本論文是利用TracePro光學軟體，模擬漸變折射層(Graded-refractive-index)應用於氮化鎵發光二極體(GaN-Based LED)之封裝製程，驗證其光通量是否具有提升效果。
研究中我們對氮化鎵發光二極體進行多層封裝來製作複合漸變折射層結構以提升其光萃取效率（Light Extraction efficiency）。由模擬結果得知，相較於傳統之單層封裝膠(n=1.4)，具有漸變折射層的封裝結構其光通量最高可以提升8.95%，同時也發現隨著封裝材料的折射率越提高，光通量也會隨之提升。此外，分別模擬不同層數的封裝結構，發現三層和四層的結構其光通量數值相近，由此可知漸變折射層的分層數目和光通量增加量有其極大值。
綜合本研究之模擬結果，可以發現多層漸變折射層複合封裝材料對於改進LED光萃取效率的確有其效果，但應以四層為限度。且最內層和最外層的折射率差值越大越好，尤其是最內層的材料折射率應要在小於氮化鎵材料折射率的情況下儘可能的大，此時效率為最佳。

Utilize TracePro software work in Graded-refractive-index(GRIN) structure for GaN-Based LED encapsulation process. We prove light extraction efficiency related with GRIN.
We use multi-layers encapsulants as Graded-refractive-index(GRIN) structure for LED encapsulants. From simulation results, the light extraction of multi-layers enhance 8.95% than single layer. And also we found encapsulants of refractive index gradually increase, luminous flux will get higher. Besides we find four layers encapsulant structure have maximum value. According to the simulation result, the GRIN layer influence of luminous flux.

目錄
致謝	V
目錄	VI
圖目錄	VIII
表目錄	X
第一章 序論	1
1.1 前言	1
1.2 研究動機與目的	2
1.3 漸變折射層之相關文獻回顧	5
1.4 論文架構	9
第二章 理論基礎與原理
2.1發光二極體概述	10
2.2 發光體之光學性質	12
2.2.1 光通量(Luminous，單位記號：Φ)	12
2.2.2 光強度(Luminous intensity，單位記號：I )	12
2.2.3 照度(Illuminance，單位記號：E )	13
2.2.4 輝度(Luminance，單位記號：L )	13
2.3 發光二極體的效率	14
2.4 發光二極體的封裝材料	18
2.4.1 環氧樹脂	19
2.4.2 矽膠	20
2.4.3 漸變折射層	22
2.4.4 奈米粉體–二氧化鈦 	24
第三章 實驗軟體
3.1 TracePro 光學模擬軟體簡介	26
第四章 結果分析與討論
4.1封裝材料形狀效應結果與分析	27
4.2雙層漸變折射層之結果與分析	31
4.3三層漸變折射層之結果與分析	34
4.4多層漸變折射層之結果與分析	36
第五章 結論與未來工作
5.1 結論	37
5.2 未來工作	38
參考文獻	39
附錄A實驗流程	44
附錄B實驗材料	51


圖目錄
圖1.1 內部全反射示意圖	4
圖1.2 漸變折射層封裝結構示意圖	4
圖1.3 漸變折射層示意圖	7
圖1.4 光萃取效率與封裝材料折射率關係圖	7
圖1.5 摻有奈米粒子的雙層封裝結構	8
圖1.6 摻有奈米粒子並搭配透鏡雙層封裝結構圖	8
圖2.1照明趨勢發展與發光效率	11
圖2.2外部量子效率示意圖	15
圖2.3 SMD封裝	16
圖2.4 TO can	16
圖2.5高功率封裝LED結構圖	17
圖2.6環氧樹脂固化示意圖	20
圖2.7二氧化鈦晶體結構(a) 金紅石(b) 銳鈦礦	24
圖3.1 TracePro光學模擬軟體	26
圖4.1 光學模擬模型	28
圖4.2 偵測器全收光方式示意圖	….29
圖4.3 不同形狀封裝材料全收光之模擬結果	29
圖4.4沒有Fresnel loss之模擬結果	30
圖4.5雙層之模擬結果	32
圖4.6雙層折射率差異過大之模擬結果	33
圖4.7三層之模擬結果	35
圖4.8綜合之模擬結果	36
圖A-1實驗流程圖	45
圖A-2封裝膠材料製備流程圖	47
圖A-3 TiO2 Raman光譜圖	48
圖A-4 SMD5050	49
圖A-5打完金線的藍光晶片	49
圖A-6 實驗用的藍光(447 nm)晶片之光譜圖	50
圖A-7 DowCorning OE-7620	50
圖B-1 光學顯微鏡	51
圖B-2 螺旋測微儀	52
圖B-3 光譜儀	52
圖B-4 L-I-V量測系統	53






表目錄
表1.1 漸變折射層之相關文獻回顧	9
表2.1 DowCorning公司各型號的矽膠產品型號	21
表2.2無機奈米粉體的光學性質	23
表4.1 光學模擬之建模條件	28

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