A CMOS-MEMS lateral-axis gyroscope

This paper reports on the experimental results from the first design of a CMOS lateral-axis vibratory gyroscope that utilizes comb fingers for both actuation and sensing. The fabrication is compatible with standard CMOS processes and the design has an integrated, fully-differential capacitive interface circuit. This gyroscope design uses integrated comb drives for out-of-plane actuation, and is motivated by the desire to integrate three-axis gyroscopes on a single chip. The packaged gyroscope operates at atmospheric pressure with a sensitivity of 0.12 mV/deg/s and the resonant frequency of the drive mode is thermomechanically tuned between 4.2-5.1 kHz. Resonant frequency matching between the drive and sense modes is realized by integrating a polysilicon heater inside the spring beams.