Resonant mechanical magnetic sensor in standard CMOS

A novel micromechanical magnetic sensor has been built and tested. The field is detected by measuring the vibration amplitude of a mechanical Lorentz force oscillator. This device is made from a standard 2-μm CMOS fabrication process with a post-processing etch step to undercut and release the sensor. When operated at the resonant frequency of the mechanical system, a sensitivity of 20 μV/G was measured.