B3.4 - Practical Tunneling Magnetoresistive Z-Axis Sensors
- AMA Conferences 2015
2015-05-19 - 2015-05-21
- Proceedings SENSOR 2015
- B3 - Magnetoresistive Sensors
- J. Deak - MultiDimension Technology Co. Ltd., Zhangjiagang (China)
- 245 - 250
A practical tunneling magnetoresistive magnetic field sensor for detecting the magnetic field component perpendicular to the plane of the sensor substrate (Z-axis) is described. The sensor consists of MgO-based MTJs (magnetic tunnel junctions) interconnected as a full-bridge and combined with an array of on-chip flux concentrators. The flux concentrator array is designed to steer the flux from the vertical direction into the in-plane direction parallel to the surface of the substrate enabling the MTJ full-bridge to exhibit true push-pull operation, while additionally providing a high packing density of MTJ elements, which enables robust and high precision performance. The resulting single-chip sensors can be tuned for high sensitivity exceeding 3 mV/V/G or wide dynamic range exceeding 1000 G.