為了製作出高效率之白光發光二極體，本研究利用奈米柱陣列結合鋁金屬反射鏡，製成全方向漫射型反射鏡應用於傳統覆晶型藍光發光二極體，並於出光面再成長氧化鋅奈米柱陣列作為一抗反射層，最終以遠端塗佈法塗佈釔鋁石榴石(Y3Al5O12:Ce3+，YAG:Ce3+)黃色螢光粉，製成白光發光二極體。相較於平坦型反射鏡覆晶型白光發光二極體，具有全方向漫射型反射鏡之覆晶型白光發光二極體在相同操作電流下，其光輸出功率可提升由19.95 mW提升至23.91mW，而螢光粉轉換效率則由75.8%提升至80.1 %。此特性改善乃由於全方向漫射型反射鏡可增加背部反射光以及氧化鋅奈米柱陣列作為抗反射層，兩者皆可讓更多藍光激發至黃色螢光粉，使得整體白光提升，故利用全方向漫射型反射鏡結合抗反射層及遠端塗佈技術，可成功實現製作高效率白光發光二極體之目標。

To fabricate high performance white light-emitting diodes (WLEDs), the novel omnidirectional diffused reflectors constructed by depositing the high reflective Al metal on the ZnO nanorod arrays were applied in the conventional nitride-based flip-chip light-emitting-diodes (LEDs). Furthermore, the ZnO nanorods were also grown on the output side of the flip-chip LEDs as the anti-reflection layers. Finally, the yellow phosphor (Y3Al5O12:Ce3+, YAG:Ce3+) layer was coated on the ZnO nanorods anti-reflection layer using the remote phosphor coating technique. Compared with the light output power of 19.95 mW and phosphor conversion efficiency of 75.8% of the nitride -based flip-chip WLEDs with flat reflector, the light output power and phosphor conversion efficiency of the resulting remote WLEDs with diffused reflector operated at the same injection current were improved to 23.91 mW and 80.1%, respectively. The improvement was attributed to the effective back reflection by the omnidirectional diffused reflectors and the ZnO nanorods anti-reflection layer, both of which could guide more blue light to pump the phosphor layer. Consequently, the required white emission was enhanced. The promising diffused reflectors combined with the antireflection layer and remote phosphor coating technique can be applied to realize high performance WLEDs.

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