應用於無線通訊系統中之被動元件(包括電阻、電容及電感)需具有高品質因子( quality factor )與低損耗的特性，本論文致力於開發一種具高品質因子及寬調變範圍的微型可變電容，主要使用的技術為面型微加工製程技術。

有別於傳統平行板可變電容之低調變率（< 50 %），本研究採用一種具雙間距高度之凹型電極結構設計以及具高彈性係數的新式井型電極佈局設計，並適當降低上電極薄膜之厚度，可將其電容調變範圍提高至65~2100 %。另一方面，為了有效提升元件之品質因子，本論文採用康寧7740玻璃取代矽基板，利用其高阻值之特性以降低高頻訊號之損耗。經網路分析儀於2.4 GHz之操作頻率下，所量測之最佳化元件品質因子為41。

本論文所採用的犧牲層材料為鋁金屬而上電極材料為金薄膜，在微型可變電容結構釋放時，為了避免兩側的支撐壁斷裂致使元件良率降低，本研究採取局部增加上電極兩側支撐壁薄膜厚度的解決方式，同時維持上電極懸浮部位之薄膜厚度，以免造成電容調變率降低與驅動電壓上升。

The passive devices used in the wireless communication system （including resistor, capacitor and inductor）usually need high quality factor and low power dissipation characteristics. This thesis aims to develop a micro tunable capacitor with high-quality-factor and wide-tuning-range using surface micromachining.

In contrast with conventional low-tuning-rate parallel-plate tunable capacitors, this research presents a concave structure and eight-suspending-beams layout design of the top electrode to enhance the elastic rigidity and tuning rate. In addition, this study appropriately decreases the thickness of top electrode, the tuning rate of such device can be improved to 65~2100%. On the other hand, in order to substantially increase quality factor, this thesis adopted the glass substrate （Corning 7740）to reduce the power dissipation of high frequency operating signal. The optimized quality factor of this work is approximately equal to 41 under 2.4 GHz operation frequency.

The material of sacrificial layer and top electrode adopted in this dissertation is aluminum and gold respectively. To avoid any breakage of the vertical supporting beams during releasing process, this research appropriately increases the width of vertical supporting beams, however, keep the thickness of the suspending part of top electrode for the maintenance of high quality factor and low driving voltage.

中文摘要 I
Abstract II
致謝 III
論文目錄 IV
圖目錄 VI
表目錄 X
第一章 緒論 1
1.1 前言 1
1.2 文獻回顧 3
1.3 研究動機 8
第二章 理論介紹 10
2.1 可變電容操作原理 10
2.2 傳統平行板式可變電容器調變原理 11
2.3 新式微型可變電容器調變原理 15
第三章 微型可變電容器設計與製程流程 18
3.1 微型可變電容結構與光罩設計 18
3.1.1 微型可變電容結構設計 18
3.1.2 微型可變電容光罩設計規格與佈局 20
3.2 微型可變電容器製作流程與參數 30
3.2.1 第一代微型可變電容器製作流程與參數 30
3.2.2 第二代微型可變電容器製作流程與參數 41
3.2.3 第三代微型可變電容器製作流程與參數 47
3.3 實驗設備與規格 49
3.3.1 南區國家奈米元件實驗室設備 49
3.3.2 中山大學奈米微系統實驗室設備 52
第四章 微型可變電容器特性量測與分析 57
4.1 第一代微型可變電容器特性量測與分析 57
4.2 第二代微型可變電容器特性量測與分析 61
4.3 第三代微型可變電容器特性量測與分析 65
第五章 結論與建議 70
5.1 結論 70
5.2 建議 72
參考文獻 73

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