提升氮化鎵系列發光二極體之發光效率，採用水熱法(hydrothermal method, HTG)成長氧化鋅奈米線(ZnO nanowires, ZnO NWs)，元件表面來達到粗化目的。實驗結果顯示，利用此一技術水平結構LED之光輸出功率(light output power, Lop)於注入電流350 mA下可獲得14.89%之提升。
此外，本研究亦提出整合水熱法成長ZnO NWs與PECVD沈積Si3N4技術，以及利用ICP乾式蝕刻等技術製備Si3N4奈米管(Si3N4 NTs)結構。為了更進一步提升發光效率，本研究利用氧化鋅奈米線當做模板，製備Si3N4奈米管於LED表面來達到粗化的效果，Si3N4奈米管有高達85%的穿透率及獨特的光導性質。我們發現Si3N4奈米管之LED與沒有成長氧化鋅奈米線之LED (regular LED)相比，在350 mA注入下，光輸出功率增加25.23%。

To further improve light output power of LEDs, a cost-effective and efficient surface roughening technology using Hydrothermal Method to grow ZnO nanowires (ZnO NWs) was proposed and demonstrated. Experimental results revealed that the proposed structure could efficiently enhance light extraction efficiency for LEDs. Compared with the regular LEDs, 14.89% in average improvement in the light output power at 350 mA has been obtained from the ones with ZnO NWs.
In addition, through a deposition of thin Si3N4 film to sheathe the hydrothermally grown (HTG) ZnO nanowires arrays (ZnO NW arrays), the high transparent Si3N4 nanotube arrays (Si3N4 NT arrays) were fabricated. The prepared Si3N4 NT arrays with average inner/outer diameters and length of around 350/450 nm and 2 μm, respectively, exhibited a superior transmittance of 85% in visible light spectrum. In addition, surface roughness and light guiding using Si3N4 NT arrays on GaN-based LEDs showed an additional improvement in the light output of about 25.23% at 350 mA as compared to those of regular LEDs, suggesting the effectiveness and promising applications of the proposed Si3N4 NT arrays in optics and optoelectronics devices.

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