本論文中，利用雷射處理與化學濕式蝕刻技術，製作具有背面粗化增加光取出效率的發光二極體元件，經由雷射處理與濕式蝕刻後，在氮化鎵(GaN)與藍寶石基板(Sapphire)介面間產生空孔與{10-1-1}面倒立六角錐結構(Hexagonal inverted pyramid structure, HIP)，將對此結構之發光二極體元件電性與光性加以探討。本實驗將探討條紋圖案化氮化鎵模板重新成長發光二極體結構之元件(Laser treatment re-growth light emitting diode, LTRG-LED)與區域性圖案化氮化鎵發光元件(Bridge light emitting diode, Bridge-LED)兩者相對於傳統發光二極體(Standard LED, ST-LED)特性研究，將分別研究兩種圖案化氮化鎵發光元件對發光特性之影響。
實驗一，LTRG-LED使用具條紋圖案化空孔與倒立六角錐結構氮化鎵模板重新成長發光二極體結構，製作出條紋圖案化發光元件，重新成長過程中因為條紋圖案化的空孔結構，造成磊晶成長的溫度產生不均勻現象，因為空氣(0.023 W/m•k)的熱傳導比氮化鎵(1.3 w/m•k)小，週期性空孔結構使發光層銦含量的析出與波長產生週期性變化，具背後粗化的發光元件光取出效率相較於ST-LED有107%的提升，在LTRG-LED元件中觀察到波長紅移、較低的壓電場與內部量子效率提升的效應產生。
實驗二，Bridge-LED結構的製作是利用正面雷射切割、背面雷射處理與化學濕式蝕刻，製作出區域性圖案化氮化鎵發光元件，在不影響InGaN發光層之下，製作具51%粗化面積的圖案化元件，光取出效率相較於ST-LED有103%提升，發散角變小是因為氮化鎵與藍寶石基板介面間具有倒立六角錐結構，使光趨於軸向，電激發波長不變，但在大電流下半高寬有變大的趨勢，100mA操作電流下外部量子效率之衰退效率無明顯差異，製作出高取光區域性圖案化氮化鎵發光元件。
利用雷射處理與化學濕式蝕刻技術，在氮化鎵與藍寶石基板介面間產生空孔與倒立六角錐結構，利用兩種不同製程，製作高取光效率發光二極體，應用於高效率的發光元件當中。

The InGaN-based light emitting diodes (LEDs) with a roughened patterned backside on the N-face GaN surface were fabricated through a chemical wet etching process to increase light extraction efficiency. After laser treatment and the chemical wet etching process, the air-void structure with a stable chemical crystallographic {10-1-1} plane was formed at the GaN/Al2O3 interface. In this study, we analyzed optical and electrical of these two kinds of LEDs, the laser treatment re-growth light emitting diode (LTRG-LED) and bridge light emitting diode (Bridge-LED), compared to the standard LED (ST-LED).
In the first experiment, the n-GaN template with a stripe patterned air void structure and a hexagonal inverted pyramid (HIP) structure was used to re-grown LED structure. At the re-grown process, the growth temperature was distributed non-uniform on the GaN template layer with the strip-shaped air void structure. Because the thermal conductivity of the air void (0.023 W/m•k) is smaller than the GaN material (1.3 W/m•k). The indium content and the emission wavelength in the quantum well was periodic distributed corresponded to the stripe patterned air void structure. The light output power of the LED chip with the backside roughened surface had a 107% enhancement compared with the ST-LED chip. The EL wavelength redshifted, the lower piezoelectric field and the high internal quantum efficiency were observed in the LTRG-LED structure.
In the second experiment, the Bridge-LED structure was fabricated through a laser scribing, a laser treatment and a chemical wet etching process that the InGaN active layer was not damaged in the process. The light output power of the LED with a 51% backside roughened area had a 103% enhancement compared with the ST-LED. The divergent angle became small that was caused by forming the inverted pyramid shaped structures on the roughened patterned backside at the GaN/Al2O3 interface. The EL emission wavelength of both LED structures was almost the same, but the EL line-width of the treated LED structure became broadened at high injection current. A similar efficiency droop effect (about 70%) was observed for both LED structures at 100mA operating current.
The air void and the HIP structure at the GaN/Al2O3 interface were fabricated through these two kinds of processes on the GaN LED structures to enhance light extraction efficiency for the high efficiency nitride-based LED applications.

中文摘要 I
Abstract II
章節目錄 III
圖目錄 V
第一章 序論 1
1-1 照明演進 1
1-2 半導體發光二極體簡介 3
1-3 Ⅲ-Ⅴ族半導體材料 3
1-4 研究動機 4
第二章 原理與文獻回顧 5
2-1 發光二極體之發光原理 5
2-2 發光二極體之光取出效率 7
2-2.1 內部量子效率 8
2-2.2 外部量子效率 9
2-2.3 提升外部量子效率的方法 10
2-3 壓電場(Piezoelectric field)形成 18
2-3.1應變(Strain)產生 18
2-3.2壓電效應(Piezoelectric effect) 21
2-4 雷射處理 25
2-5 氮化鎵(GaN)濕式蝕刻 26
第三章 實驗方法與步驟 28
3-1 實驗設計流程圖 28
3-2 試片製備流程 28
3-3 雷射處理裝置系統 35
3-4 化學濕式蝕刻裝置 36
3-5 分析儀器 37
3-5.1 光學顯微鏡(Optical microscope) 37
3-5.2 場發射掃描式電子顯微鏡(FE-SEM) 37
3-5.3 電激發螢光光譜(Electroluminescence, EL) 38
3-5.4 發散角量測(Radiation pattern measurement) 40
3-5.5 光激發螢光系統(Photoluminescence, PL) 41
第四章 實驗結果與討論 43
4-1條紋圖案化氮化鎵模板重新成長LED結構之發光元件分析 43
4-1.1條紋圖案化氮化鎵發光元件之表面形貌 43
4-1.2 條紋圖案化氮化鎵發光元件之FE-SEM形貌 46
4-1.3 倒立六角錐與空孔結構之形成機制 49
4-1.4 條紋圖案化氮化鎵發光元件光強度分佈均勻性分析(Beam profile) 53
4-1.5 條紋圖案化氮化鎵發光元件遠場光輻射圖形 56
4-1.6 條紋圖案化氮化鎵發光元件電激發螢光光譜量測 58
4-1.7 條紋圖案化氮化鎵發光元件操作直流電流對光強度與波長之影響 60
4-1.8 條紋圖案化氮化鎵發光元件操作直流電流對電性與外部量子效率之影響 63
4-1.9 條紋圖案化氮化鎵發光元件光激發螢光光譜量測(Photoluminescence) 65
4-1.10 條紋圖案化氮化鎵發光元件改變外加偏壓探討壓電場對能帶關係 67
4-1.11 量測條紋圖案化氮化鎵發光元件之變溫光激發螢光特性 73
4-2 具區域性圖案化氮化鎵之發光二極體元件 76
4-2.1 區域性圖案化氮化鎵發光元件(Bridge-LED)之表面形貌 76
4-2.2 區域性圖案化氮化鎵之FE-SEM影像 78
4-2.3區域性圖案化氮化鎵發光元件之光強度分佈均勻性分析(Beam profile) 81
4-2.4 區域性圖案化氮化鎵發光元件之遠場光輻射圖形 83
4-2.5 區域性圖案化氮化鎵發光元件之電激發螢光與電性量測 85
4-2.6 區域性圖案化氮化鎵發光元件之電激發螢光波長與外部量子效率之影響 88
4-2.7 區域性圖案化氮化鎵發光元件之光激發螢光光譜量測 91
第五章 結論與未來展望 94
5-1 實驗結論 94
5-2 未來展望 95
參考資料 96

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