[18p-PB2-1~7] 13.4 Si wafer processing /Si based thin film /Interconnect technology/ MEMS/ Integration technology

△ [18p-PB2-2] A Study on 3-axis Fully-Differential Au-Proof-Mass MEMS Accelerometer with Segmented Capacitance Detection Method

〇Shota Otobe¹, Yamane Daisuke¹, Konishi Toshifumi², Safu Teruaki², Iida Shin-ichi², Ito Hiroyuki¹, Ishihara noboru¹, Machida Katsuyuki¹, Masu Kazuya¹ (1.Tokyo Institute of Technology, 2.NTT AT)

Keywords:MEMS accelerometer, Fully-differential, SCD

Microelectromechanical systems (MEMS) accelerometers with the resolution below 1 mG (G = 9.8 m/s^₂) can be used for various applications such as space, human motion monitoring, inertial navigation, and so on. MEMS accelerometer noise is dominated by Brownian noise, which is inversely proportional to the mass. We have developed a single Au proof-mass MEMS accelerometer fabricated by multi-layer metal technology. High-density of gold can reduce the noise when compared to conventional materials, such as silicon. For tri-axis design, we have reported segmented capacitance detection (SCD) for high resolution Au proof-mass MEMS accelerometers. The SCD can be realized by the segmented electrodes (SE) which simplify the MEMS device structure. In this work, we propose a tri-axis fully-differential electrodes structure MEMS accelerometer with SCD for sub-1mG resolution.