Tunneling Magnetoresistance (TMR) Materials and Devices for Magnetic Sensors

With the booming development of consumer electronics products, superior magnetoresistance (MR) sensors gradually substitute traditional sensors based on the Hall effect. Among these MR sensors, tunneling magnetoresistance (TMR) sensors, presenting advantages of high sensitivity, miniaturization, and low power consumption, draw wide concern in both academic and industrial fields, and become a very promising industrial direction recently. Moreover, large amounts of application scenarios based on TMR sensors have been widely proposed and studied. This chapter will focus on the TMR sensors, from the aspects of TMR effect, stack structure, material growth process, patterned technology, device to application area, etc. In particularly, various noise sources in the TMR sensors are analyzed systematically and the commonly used methods of improving signal-to-noise ratio are introduced. The content of this chapter would help readers comprehensively understand the graphic structure of TMR sensors and their device application prospect.