本論文主要針對多軸向電容式微加速度計進行設計與製作，首先藉由微機電軟體(CoventorWare)，減少模型建立時間以及快速的進行其模擬結果之驗證，並對微加速度計做結構之最佳化設計。再以國家晶片中心提供與CMOS相容之MEMS製程，並結合犠牲層技術使結構達到懸浮的目的，犠牲層方面乃利用矽當做基底，製作出高深寬比之微加速度計微結構。
本文提出個別三軸加速度感測計，並利用CMOS製程設計感測電路以放大讀取訊號。平面式加速度計採用電容式感測並搭配儀表放大器作為感測電路，其中單軸微加速度計第一自振頻設計在3 kHz以上，靜態下感測電容值為120 fF左右，在受到1 g加速度下電容變化量約為0.7 fF，根據感測電路量測結果可得到其輸出值約為2 mV/g，搭配輸出端混頻器解調，其靈敏度可提升至8 mV/g；雙軸加速度計第一自振頻設計在5 kHz以上，靜態下感測電容值約為80 fF，在受到10 G加速度下電容變化量約為0.2 fF，模擬輸出電壓值得到100 mV；出平面式加速度計採用壓阻式感測並搭配惠司同電橋作為感測電路，採用四端固定端型式增強整體質量塊硬度，壓阻材料採用poly-silicon作為感測薄膜，在考量最大感測度以及製程變異下，設計靜態阻值為195.04 kΩ，在10 G加速度下阻值變化約為5 Ω，透過感測電路放大訊號並給定輸入電壓為5 V，得到輸出電壓模擬結果為0.03 mV。

This thesis is contained multi-axis MEMS capacitive accelerometer. It constructs the 3D model easily and uses the finite element method (FEM) to simulate the mechanical equation by CoventorWare which is MEMS simulation software. It also provides the optimum design of the micro-accelerometer by CoventorWare. In this design, I use CMOS-MEMS 0.35 μm process by TSMC and APM to make the structure suspending through the technology of scarification layer. It will fabricate the high aspect ratio micro accelerometer.
This research mentions three axis sensing accelerometer respectively and uses the CMOS process to design the instrument amplifier for readout circuit. The in-plane accelerometer is designed by capacitance sensing with instrument amplifier. The out-plane accelerometer is designed by piezo-resistive sensing with Wheatstone bridge.
The sensitivity of single-axis accelerometer is 2 mV/g and is risen to 8 mV/g through multiplier to demodulate output signal. The resonant frequency of single-axis accelerometer is 3 kHz. Static capacitance of comb finger is about 120 fF. The sensitivity of dual-axis accelerometer is 0.02 fF/g and resonant frequency is located at 5 kHz. Static capacitance of comb finger is about 80 fF. The sensitivity of Z-axis accelerometer is 0.5 Ω/g and resonant frequency is located at 22 kHz. Static resistance of cantilever is about 195.04 kΩ.

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