本論文中，我們首次以氧化銦錫作為p-GaN gate元件之歐姆接觸閘極金屬並成功以矽基板之P型氮化鎵/氮化鋁鎵/氮化鎵磊晶結構製作出高電子遷移率電晶體(HEMT)及發光高電子遷移率電晶體(LEHEMT)，經由良好的P型氮化鎵蝕刻深度控制，兩者之臨界電壓(threshold voltage)皆為0.2V，最大轉移電導為96.6mS/mm、104.68mS/mm，在閘極電壓為1V時定義其導通電阻(specific on-state resistance, Ron,sp)HEMT為2.43 mΩ-cm2 、LEHEMT為4.74 mΩ-cm2。並進一步對此元件進行可靠度研究，發現以氧化銦錫作為閘極金屬雖然有稍大的閘極漏電流產生，在閘極電壓應力及長時間電壓應力等可靠度測試中仍有不錯的特性。
此外LEHEMT擁有良好的發光特性，於閘極電壓(Vg)為3V、汲極電壓(Vd)為10V時，發出波長為363.3 nm之紫外光，同時可透過調變Vg及Vd有效地控制發光強度。另外，本實驗也透過不同的光罩設計作為比較，發現汲極在中央的環型結構能使發光更集中，期待能夠使用在光通訊與主動式矩陣等相關應用。

In this study, we demonstrated the p-GaN gate HEMT with ITO P-ohmic electrode for the first time. HEMT and LEHEMT were successfully fabricated with p-GaN/AlGaN/GaN epitaxial layers on silicon substrates. With precise p-GaN etching control, threshold voltage of 0.2 V was obtained in both devices, the maximum transconductance of HEMT and LEHEMT was 96.6ms/mm and 104.68ms/mm respectively. At Vg = 1 V, the specific on-state resistance of these two devices were 2.43 mΩ-cm2 and 4.74 mΩ-cm2. Furthermore, we investigate preliminary reliability of the fabricated devices. Even though the gate leakage current of ITO p-GaN gate HEMT was slightly higher, the results from gate stress and long-term stress reliability test still showed very good characteristics.
Besides, the good optical properties of LEHEMT was observed at Vg = 3 V and Vd = 10 V. The wavelength of the emitted light was 363.3 nm. The light output intensity can be modulated by the gate voltage and the drain voltage. Light patterns with different layout designs are also compared in this study for future applications in optical communication and active matrix LEDs.

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