中文摘要

本研究的目標設定在利用微機電技術設計並製造一z軸加速度計，並結合CMOS積體電路製程完成一新穎的z軸CMOS MEMS電容式微加速度計。有別於一般文獻內的CMOS MEMS加速度計多是以xy軸作感測，而比較少有z軸方向的感測，此外我們所需要之後製程只需一次簡單的乾蝕刻(HFVPE)，且不需任何光罩，相對於一般CMOS MEMS z軸加速度計而言後製程是非常簡單的。
現今市場中由於Wii遊戲機的推出，使加速度感測計的需求度大幅上升，相關研究亦十分熱門。因此我們提出製作一新穎、製程簡單且具高感測度之z軸微加速度計，而以製作z軸CMOS MEMS電容式微加速計而言，我們所提的乾蝕刻製程有其獨到的適用性，甚至不亞於Analog Devices的iMEMS 製程，因為在設計上其電極離基板稍遠，可以降低寄生電容值，增加SNR。我們結構的特色為只使用單層金屬薄膜，因此結構的厚度很薄(0.9 μm)，所以我們的彈簧設計可容易達成低彈性係數的目標，且結構電容之間的間距小於1 μm，因此亦容易設計電容值較大的感測電容。而訊號經由感測電路的放大，實驗結果顯示在受到1 g加速度搖晃時能得到5.7 V之感測電壓，因此我們的感測度為5.7 V/g，加速度計之解析度則可達1 ，而在適當的量測環境下應可達到 μg解析度目標。
關鍵字：z軸加速度計、CMOS微積電、電容式感測加速度計。

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