Full-Bridge Vortex-Type Tunneling Magnetoresistive Sensor on a Single Die

In order to form a full Wheatstone bridge configuration with linear and bipolar voltage output, a conventional tunneling magnetoresistive (TMR) sensor requires two identical sensing elements that are assembled anti-parallel to each other. Mechanical assembly of two dies induces unavoidable angular errors and a complicated packaging process. Here, we report a full-bridge TMR sensor configured on a single die, which is realized by manipulating the vortex magnetic domain size of the free layer in the magnetic tunnel junctions (MTJs) with different diameters. The sensitivity and linear range of the TMR sensor can be adjusted by changing the vortex size of different bridge arms, which also shows excellent anti-interference performance after a high disturbing magnetic field of 100 mT.