本次實驗成功於藍寶石基板上設計並成功製作出具有不同量子井結構的氮化鋁鎵/氮化鎵發光高電子遷移率電晶體(Light Emitting High Electron Mobility Transistor , LE-HEMT)。本論文著重於磊晶結構中加入p型氮化鋁鎵電子阻擋層(Electron Blocking Layer, EBL)及多量子井(Multiple-Quantum Well, MQW)的影響。
電性方面，作為對照組的單量子井發光高電子遷移率電晶體閾值電壓(Threshold Voltage, V_th) 為-0.013 V，而加入EBL與MQW結構後分別向左偏移至-1.063 V與-0.904 V。而當閘極電壓操作在5 V時，最大飽和電流在加入EBL與MQW結構後由382.42 mA/mm降低為361.71 mA/mm與238.96 mA/mm。
發光特性方面，外部量子效率(External Quantum Efficiency, EQE)在加入EBL與MQW結構後由0.198 %分別提升為0.199 %與 0.217 %。另外對於效率下降(Efficiency Droop)也有改善，在加入EBL與MQW結構後由0.0916 %分別降低至0.0407 %與 0.0194 %。
本次實驗也探討了不同佈局結構對於氮化鋁鎵/氮化鎵發光高電子遷移率電晶體的影響，包含：線性、圓形、指叉狀與四顆圓形並聯的佈局。

In this thesis, AlGaN/GaN light-emitting high electron mobility transistor (LE-HEMT) with different quantum well structures on sapphire are demonstrated. We focus on the impact of adding a p-AlGaN electron blocking layer (EBL) and multiple-quantum well (MQW) in the epitaxy.
The threshold voltage (V_th) of a baseline LE-HEMT with a InGaN single quantum well is -0.013 V, which shifts to -1.063 V and -0.904 V after inserting EBL and MQW, respectively. When the gate voltage is 5 V, the maximum saturation current for the LE-HEMT with InGaN single quantum well is 382.42 mA/mm, which decreases to 361.71 mA/mm with the EBL and 238.96 mA/mm with the MQW.
In terms of light emitting characteristics, the external quantum efficiency (EQE) is 0.198%, 0.199% and 0.217% with EBL and MQW, respectively. Efficiency droop decreases from 0.0916% to 0.0407% and 0.0194% after inserting the EBL and MQW.
Furthermore, we also study AlGaN/GaN LE-HEMTs with different device layouts, including linear, circular, multi-finger, and four paralleled circular layouts.

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