傳統上，物理方法分為理論和實驗。但隨著電腦運算能力的提升，一種兼具理論與實驗的特性，卻又獨立於外的物理方法，數值模擬，開始蓬勃發展，建立於基本的物理定律，利用電腦模擬在不同情況下之物理現象。本篇研究展示幾種應用於有機薄膜太陽能電池的數值模擬方法。
第一章將介紹有機太陽能電池工作原理與量測技術。第二章與第三章，分別以轉換矩陣法模擬一維層狀結構與以有限時域差分法模擬二三維結構之光學特性。光學模擬能幫助我們在元件製作前設計元件結構且對結構最佳化，或取得一些難以實驗得到的數據，例如光場分佈及激子在有機半導體材料內之擴散長度等。第四章探討元件表現隨入射光強度之變化，並以一簡單的模型對電壓電流量測值做擬合，得到有機太陽能元件中不同再結合機制所佔的比例。第五章以蒙地卡羅法模擬奈米銀線網絡的分佈，評估不同分佈方式對網絡面積覆蓋率及片電阻的影響。最後，總結各章節的模擬結果，並提出未來可能的發展方向。

Physics methods commonly can be catagorized as theories and experiments. However, with the advance of computer calculations, a new method called numerical simulation, which has both characteristics of theories and experiments, becomes more and more popular recently. Based on the basic physical laws, physical phenomenon in different conditions can be simulated by computer programs. In this study, we demonstrate the applications of numerical simulation in optoelectronic properties of the organic thin-film solar cells.
In chapter 1, the operation principles and the characteristics of the organic thin-film solar cells are discussed. In chapter 2 and 3, different optical simulation methods are introduced. The transfer matrix method has been used in 1-D simulations, while the finite-difference time-domain method has been use in 2-D and 3-D simulations of optical characteristics of the organic thin-film solar cells. With the help of simulations, the device structures can be designed and further optimized prior to fabrication. We also show that some physical data, such as optical field distributions in the devices and exciton diffusion lengths in the organic semiconductors, which are difficult to be obtained by real-world measurement, can be extracted. In chapter 4, to explore the dominate recombination mechanism in the organic thin-film solar cells, the J-V characteristics under different illumination intensities have been analyzed and fitted with a simple model. In chapter 5, the Monte Carlo method is applied to the simulation of the silver nanowire network. The effect of the nanowire orientation and distribution on the area coverage ratio and the sheet resistance has been studied. In the last chapter, the results of the simulation in each chapter are summarized and the further development directions are presented.

摘要 I
Abstract II
目錄 III
圖目錄 VII
表目錄 XII
Chapter 1有機太陽能電池原理、量測與光學模擬 1
1-1 簡介 1
1-2 太陽光光譜 2
1-3 有機太陽能電池工作原理 3
1-4 有機太陽能電池光電特性 5
1-4-1 外部量子效率 (external quantum efficiency, EQE)： 5
1-4-2 開路電壓 (open circuit voltage, Voc)： 5
1-4-3 短路電流 (short circuit current, Jsc)： 6
1-4-4 填充因子 (fill factor, FF)： 6
1-4-5 光電轉換效率 (power conversion efficiency, PCE)： 7
1-5 元件結構 8
1-5-1 依有機主動層型態分為： 8
1-5-2 依載子傳輸方向分為： 9
1-6 量測 10
1-6-1 J-V特性曲線量測 10
1-6-2 外部量子效率量測 10
1-7 光學模擬 11
Chapter 2以轉換矩陣法模擬元件內光場分佈 17
2-1 簡介 17
2-2 轉換矩陣法的光學模擬軟體開發 18
2-2-1 轉換矩陣法的光學模擬軟體簡介 18
2-2-2 以轉換矩陣法計算電磁場分佈 18
2-2-3 由Poynting vector計算元件吸收 23
2-2-4 以線性光學修正計算結果 25
2-2-5 由吸收的光子數計算光電流 26
2-2-6 程式介面與模擬結果 29
2-3 應用範例:Single Cell元件膜層厚度最佳化 30
2-3-1 上照光型微共振腔元件 30
2-3-2 高效率及高穿透率雙面透光型元件 30
2-3-3 可調變光色半穿透元件 30
2-4 應用範例:串接型元件膜層厚度最佳化 32
2-4-1 串聯型元件 (series connecions) 32
2-4-2 並聯型元件 (parallel connections) 33
2-5 其餘應用 35
2-5-1 與EQE實驗值擬合得到擴散長度等參數 35
2-5-2 配合變入射光強IV曲線量測重構疊加型元件IV曲線 35
2-5-3 對不同安排方式的元件模擬、最佳化 36
2-6 結論 38
Chapter 3以時域有限差分法模擬元件內光場分佈 74
3-1 簡介 74
3-2 時域有限差分法的基本原理 76
3-3 OptiFDTD模擬 78
3-3-1 OptiFDTD簡介 78
3-3-2 設定Input field 78
3-3-3 材料模型 80
3-3-4 邊界條件設置 81
3-4 具結晶性有機覆蓋層上照光型微共振腔元件 82
3-4-1 元件結構與表現 82
3-4-2 覆蓋層表面形貌 82
3-4-3 FDTD參數設定 83
3-4-4 FDTD模擬結果與討論 84
3-5 結論 85
Chapter 4變入射光強電壓電流曲線量測及分析 102
4-1 簡介 102
4-2 元件表現隨光強變化 104
4-2-1 Jsc對入射光強 104
4-2-2 Voc對入射光強 104
4-2-3 FF對入射光強 105
4-3 DPDCPB、DPDCTB、DTDCPB、DTDCTB 108
4-4 DBP (dibenzotetraphenylperiflanthene) 109
4-5 結論 110
Chapter 5奈米銀線分佈、連結性與片電阻模擬 122
5-1 簡介 122
5-2 以蒙地卡羅法模擬奈米銀線分佈及聯結性 123
5-2-1 奈米銀線分佈 123
5-2-2 聯結性計算 124
5-3 奈米銀線片電阻計算 126
5-3-1 節點分析 126
5-3-2 由奈米銀線分佈建立電路 127
5-4 有效覆蓋率對銀線密度變化 131
5-5 片電阻對銀線密度變化 132
5-6 與實驗結果比較 133
5-6-1 銀線密度估算 133
5-6-2 片電阻比較 134
5-7 結論 135
Chapter 6結論與未來展望 150
參考文獻 151

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