. In this work, we have developed a method to fabricate high-performance MgO-barrier MTJs directly onto ultrathin flexible silicon membrane with a thickness of 14 μm and then transfer-and-bond to plastic substrates. Remarkably, such flexible MTJs are fully functional, exhibiting a TMR ratio as high as 190% under bending radii as small as 5 mm. The devices' robustness is manifested by its retained excellent performance and unaltered TMR ratio after over 1000 bending cycles. The demonstrated flexible MgO-barrier MTJs opens the door to integrating high-performance spintronic devices in flexible and wearable electronics devices for a plethora of biomedical sensing applications.
Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, USA.
Jun-Yang
JY
Chen
School of Physics and CRANN, Trinity College, Dublin 2, Ireland.
Yong-Chang
YC
Lau
School of Physics and CRANN, Trinity College, Dublin 2, Ireland.
J M D
JM
Coey
Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, USA.
Mo
M
Li
Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, USA.
Jian-Ping
JP
Wang