The Internet of Things has created an increasing demand for giant magnetoresistive (GMR) sensor owing to its high sensitivity, low power-consumption and small size. A full Wheatstone bridge GMR sensor is fabricated on 6-inch wafers with an annealing process on patterned devices. It can be observed that GMR resistors could have different pinning directions in one wafer by magnetic resistance measurements and MATLAB simulations. The full Wheatstone bridge device shows a sensitivity of 2 mV/V/mT in a linear range of ±6 mT, and its angular response to the surrounding magnetic field is as low as 0.08 mT. These results demonstrate a new approach to high-sensitive and low-cost GMR sensors with a controllable post annealing process.

物联网因其高灵敏度，低功耗和小尺寸而对巨型磁阻（GMR）传感器产生了越来越高的需求。完整的惠斯通电桥GMR传感器是在6英寸晶圆上制造的，并在图案化器件上进行了退火处理。通过磁阻测量和MATLAB仿真可以看出，GMR电阻器在一个晶片中的钉扎方向可能不同。完整的惠斯通电桥器件在±6 mT的线性范围内显示2 mV / V / mT的灵敏度，其对周围磁场的角响应低至0.08 mT。这些结果证明了一种具有可控的后退火工艺的高灵敏度，低成本GMR传感器的新方法。