A Novel Z-Axis Capacitance Accelerometer with Highly Symmetrical 16-Beam Structure

Abstract:

A novel highly symmetrical 16-beam sandwich structure Z-axis differential capacitance accelerometer is presented. In this design, the proof mass is suspended symmetrically by double-side of 16 straight beams with highly uniform dimension which can reduce the cross-axis sensitivity and rotational influences dramatically. Parameters of the beam-mass structure were analyzed and optimized by finite element analysis (FEA) software. The micro accelerometer is based on bulk-micromachining by DRIE and KOH anisotropic wet etching technologies. The beam-mass structure was released by anisotropic wet etching on both device layer sides simultaneously. The fabricated accelerometer was measured over the maximum range of 30g gravity field, results of measurement show that the close-loop sensitivity is 80mV/g, the nonlinearity is 0.27%, and the bias stability is 0.63mg for an hour.

• Periodical: Key Engineering Materials (Volumes 562-565)
• Pages: 412-416
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.562-565.412
• Online since: July 2013
• Authors: Wei Li, Lu Feng Che, Xiao Lin Li, Jian Wu, Yue Lin Wang
• Keywords: Capacitance Accelerometer, Highly Symmetric, MEMS, Z-Axis

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