本論文提出數種週期結構來提升氮化鎵發光二極體之出光效率，這些週期結構主要包括了自我複製式光子晶體(auto-cloned photonic crystal, APhC)，與微反射鏡陣列(micro mirror array, MMA)結構，藉由調整這些結構特徵來探討其對發光二極體出光效率(light extraction efficiency)的影響。

　　首先使用以有限時域差分法(finite difference time domain, FDTD)為基礎的FDTD Solution軟體計算自我複製式光子晶體發光二極體(APhC LED)，與內嵌微反射鏡陣列發光二極體(MMA LED)的出光效率，確認這些結構確實可提升出光效率。

　　接著再以嚴格耦合波分析(Rigorous coupled wave analysis, RCWA)軟體配合自行設計的多重反射運算方法來進行發光二極體的出光效率計算，此方法相較於使用FDTD方式來計算出光效率更為省時，因此適合用來對自我複製式光子晶體發光二極體，與內嵌微反射鏡陣列發光二極體進行結構上的優化。

　　由嚴格耦合波分析這些週期結構的繞射特性得知，無論是自我複製式光子晶體或是微反射鏡陣列結構都具有高反射及繞射的效果，這些效果提供了回收發光二極體背部光線以及導正原本受限於發光二極體內部全反射(total internal reflection, TIR)的光線使其能夠小於全反射角而提升了發光二極體的出光效率。
在結構優化的過程中，討論了自我複製式光子晶體的週期與厚度對出光效率的影響，對於內嵌微反射鏡陣列結構發光二極體，則是討論微反射鏡陣列的週期尺寸與反射鏡在週期中所佔的比例(duty cycle)對出光效率的影響。

　　從模擬結果可以得知一般沒有任何提升結構的發光二極體(Standard LED, Std LED)其出光效率只有12.1%，而自我複製式光子晶體製作在發光二極體的藍寶石基板背部，出光效率最高可達36.1%，具有微反射鏡陣列結構的發光二極體在duty cycle為50%時出光效率則有50.1%。而將自我複製式光子晶體直接製作於氮化鎵發光二極體上其出光效率可達83.4%之高。

　　為了要製作具有自我複製式光子晶體的發光二極體，首先將進行自我複製式光子晶體的製作，其中包含了兩個部分，分別是二維週期基板的製作，再於二維週期基板上進行自我複製式光子晶體的鋸齒狀多層膜鍍製。

　　在二維週期基板的製作中，本論文分別嘗試以奈米壓印(nanoimprint)及雷射干涉微影(Laser interference lithography, LIL)技術來進行次微米週期結構的微影製程；奈米壓印製程的結果在模具品質不佳的狀況下造成壓印結構的形變，而雷射干涉微影所製作出的結構特徵則與曝光劑量有很大的關係，本論文針對雷射干涉微影的曝光劑量進行分析，找出能夠製作適合用來提升發光二極體出光效率的自我複製式光子晶體所需之基板，其結構尺寸為300nm週期的柱狀結構所需的曝光劑量。

　　在二維週期基板上接著製鍍Ta2O5/SiO2鋸齒狀多層膜以完成自我複製式光子晶體的製作，在此使用離子束濺鍍系統(Ion beam sputter, IBS)輔以射頻偏壓蝕刻(RF-bias etching)來鍍製鋸齒狀多層膜，同時調整射頻偏壓源的射頻功率使鋸齒狀多層膜的每一層薄膜的外貌能夠維持相同。在此部份的研究工作，我們針對了射頻偏壓偏的射頻功率進行調整，並獲得了可以成功鍍製出三維自我複製式光子晶體的射頻功率。

　　我們試著製作與理論計算相同的自我複製式光子晶體發光二極體 (auto-cloned photonic crystal LED, APhC LED)，成功製作出可在藍光氮化鎵發光二極體的450nm~470nm發光波段有高反射作用的自我複製式光子晶體，並透過將實際頻譜與模擬頻譜進行比對發現實際製作於發光二極體上的自我複製式光子晶體其厚度與設計的時分接近。將此自我複製式光子晶體製作於發光二極體藍寶石基板的背部時相較於一般的發光二極體的出光效率有97%的提升，也比在背部製作布拉格反射鏡Bragg reflector的發光二極體(BR-LED)，提升了22%的出光效率。

　　要內嵌微反射鏡陣列結構於發光二極體中，須藉由橫向磊晶技術(Epitaxial lateral overgrowth, ELOG)來完成，本論文中使用了兩階段橫向磊晶(two-step ELOG)方式並輔以慢速磊晶(slow growth)來將微反射鏡陣列結構內嵌於發光二極體中。在two-step ELOG製程中，我們探討了製程的溫度與壓力對橫向磊晶的橫向與縱向磊晶速度所造成的影響，製程條件為高溫低壓的狀況下，可以加速橫向磊晶速率與減慢縱向磊晶速率，由此獲得可以將MMA埋嵌在氮化鎵之中的製程條件，成功將MMA埋嵌在氮化鎵之中，且橫向磊晶後的氮化鎵厚度也適合繼續成長接下來的多重量子井結構，而慢速磊晶則可在幾乎不增加氮化鎵厚度的情況下，將橫向磊晶時所造成在氮化鎵表面的孔洞填平。

　　內嵌微反射鏡陣列之發光二極體(MMA LED)，相較於Std-LED的出光效率有107%的提升，也比內嵌圖案化SiO2陣列(patterned SiO2, P-SiO2)的發光二極體(P-SiO2 LED)提升了36.4 %的出光效率。

　　本論文最後提出了以雷射剝離(Laser lift-off)與基板轉換(wafer transfer)的方法來將自我複製式光子晶體直接製作於氮化鎵發光二極體上。

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