GaN材料本身在藍光及紫外光發光元件上有很大的發展空間。但由於氮化鎵晶體與成長基板的晶格常數不匹配，以及外部量子效率的不佳，使得GaN材料發展受到限制。雖然利用低溫成長的氮化鎵或氮化鋁緩衝層可以改善氮化鎵磊晶層的結晶品質，但還是有109-1010 cm-2 的穿透差排密度存在於磊晶層裡。本文成功地利用奈米球微影術(Nanosphere lithography)製作出奈米圖形化藍寶石基板，並將氮化鎵藍光發光二極體結構成長於奈米圖形化藍寶石基板上，深入地分析此具有奈米圖形化藍寶石基板的藍光發光二極體 ( Light Emitting Diode Grown on Nano-Patterned Sapphire Substrate, Nano-PSS-LED ) 與傳統平面基板和傳統微米等級之圖形化基板發光二極體之差異。
在基板製備方面，使用旋轉塗佈法將直徑500奈米的奈米球均勻塗佈在藍寶石基板上，接著利用電感耦合式電漿蝕刻製程來製作奈米圖形化藍寶石基板，在不同的蝕刻條件下得到不同圖形化的藍寶石基板，並且以有機金屬化學氣相沉積法來成長有圖形化及傳統平面基板之藍光發光二極體。藉由改善磊晶品質與奈米圖形化基板所散射的光，可使藍光發光二極體的輸出功率較傳統平面基板和傳統微米等級之圖形化基板來得高。以奈米圖型化基板所成長的發光二極體與傳統平面基板的發光二極體相較之下，光輸出功率依序有著18%~26%之提升，而利用奈米球微影術製備奈米圖案化藍寶石基板，不但符合可大量生產的條件外，也減少了製程所需之成本與時間，同時也有效地提升了發光二極體之光萃取率，使得發光二極體有更好的光電特性表現。

GaN material have the very big development space on the part in the blue and the ultraviolet LEDs. But because the lattice constant mismatch between GaN and sapphire substrates, and external quantum efficiency is not good. Causes the GaN material development to be restricted. Although the introduction of low temperature GaN or AlN buffer layer can significantly improve the crystal quality of the GaN epitaxial layer. The threading dislocation density has been reported to be of the order of 109-1010 cm-2 in the GaN epitaxial layer. This article successfully uses nanosphere lithography to manufacture nano-patterned sapphire substrates. And grows the GaN blue LED structure on nano-PSS. Analyse the difference between GaN epilayers grown on the nano-PSS, micro-PSS and flat sapphire.
In substrates preparation, using spin coater to coating nanosphere on the sapphire substrate and the nanosphere size is 500nm in diameter. Then, using inductively coupled plasma etched the sapphire substrate. The growth of PSS and flat sapphire blue LEDs were carried out using a MOCVD system. The increase in the output power of nano-PSS was achieved by improving the crystal quality and scattering emission light from the nano-pattern than micro-PSS and flat sphhhire. Compared with nano-PSS LED and conventional LED. There is a 18%~26% improvement in light output power. Manufactures nano-PSS using nanosphere lithography not only suits the commercialize production, but also reduced cost and time in the process.

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