臺灣博碩士論文加值系統

本實驗主要針對傳統發光二極體(Light Emitting Dideo, LED)前段製程中的磊晶結構上進行改善。具體方法為在p型氮化鎵(p-GaN)層前加入一層p型氮化鋁鎵(p-AlGaN)，形成電子阻擋層，減少溢出之電子，達到提升電子、電洞結合的效率，以期能提升亮度等相關電性。實驗過程測試了多種p-AlGaN厚度如10 nm、20 nm、30 nm、40 nm與50nm等，實驗結果表明以30 nm 效果最佳，且其他電性並無明顯變差。故以此實驗條件，經連續測試多次，驗證其再現性，最後實驗結果顯示其亮度提升近3%。

關鍵字：發光二極體、p型氮化鎵、p型氮化鋁鎵、亮度、磊晶、電子阻擋層、厚度、摻雜、電性提升

This study aims to improve the epitaxy structure in the front-end process of traditional light emitting diode (LED). A layer of p-AlGaN is specifically added before the p-GaN layer to form the electron blocking layer for reducing overflown electrons and enhancing the efficiency to combine electrons and electron holes, expecting to promote electrical properties such as luminance. Several p-AlGaN thicknesses, e.g. 10 nm, 20 nm, 30 nm, 40 nm, and 50nm, are tested in the experiment. The results show the best effect of 30 nm, and other electrical properties do not obviously get worse. The experiment conditions are therefore tested for several times to verify the reproducibility. The final experimental result revel the promotion of luminance about 3%.

Keywords: Light emitting diode, p-GaN, p-AlGaN, Luminance, Epitaxy, Electron blocking layer, Thickness, Doping, Improvement of electrical property.

誌謝辭………………………………………………………………………i
中文摘要……………………………………………………………………ii
英文摘要……………………………………………………………………iii
目錄…………………………………………………………………………iv
圖目次………………………………………………………………………vi
第一章 背景、動機與目的………………………………………………1
1.1 背景………………………………………………………………1
1.2 動機………………………………………………………………3
1.3 目的………………………………………………………………4
第二章 文獻回顧………………………………………………………… 5
2.1 文獻回顧一………………………………………………………5
2.2 文獻回顧二………………………………………………………7
2.3 文獻回顧三………………………………………………………9
2.4 文獻回顧四………………………………………………………11
第三章 研究方法………………………………………………………… 14
3.1 研究流程圖………………………………………………………14
3.2 研究設備 ……………………………………………………… 15
3.2.1 有機金屬化學氣相沉積系統(MOCVD)…………………… 15
3.2.2 金相顯微鏡…………………………………………………15
3.2.3 光激螢光光譜量測系統(PL)………………………………16
3.3 GaN LED 結構.………………………………………………… 18
3.4 GaN => p-AlGaN…………………………………………………19
第四章 研究結果與討論………………………………………………… 21
4.1 外觀檢測…………………………………………………………21
4.2 PL 波長與均勻性量測………………………………………… 23
4.3 合金電性資料……………………………………………………23
4.4 結果與討論………………………………………………………38
第五章 結論與未來工作…………………………………………………39
參考文獻……………………………………………………………………40

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