微環形共振腔為矽光學(silicon photonics)中廣泛研究的主題，因具有高度的波長選擇能力，且可透過溫度或者PN參雜的方式來位移共振波長，增加波長選擇的能力。近年來在 SOI的領域上，提出了利用液晶取代波導的包覆層，因液晶具有雙折射特性，透過此特性可達到相當大的波長位移，且調控液晶時所需的能量低，故本論文選定此題目來做一系列的研究。
　　本論文中選用的液晶皆為向列型液晶(Nematic liquid crystal)，而波導的材料為氮化矽(SiN)及矽(Si)，本論文同時也會針對大半徑(40μm)及小半徑(2.5μm)的環性共振腔做模擬計算與實際的實驗。但在過往的研究中，面臨著驅動電壓過大及配向的問題，有鑑於此，本論文設計發表全新的電極結構，一次改善了以上兩個缺點，並提出一系列的模擬計算，且在實際製成出來的測試晶片中，我們的確降低了驅動電壓，並利用波導製造出了凹槽，解決了配向的問題，使液晶雙折射性可以完整地展現出來。
　　液晶是一相當良好的光電轉換媒介，但其反應時間相對於電訊號的世界算是相當的緩慢(大約都落在10ms左右)，所以與微環形共振腔結合應用的元件無法達到高速的切換，主要可應用的領域為濾波器類型的元件。

Micro-ring resonator have been extensively studied in field of silicon photonics, because of its excellent wavelength selectivity. We can tuning wavelength by temperatures or doping PN except these two methods. We serve liquid crystals as a cladding layer and the device exhibit large phase shifts and wide resonance-wavelength tuning by utilizing the birefringence change in the liquid crystal cladding. The liquid crystal layer can be modulated by electrical field, optically control and heater.
　　In this study, we clad the nematic liquid crystal on the silicon nitride waveguide (SiN) and silicon waveguide(Si). Both large radius (40μm) and a small radius (2.5μm) ring resonator are made of simulation and experiment. In the previous researches, the drive voltage is too large and the alignment problem remains. As a result, we demonstrate a new electrode design to improve the above problems and make a series of simulation. In the experiment, we clad the liquid crystal on the test wafer. The result shows that we have actually reduced the drive voltage and create an alignment by waveguide.
　　Liquid crystals exhibit an excellent electro-optical property, but the response time is quite slow relative to the world of telecommunications(about 5-20ms). Therefore, the combination of liquid crystal and micro-ring resonator can not achieve high-speed switching, but we can make it into the a tunable filter.

中文摘要 i
Abstract ii
目錄 iii
圖目錄 vi
表目錄 ix
第一章 緒論 1
1.1. 簡介 1
1.2. 論文概述 2
第二章 波導基本原理 3
2.1. SOI波導 3
2.2. 光學損耗[10] 4
2.2.1散射損耗[11] 4
2.2.2吸收損耗[12] 6
2.2.3輻射損耗 6
2.3. 微環形共振腔 8
2.3.1塞取式濾波器數學形式推導 9
2.3.2波長選擇性 12
2.3.3自由頻譜空間(Free spectral range, FSR) 12
第三章 液晶基本原理與應用 15
3.1. 液晶簡介 15
3.1.1液晶的分類[16] 16
3.2. 液晶的物理特性 17
3.2.1雙折射性 19
3.2.2介電係數異向性[17] 21
3.2.2彈性係數異相性 23
3.3. 液晶折射率之量測 24
3.3.1實驗原理與量測方法 24
3.3.2實驗結果 28
3.4. 液晶的表面效應 30
3.5. 液晶與環型共振腔之結合 31
3.5.1模擬計算 32
第四章 實驗設計與量測 35
4.1. 實驗方法 35
4.1.1材料介紹 36
4.1.2試片準備 37
4.1.3實驗器材架設與方法 41
4.2. 氮化矽波導與邊緣耦合對光 45
4.2.1參數設定 45
4.2.2實驗結果 46
4.2.3分析與探討 49
4.2.4電極位置改良 50
4.3. 矽波導與光柵耦合器 53
4.3.1參數設定 53
4.3.2實驗結果 54
4.3.3分析與探討 55
第五章 新電極設計發表 56
5.1. 實驗回顧與新電極設計 56
5.1.1布局(Layout)參數設計 58
5.1.2模擬計算 60
5.2. 實驗結果 66
5.2.1凹槽配向能力測試 66
5.2.2電極驅動測試 69
第六章 結論 72
參考文獻 73

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