Conference Paper

Characterization of a quarts MEMS tilt sensor with 0.001º precision

Grad. Sch. of IPS, Waseda Univ., Kitakyushu, Japan
DOI: 10.1109/SENSOR.2009.5285503 Conference: Solid-State Sensors, Actuators and Microsystems Conference, 2009. TRANSDUCERS 2009. International
Source: IEEE Xplore

ABSTRACT This paper presents the performance of recently developed MEMS capacitive tilt sensor. The capacitive sensor, which can be considered as a static accelerometer, is fabricated using bulk micromachining technique on a 100-mum-thick z-cut quartz wafer. High-sensitivity and low-noise are achieved with stable output performance in the range of plusmn1deg. The performance evaluation was performed at the 0.625 V excitation voltage and 9.1 Hz data update rate. The typical sensitivity with good linearity is 403.5 fF/deg, which corresponds to 23.1 pF/g and the typical RMS noise is 74 aF, which corresponds to 25 aF/radic(Hz) (0.9 mug/radic(Hz)) noise floor. High-precision measurement of 0.001deg has been demonstrated.

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