A Non Vacuum Packaged Silicon Micro Gyroscope

This paper presents the design, fabrication, and testing of a 50µ m-thick, 5x5mm silicon bulk micro machined non-vacuum packaged gyroscope. The laterally moving vibratory gyroscope is mechanically decoupled in driving and sensing modes with a small damping coefficient. The gyroscope was fabricated by single step of deep RIE process for the silicon-glass bonded wafer. The gyroscope was measured the capacitance change with 81kHz carrier signals and modulated twice by the carrier and driving signals to reduce the driving noises and the parasitic capacitances. A dynamic range of ±200deg/s with nonlinearity less than 0.5% was measured under atmospheric pressure. The resolution with a quality factor of 1260 was measured to 0.011deg/sec by PCB based op-amps circuitry.