Performance comparison of integrated z-axis frame microgyroscopes

This paper describes two different integrated surface-micromachined z-axis frame gyros fabricated side by side on a single chip for performance comparison. Frame microgyros; using an 'Inside Sense Outside Drive (ISOD)' and an 'Inside Drive Outside Sense (IDOS)' suspension designs were fabricated in the Analog Devices Modular-MEMS process using 6 /spl mu/m thick polysilicon as the structural material co-fabricated with a 0.8 /spl mu/m CMOS process. Initial characterization of these gyros suggest the ISOD frame gyro has a factor of three lower quadrature and Coriolis offset and a factor of five lower noise floor (limited by electronic noise) in comparison with the IDOS frame gyro. The surface-micromachined z-axis ISOD frame gyro exhibited a noise floor of 0.01/spl deg//s//spl radic/Hz and a scale factor of 1.5 mV//spl deg//s at 70 milli-Torr pressure.

[1]  Yong-Kweon Kim,et al.  A few deg/hr resolvable low noise lateral microgyroscope , 2002, Technical Digest. MEMS 2002 IEEE International Conference. Fifteenth IEEE International Conference on Micro Electro Mechanical Systems (Cat. No.02CH37266).

[2]  J. Frech,et al.  Decoupled microgyros and the design principle DAVED , 2001, Technical Digest. MEMS 2001. 14th IEEE International Conference on Micro Electro Mechanical Systems (Cat. No.01CH37090).

[3]  J. Yasaitis,et al.  Integrated surface-micromachined z-axis frame microgyroscope , 2002, Digest. International Electron Devices Meeting,.

[4]  Roger T. Howe,et al.  A modular process for integrating thick polysilicon MEMS devices with sub-micron CMOS , 2003, SPIE MOEMS-MEMS.

[5]  Shinji Kobayashi,et al.  Double-frame silicon gyroscope packaged under low pressure by wafer bonding (特集 振動型センサ・アクチュエータ) , 2000 .

[6]  Y. Mochida,et al.  A micromachined vibrating rate gyroscope with independent beams for the drive and detection modes , 2000 .