使用混合式（電容式/壓阻式）感測機制的微加速計

Micro Accelerometers with a Hybrid Piezoresistive/Capacitive Sensing Mechanism

傅至璋(Chih-Chang Fu)

指導教授 ： 蔡睿哲

國立臺灣大學/電機資訊學院/光電工程學研究所/碩士(2008年)

https://doi.org/10.6342/NTU.2008.10482

摘要

在本篇論文中,我們將介紹具有兩種感測機制(電容式/壓阻式)的微加速計。 一般說來,微加速計通常只具有單一的感測機制。
在本篇論文中,就我們的所知,我們是第一個將兩種不同的感測機制(電容式/壓阻式)結合在一個加速計上的。
對於我們所設計的平面式移動之加速計而言,在690g的加速度下,所感測到最大電容的改變量為0.028 pF, 在612g的加速度下,壓阻式所感測到的最大電壓變化為0.335V,所感測到的機械結構共振頻率為4.26 kHz,和我們用ANSYS軟體模擬的結果相比之下只有不到5%的誤差。
對於另一個Z軸方向的微加速計而言,在11g的加速度下壓阻式所感測到的最大電壓變化為0.215 V,在10.3 g的加速度下,電容式感測到最大的電容變化為0.26 pF, 機械的共振頻率經由計算為353 Hz。

關鍵字

微加速計

並列摘要

In this paper, we want to introduce a novel micro accelerometer with a hybrid piezoresistive/capacitive sensing technique. In general, micro accelerometer has only one type sensing technique.
In this paper, we report, to the best of our knowledge, the first micro accelerometer using a hybrid capacitive/piezoresistive sensing technique. Here, we will introduce two micro accelerometer, in-plane and out-of-plane, designed by us.
For our novel high-g in-plane micro accelerometer, the measured capacitance change in the capacitive sensing mode is 0.028 pF under 690 g. The measured voltage change in the piezoresistive sensing mode is 0.335 V under 612 g. The mechanical resonant frequency of the micro accelerometer is measured to be 4.26 kHz, i.e. < 5% deviation from the ANSYS prediction.
For our z-axis out-of-plane, the maximum measured voltage change in the piezoresistive sensing mode is 0.215V under 11 g. The maximum measured capacitance change in the capacitive sensing mode is 0.26 pF under 10.3 g. The mechanical resonant frequency of the micro accelerometer is calculated to be 353 Hz.

並列關鍵字

Microaccelerometer

參考文獻

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