Design and fabrication of high-performance polysilicon vibrating ring gyroscope

This paper presents a detailed analysis on the design and scaling limits of vibrating ring gyroscopes and their implementation using a combined bulk and surface micromachining technology. A high aspect-ratio p++/polysilicon trench-refill fabrication technology has been used to realize the 30-40 /spl mu/m thick polysilicon ring structure with 0.9 /spl mu/m ring-to-electrode gap-spacing. The theoretical analysis of the ring gyroscope shows that by taking advantage of the high quality factor of polysilicon, sub-micron ring-to-electrode gap spacing, high aspect ratio polysilicon ring structure produced using deep dry-etching, and the all-silicon feature of this technology, tactical grade vibrating ring gyroscopes with random walk as small as 0.05 deg//spl radic/h can be realized, providing several orders of magnitude improvement in performance.

[1]  M. W. Putty A Maicromachined vibrating ring gyroscope , 1994 .

[2]  V. Vorperian,et al.  Silicon Bulk Micromachined Vibratory Gyroscope , 1996 .

[3]  Harold A. Rothbart Mechanical design handbook , 1996 .

[4]  Jonathan J. Bernstein,et al.  Micromachining inertial instruments , 1996, Photonics West - Micro and Nano Fabricated Electromechanical and Optical Components.

[5]  Barry Goldstein,et al.  Silicon bulk micromachined vibratory gyroscope for microspacecraft , 1996, Optics & Photonics.

[6]  J. Marek,et al.  A precision yaw rate sensor in silicon micromachining , 1997 .

[7]  K. Park,et al.  Laterally oscillated and force-balanced micro vibratory rate gyroscope supported by fish hook shape springs , 1997, Proceedings IEEE The Tenth Annual International Workshop on Micro Electro Mechanical Systems. An Investigation of Micro Structures, Sensors, Actuators, Machines and Robots.

[8]  W. Higdon,et al.  A CMOS integrated surface micromachined angular rate sensor: its automotive applications , 1997, Proceedings of International Solid State Sensors and Actuators Conference (Transducers '97).