臺灣博碩士論文加值系統

氮化鎵發光二極體(Light-Emitting Diodes，LEDs)具有發光效率高、使用壽命長、環保、省電等優點，為照明設備開啟新的時代。其外部量子效率（EQE）是由光取出效率與內部量子效率所決定，本論文將著重於光取出效率的提升。我們利用光學模擬軟體ASAP (Advanced Systems Analysis Program)建立氮化鎵LED模型，並以蒙地卡羅光線追跡法模擬LED的出光路徑。
為了能夠有效的提升InGaN LED的光取出效率，我們模擬三種結構的LED，三種結構分別為Si基板、藍寶石基板以及垂直式LED，其中垂直式LED是將n-GaN做在上面，p-GaN做在下面的方式來做模擬。另外，我們也在此三種LED加入半球微結構，使整體的光取出效率提高，最後，我們分析此三種LED結構中各層所吸收的光通量。

中文摘要 1
Abstract 2
誌謝 3
目錄 4
圖目錄 6
表目錄 7
第一章 緒論 8
1-1前言 8
1-2 LED的發展 8
1-3 研究動機 10
1-4 論文大鋼 11
第二章 基礎光學理論與LED 發光原理 12
2-1 基礎光學理論 12
2-1-1 反射(Reflection) 12
2-1-2 折射(Refraction) 14
2-1-3 全反射(Total internal reflection) 15
2-1-4 菲涅耳方程式(Fresnel equations) 16
2-1-5 吸收(Absorption) 17
2-2 基礎光度計量學 17
2-2-1 光通量（Luminous flux） 18
2-2-2 發光強度（Luminous intensity） 18
2-3 LED發光原理 20
2-3-1 Lambertian光源 22
2-4 LED發光效率與量子效率 23
2-5 LED光取出效率之提升方式 24
2-5-1 LED表面粗化與微結構 24
2-5-2 改變基板表面形狀 25
2-5-3 使用垂直結構發光二極體 26
2-5-4 改變n-GaN的形狀 26
2-5-5 封裝 27
第三章LED光學模型的建構 28
3-1 光學模擬軟體ASAP 28
3-2 LED光學模型與參數設定 29
3-3 Si基板LED之光學模型 31
3-3-1 Si基板LED之光學模型加入微結構 32
3-4 藍寶石基板LED之光學模型 33
3-4-1 藍寶石基板LED之光學模型加入微結構 35
3-5 垂直式LED之光學模型 36
3-5-1 垂直式LED之光學模型 37
第四章單一微結構光學模擬的結果與討論 38
4-1 單一微結構的結構模擬 38
4-2 光線為中心點出光的模擬 40
4-3 光線為中心點向右側0.2r的地方出光之模擬 41
4-4 光線為中心點向右側0.4r的地方出光之模擬 42
4-5 光線為中心點向右側0.6r的地方出光之模擬 43
4-6 光線為中心點向右側0.8r的地方出光之模擬 44
4-7 討論 45
第五章LED光學模擬的結果 46
5-1 LED之光取出效率 46
5-2 Si基板LED之光取出效率 48
5-2-1 Si基板LED加入微結構之光取出效率 49
5-3 藍寶石基板LED之光取出效率 50
5-3-1 藍寶石基板LED加入微結構之光取出效率 51
5-4 垂直式LED之光取出效率 52
5-4-1 垂直式LED加入微結構之光取出效率 53
5-5光取出效率之比較 54
第六章 LED各層吸收之模擬 55
6-1 LED各層吸收模擬 55
6-2 Si基板LED各層吸收 55
6-3 藍寶石基板LED各層吸收 57
6-4 垂直式LED各層吸收 58
第七章 結論 60
參考文獻 61

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