Abstract
This study designs and implements a silicon-based 3-axis Lorentz-force resonant magnetic sensor with single proof-mass using TSMC bulk MEMS above standard CMOS process [1]. The device is a 3-axis resonant-type sensor driven by single current loop. When the magnetic fields applied, the Lorentz-force is induced by current-carrying spring-mass structure and driven the structure at resonant frequency. Capacitance sensing electrodes could detect the dynamic responses of spring-mass system to determine the intensity of magnetic fields. Features of this study: (1) novel spring design acts as current-carrying and enables torsional/in-plane translational motions by magnetic fields; (2) single proof-mass and current loop for 3-axis magnetic fields detection; (3) fully compatible with MEMS inertial sensors process platform. A 1mm - 1mm single proof-mass structure with gap-closing sensing electrodes for 3-axis magnetic fields detection is demonstrated.