在白光發光二極體照明的應用上，受限於氮化鎵晶粒的發光效率與螢光粉的轉換效率，目前白光二極體發光效率只有74 lm/W，尚不足以取代日常照明。為了提高發光亮度以及改善效率，在本論文中分別以大面積元件及覆晶式元件製程技術為研究之目標；應用大面積元件之技術可增加元件的操作電流，達到光能輸出增加的效果。同時為了增進元件在高操作電流下的效率表現，大面積發光二極體若配合覆晶之製程技術則可增加熱散逸的能力，減緩因熱累積而造成的效率下降。在本論文中主要針對發光二極體尺寸大型化時出現之電流擁塞現象及覆晶式元件反射電極之熱穩定性做研究探討，並提出改善之方案。最後結合上述兩項技術所製作的大面積覆晶式氮化鎵發光二極體，能達到提高光能輸出，同時維持元件操作時穩定性的目標。

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國立中央大學電機所碩士論文