漸變折射層於氮化鎵發光二極體可行性之評估

Evaluating the feasibility of applying graded-refractive-index layers in GaN light-emitting diodes

趙思涵(Ssu-Han Chao)

指導教授 ： 許世杰

淡江大學/工學院/化學工程與材料工程學系碩士班/碩士(2014年)

https://doi.org/10.6846/TKU.2014.00784

摘要

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。

關鍵字

發光二極體 ； 漸變折射層

並列摘要

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.

並列關鍵字

Light Emitting Diode ； Graded Refractive Index ； Light Extraction Efficiency

參考文獻

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