本論文之研究旨在藉由不同脈衝之準分子雷射（KrF laser；波長為248 nm）燒蝕製程與熱氫氧化鉀（KOH）化學濕式蝕刻製程，於薄膜（thin-film, TF）覆晶（flip-chip, FC）氮化銦鎵-基（InGaN-based）發光二極體（light-emitting diode, LED）之表面，製備不同尺寸之半球圓弧狀突起物並附加六角錐形狀之表面粗化形貌，以增進LED之光輸出效率與功率。主要研究內容概分為以下四個部分。
第一部分目標係製備薄膜覆晶氮化銦鎵-基發光二極體（TFFC-LED），首先使用有機金屬化學氣相沉積法於圖案化藍寶石基板上製備LED磊晶，接續進行金屬化製程及晶圓接合，並使用KrF laser進行雷射剝離製程以剝離藍寶石基板，最後再藉由乾蝕刻製程定義LED磊晶尺寸（1×1 mm2），成功製備TFFC-LED元件。
第二部分目標係利用不同脈衝數之KrF laser於TFFC-LED之u-GaN表面進行燒蝕製程，利用瞬間高溫使u-GaN表面分解成液態金屬鎵以及氮氣，因GaN磊晶缺陷程度與晶格品質差異造成雷射燒蝕速率不一，於u-GaN上形成半球圓弧狀突起物，接續進行熱KOH濕蝕刻製程，製備具半球圓弧狀突起物，亦附加六角錐形狀之表面形貌。藉由上述製程分別提升GaN磊晶與空氣間之光逃逸角，提升光輸出功率（light output power, LOP）以及提升最大輸出功率（Pmax）。
第三部分目標係量測具不同粗化製程條件之TFFC-LED之發光特性，操作於工作電流350 mA（700 mA）條件下，相較於原始未進行任何粗化製程之TFFC-LED，具150脈衝數之KrF laser燒蝕製程及熱KOH化學蝕刻製程之TFFC-LED，光輸出功率（∆LOP/LOP）提升13.08% （12.81%），以及光電轉換效率（wall-plug efficiency, WPE）增加2.87% （2.25%），上述實驗結果驗證本研究之表面粗化結構有效提升TFFC-LED之光析出效率，亦使TFFC-LED元件於未來固態照明元件之應用上將極具潛力。
第四部分目標係量測具不同粗化製程條件之TFFC-LED之光伏特性，太陽光源為AM1.5G條件，分別以1個太陽能量照射下（光強度：0.1 W/cm2），相較於原始未進行任何粗化製程之TFFC-LED，具150脈衝數之KrF laser燒蝕製程及熱KOH化學蝕刻製程之TFFC-LED，其最大輸出功率（∆Pmax/Pmax）可提升12.87%。另以最佳抗反射結果進行聚光I-V量測，在100個聚光太陽時轉換效率(efficiency, η)為2.06%，相較於相同元件之1個太陽照射時η為1.453%，其轉換效率（∆η/η）增加41.77%。由實驗結果證實本研究所提表面粗化結構確實有效改善TFFC-LED抗反射效果以及適用於InGaN-基太陽電池於高聚光太陽電池之應用。
且預期本研究之雷射粗化製程於GaN-基LED與太陽電池應用上將極具潛力。本研究使用KrF準分子雷射技術表面粗化製程與黃光微影及奈米球微影術等方法相較簡單且不需昂貴設備、冗長複雜的製程步驟及真空製程環境限制等優點，可分別提升GaN-基LED與太陽電池之發光與轉換效率，極具商業應用價值，可作為光電產業製程技術參考。

In this study, an efficient, fast and simple surface texturing process using KrF laser irradiation in conjunction with hot KOH chemical wet etching on the undoped GaN (u-GaN) surface of TFFC-LEDs with a CuW-bonded substrate is demonstrated. The surface roughening scheme that comprises of dome and curved ramp of circular protrusions superimposed by hexagonal cones could be defined a three-fold roughening surface. The proposed surface roughening scheme could effectively improve total internal reflection (TIR) at the u-GaN/air interface. The effects of surface morphology after roughening processes with various numbers of KrF laser irradiation pulses on the performance of TFFC-LEDs are examined by ray-tracing simulations and experiments. As compared to regular-TFFC-LEDs without any etching process, the proposed TFFC-LEDs with 150-pulses of KrF laser irradiation and chemical wet etching (referred to as Device C-150) shows a typical increase in light output power (∆LOP/LOP) of LED by 13.08% at 350 mA. And the proposed Device C-150 shows a typical increase in maximum output power (∆Pmax/ Pmax) of solar cell by 12.87% under 1-sun air mass 1.5 global (AM1.5G) solar illumination. Under 100-sun AM 1.5G, Device C-150 exhibited best energy conversion efficiency of solar cell (η) with 2.06%. The enhancement of Device C-150 in η (∆η/η) was increased with 41.77% under 100-sun AM 1.5G, as compared to the same device under 1-sun AM 1.5G.

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