目前有機發光二極體(OLED)顯示器具備了高亮度、高對比度、超薄、可撓曲且重量輕之絕佳優勢，可望取代使用已久的液晶顯示器。OLED目前面臨的最大挑戰為壽命問題，因此本研究藉由無機材料的高載子遷移率(mobility)與穩定性等優勢，對有機材料進行置換，可讓元件的發光亮度提高，並且提升其耐用性，進而延長使用壽命。本論文以無機氮化鎵(GaN)以及氮化鎵/氮化鋁鎵(AlGaN)結構對傳統的電子傳輸層兼電洞阻擋層BCP進行置換，並且製作有機、無機複合式OLED元件。
本研究分為兩部分，第一部分以實驗室自行開發的電感耦合電漿輔助射頻濺鍍系統沉積氮化鎵，其具備了易大面積化與設備成本低的優勢。藉由ICP電漿所提供的額外能量，本研究成功於500℃低溫下獲得單晶高品質GaN薄膜，結晶方向為(0002)，XRD鑑定結果之半高寬值為12.5 arcmin(文獻最佳結果約5~15 arcmin)且無氮空缺之問題。
第二部分為應用上述之電感耦合電漿輔助射頻濺鍍系統沉積氮化鎵於AZO透明玻璃基板之上，藉由AZO提供的優選方向(prefer orientation)成長出高品質的GaN薄膜，並以熱蒸鍍系統完成後續複合式OLED元件製作。起初元件僅採用GaN取代BCP，元件的最高亮度為690 cd/m2，低於傳統OLED元件的最高亮度2575 cd/m2。後續再以GaN/ AlGaN結構取代BCP，結果成功將最高亮度提升至4490 cd/m2，大幅超越傳統元件，但起始電壓較高(12.0 V)，並且藉由實驗確認GaN/ AlGaN結構確實具備良好的電洞阻擋效果，可成功取代BCP，並且提升元件整體的耐用性。

Organic light emitting diode (OLED) displayers have excellent advantages of high brightness, high contrast, thin, flexible and light weight, so OLEDs have potential to replace LCD displayers. The most crucial problem of OLEDs is lifetime. In this study, we focus on solving this problem by using inorganic material that has high carrier mobility and stability to replace organic material. Within the hybrid OLED structure, the devices have higher brightness, better durability, and prolong the lifetime of OLEDs. In this study, we utilized gallium nitride (GaN) and GaN/ aluminum gallium nitride (AlGaN) structure to replace traditional hole blocking layer and electron transport layer, BCP, then fabricated organic-inorganic hybrid OLED devices.
Two subjects have been studied as follows. The first part was deposition of GaN film by inductively coupled plasma (ICP) enhanced magnetron sputtering system which had advantages of low equipment cost and large-scale production. With extra energy provided by ICP plasma, we obtained high quality single-crystal GaN thin film under low temperature, 500℃. The preferential orientation of the film was along (0002) direction. By XRD identification result, the full width at half maximum (FWHM) value of the GaN (0002) peak was 12.5 arcmin (the best results in literature were 5 ~ 15 arcmin), and there was no nitrogen vacancy issue.
The second part was to apply inductively coupled plasma enhanced magnetron sputtering system to deposit high quality GaN film on AZO glass substrate which provided prefer orientation, and completed hybrid OLED device by thermal evaporation system. First, we only used GaN film to replace BCP, the maximum brightness of this device was 690 cd/m2 which was lower than traditional device, 2575 cd/m2. Next step, we used GaN/ AlGaN structure to replace BCP and enhanced maximum brightness to 4490 cd/m2 successfully which significantly exceeded tradition OLED devices. However, the turn-on voltage (12.0 V) was higher than literature values. Then, we confirmed GaN/ AlGaN structure has excellent effect for blocking holes. We replaced BCP organic layer successfully and improved the durability of devices.

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