0.018 /hr, SUB-0.2 /hr MEMS PITCH/ROLL PIEZORESISTIVE GYROSCOPE WITH DECOUPLED TILT OF THE MASS AND OF THE GAUGES LEVER

This work presents a novel single-axis gyroscope for pitch (or roll) rate detection based on an improved stress amplification architecture for the piezoresistive nanogauges of the sense mode. The design decouples the lever tilting angle, responsible of the stress applied onto the gauges, and thus of the scale-factor, from the proof mass tilting angle induced by the Coriolis force: this determines a sensitivity increase and thus the possibility to obtain high-performance pitch rate detection. The sensor is coupled to an integrated circuit which sustains the drive oscillation and reads out the open-loop sense chain. Results show 306 mu dps/vHz angle random walk and 0.12 degrees/hr bias stability, which rank this device among the top performing pitch/roll gyroscopes in the literature, in ultra-small footprint.