High-performance micromachined gyroscope with a slanted suspension cantilever

This paper presents a novel structure for improving the stability and the mechanical noise of micromachined gyroscopes. Only one slanted cantilever is used for suspension in this gyroscope, so the asymmetry spring and the thermal stress, which most micromachined gyroscopes suffer from, are reduced. In order to reduce the mechanical noise, the proof masses are designed to be much larger than in most micromachined gyroscopes. The gyroscope chip is sealed at 0.001 Pa vacuum. A gyroscope sample and its read-out circuit are fabricated. The scale factor of this gyroscope is measured as 57.6 mV/(deg/sec) with a nonlinearity better than 0.12% in a measurement range of ±100 deg/sec. The short-term bias stability in 20 min is 60 deg/h.