隨著智慧車輛的發展，各式車用感測器的需求大增，而其中光學雷達(Light Detection and Ranging, LiDAR)比起傳統車用雷達可更快速感測周遭的人、物，讓駕駛做更即時的反應。微掃描面鏡在光學雷達系統中可作為入射光之掃描工具，而優值(Figure of Merit, FoM)為評鑑微掃描面鏡的重要指標，於光學雷達的應用上較高的優值可有較好的性能。
本研究主要利用PZT壓電薄膜搭配SOI晶圓之製程平台進行壓電式單軸微掃描面鏡的製作與實現，並藉由扭轉軸的設計提升微掃描面鏡的光學雷達性能。完成後首先萃取各項PZT參數，而後進行元件之光學量測。結果顯示具有扭轉軸結構之微面鏡於5 VPP電壓之共振頻(4.57 kHz)狀態下，可有7.33°之掃描角，相比於無扭轉軸之純致動彈簧結構微面鏡，能在相同操作電壓下，提升12%的FoM，亦即可有較好之光達性能；與此同時，可有將扭轉模態與出平面模態之共振頻差距拉開之效果，以此可減低模態耦合發生之可能性。

With the development of smart cars, the demand for various automotive sensors has increased. Among them, Light Detection and Ranging (LiDAR) which is also known as the eyes of the car can sense faster than traditional automotive radars. This ability can let drivers react to the surrounding people and objects more instantly. The micro scanning mirror made by MEMS process is used as a scanning tool for incident light. Figure of Merit (FoM) is an important index for evaluating micro scanning mirrors, and higher FoM can have better performance in the application of LiDAR.
This study utilizes PZT platform to implement a novel piezoelectric single-axis micro scanning mirror. By designing a pair of torsional springs at the central of the mirror, FoM can be boosted. By measurement, it can perform 7.33° scanning angle under 5 VPP voltage and 4.57 kHz resonant frequency, which enhances 12% LiDAR performance in contrast with the reference type without torsional springs. Also, material properties of PZT have been well measured in this study to estimate possible operation range. At the same time, the resonant frequency difference between torsional mode and piston has increased by the additional effect of the torsional spring. It could reduce the possibility of mode coupling.

摘要 I
Abstract II
誌謝 III
目錄 VII
圖目錄 X
表目錄 XVII
第一章 緒論 1
1-1 前言 1
1-2 文獻回顧 4
1-2-1 靜電式致動微掃描面鏡 4
1-2-2 電磁式之勞侖茲力致動微掃描面鏡 7
1-2-3 電磁式之靜磁力致動微掃描面鏡 10
1-2-4 壓電式致動微掃描面鏡 11
1-3 研究動機 14
1-4 全文架構 15
第二章 元件致動原理與設計考量 32
2-1 壓電致動機制 33
2-2 設計概念 34
2-2-1 壓電材料選擇 34
2-2-2 元件設計概念與模擬分析 35
2-2-3 鏡面反射層材料之選用 39
第三章 製程結果與討論 54
3-1 製程流程 54
3-1-1 壓電層濕蝕刻 56
3-1-2 鉻金薄膜蒸鍍及上電極掀舉製程 57
3-1-3 正面第一道乾蝕刻製程 60
3-1-4 正面第二道乾蝕刻製程 63
3-1-5 背面熱氧化層蝕刻製程 63
3-1-6 背面深矽蝕刻製程 64
3-2 製程結果 67
第四章 量測結果與討論 83
4-1 PZT材料特性量測 83
4-1-1 d31壓電係數 83
4-1-2 PZT極化率 86
4-1-3 位移-電壓之關係曲線 87
4-2 機械特性量測 89
4-2-1 元件共振頻量測 89
4-2-2 元件表面形貌量測 90
4-2-3 元件模態量測 91
4-3 光學特性量測 92
第五章 結論與未來工作 108
5-1 結論 108
5-2 未來工作 109
5-2-1 膜層厚度之選擇 109
5-2-2 壓電微掃描面鏡之可靠度測試 110
參考文獻 116
附錄A－元件背面製程之改良 124
附錄B－量測鏡面動態變形之方法 132
附錄C－後續製程規劃與調整 136
C-1 硬遮罩之選擇 136
C-2 PZT蝕刻之新方法 137

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