本研究目的為利用非均質結構產生之介電泳力去調控聚苯乙烯微球(共振腔)與脊狀波導間的垂直耦合距離，首先利用投影機投影圖形在光導材料(a-Si)上，利用其產生的不均勻電場誘發介電泳力去操控微米球共振腔至波導附近，此時微米球會受到非均質結構(脊狀波導)的吸引力而停在波導的正中心，接著利用改變外加電壓去調整微米球共振腔與單模脊狀波導之間的垂直耦合距離。
在我們的元件中滴入混有聚苯乙烯球(n=1.571)的蔗糖水溶液(n=1.34)，並以SU-8負光阻(n=1.569)製作脊狀波導(非均質結構)於晶片上，經由實驗量測微米球共振腔與光波導間的穿透頻譜，透過分析頻譜上峰值的深度以及透過頻譜擬合計算得到的品質因子，可將在不同操作電壓下聚苯乙烯球與光波導間的耦合情形分別歸類在過耦合(over-coupling)，近臨界耦合(near critical-coupling)，和弱耦合(under-coupling condition)等三種情況。

The main theme of this research is to implement a tunable microsphere resonator platform with an ability of manipulating the coupling distance between a polystyrene microsphere (resonant cavity) and a rib waveguide through a controllable dielectrophoretic (DEP) force on an inhomogeneous structure. The microsphere is suspended in liquid sealed in between two transparent conductive plates. One is coated with amorphous Si and the other is with an SU-8 waveguide structure. First, we use the image-controlled dielectrophoresis for moving the microsphere near the rib waveguide; then, the microsphere will be attracted by the rib and stop in the center of the rib waveguide by a localized DEP on the inhomogeneous structure (rib edge). By changing the applied voltage, the coupling distance between the microsphere and the single-mode rib waveguide is continuously adjustable. Through measuring the waveguide transmittance spectra at different biased voltages across the top and bottom plate, the PSB microsphere is able to be operated either at the over-coupling, near critical-coupling or under-coupling condition. The intrinsic quality factor is estimated to be 26707.

目 錄
摘 要………………………………………………………………………………Ⅰ
Abstract……………………………………………………………………………Ⅱ
致謝……………………………………………………………………………Ⅲ
目 錄…………………………………………………………………………………Ⅳ
圖 目 錄……………………………………………………………………………Ⅵ
表 目 錄…………………………………………………………………………Ⅷ
第一章、緒論 1
1.1前言 1
1.2研究動機與目的 4
1.3論文架構 5
第二章、理論背景 6
2.1球型共振腔模態 6
2.1.1耳語廊模態 6
2.1.2品質因子 8
2.1.3自由光譜範圍 9
2.2光波導理論 10
2.2.1平板波導 10
2.2.2脊狀波導 14
2.2.3單模脊狀波導 16
2.3共振腔與光波導間的耦合 18
2.3.1相位匹配與模場重疊 18
2.3.2耦合因子 18
2.4介電泳原理 21
2.4.1介電泳效應 21
2.4.2馬克斯威爾張量(Maxwell stress tensor) 23
2.4.3光介電泳原理 25
第三章、元件模擬與設計 27
3.1脊狀波導模擬 28
3.1.1單模脊狀波導條件 28
3.2元件光場模擬 30
3.3介電泳模擬 32
3.3.1重力 32
3.3.2 介電泳力 32
3.4元件設計與製程 40
3.4.1元件製作流程 41
3.4.2元件製作流程詳細步驟 42
第四章、實驗量測與分析 46
4.1實驗系統架構 46
4.1.1光介電泳操縱 46
4.1.2光學量測系統 48
4.2光學量測分析 50
4.2.1穿透頻譜自由光譜範圍(FSR) 51
4.2.2穿透頻譜品質因子分析(Q-factor) 53
第五章、實驗結果與討論 57
參 考 文 獻 60

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