本論文旨提出一具可撓式基板之氮化鎵系列垂直結構發光二極體(Flex-LED)之製造技術，以提升元件於各種軟式電子材料或非平面形狀面板之應用。
為提升元件之電流擴展能力、降低串聯阻值，我們先針對垂直結構發光二極體所需之最佳n-GaN厚度做一理論與實驗性研討。經實驗與理論證明，在載子濃度為1019 cm-3時，n-GaN之最佳化厚度為2.5 m。
一熱穩定的彈性導電膠體被作為晶圓鍵合的介質層，此一彈性膠體係由鍍鎳樹脂球與可撓式聚脂組成，於常溫至200oC的操作範圍內皆具有極佳之彈性緩衝特性。具可撓性之不鏽鋼基板，晶圓鍵合過程在180oC下以15秒完成。經區塊雷射剝離、表面粗化與電極成形，所提之具緩衝外在形變並維持穩定特性600×600μm2之Flex-LEDs是為完成。在注入電流為120 mA時，Flex-LED之順向壓降為3.3 V，光輸出(LOP)值為43 mW；與水平結構相較，順向壓降減少0.21 V，光輸出改善為80%，元件整體光電轉換效率達91%。在元件與外力相依性的量測上，我們定義一基板等效長度(Effective Length , Le)作為所施外力的指標。透過施加外力繞曲元件基板改變其等效長度至5 mm時，其主波長最大位移量為0.3 nm。同時，元件之光輸出與電流電壓特性維持相當的穩定無明顯變動。印證所提之元件結構對於外力的響應極小且具穩定之重現性。

This thesis is aimed to expand the application of GaN-based light-emitting diodes (LEDs) into Flextronics. Through the use of a thermal stable elastic conductive adhesive (ECA), a vertical structure GaN-based LED was fabricated on flexible stainless steel substrates (Flex-LEDs).
Before device fabrications, a theoretical and experimental study on optimal n-GaN thickness for the device fabrication was carried out for the pursuit of least parasitic resistance with good current spreading. Based on our experimental results, the optimal n-GaN thickness is 2.5 m. This thickness was used hereinafter.
The wafer bonding process was carried out at 180oC for 15s. After patterned laser lift-off, u-GaN removal, surface treatment, and electrode formation, Flex-LEDs with a size of 600×600 μm2 were fabricated. It was seen that the forward voltage (VF) and light output power (LOP) of Flex-LED at 120 mA are 3.3 V and 43 mW, respectively. As compared with regular LEDs, VF was 0.21 V less and LOP was 80% enhanced. This resulted in a 91% improvement of power conversion efficiency. The performance stability confronting external stress was further examined through substrate curving. It showed that Flex-LEDs have negligible changes dominant wavelength -current (WD-I) characteristics to bend from a plane length of 24 mm to an effective length of 5 mm. In the meantime, the light output intensity -current-voltage (L-I-V) remained stable without noticeable variations.

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