Vacuum packaged low noise gyroscope with sub mdeg/s//spl radic/Hz resolution

摘要

This paper describes a vacuum packaged z-axis gyroscope with sub milli-deg/s//spl radic/Hz noise floor. A design rule for the low noise gyroscope is suggested, and lateral vibrating gyroscope was fabricated through a metal interlaid SiOG technology. High aspect ratio (20:1) silicon structures were fabricated without footing damage. The easy method for the electric connection of feed through holes that are 150 /spl mu/m in diameter is suggested for vacuum package of SiOG structure. The vacuum packaged gyroscope with a quality factor of 10,000 exhibits a noise floor of 0.4 mdeg/s//spl radic/Hz, and a bias stability of 4.7 mdeg/s (=17 deg/hour), where the scale factor is 68.5 mV/deg/s with 0.6% linearity error for the range of 200 deg/s.