本研究有兩個主題，其一為複合受激態之有機發光二極體的效率提升。其二為複合受激態觸發三重態-三重態消滅藍色有機發光二極體之效率提升。
複合受激態 (Exciplex) 為兩有機材料，分別具電子施體與電子受體特性，在界面處形成激發態的錯合物。我們針對使用複合受激態之有機發光二極體，調變厚度與混合比例來優化，得到6.57 % 外部量子效率及20.95 lm/W 之功率效率。
再者為研究複合受激態觸發三重態-三重態消滅藍色有機發光二極體 (Exciplex sensitized triplet-triplet annihilation ,簡稱ESTTA)。此系統由複合受激態經能量傳遞給藍色三重態-三重態消滅 (Triplet-triplet annhiliation, 簡稱TTA) 發光體，產生上轉換 (Upconversion) 的放光。其效率可能因單重態激子猝熄而降低。故本章以兩種手段，改善此系統的能量傳遞路徑，增加藍光效率。其一為加入藍色螢光客體材料4,4''-bis[2-(4-(N,N-diphenylamino)phenyl)vinyl]biphenyl) (DPAVBi)，其二為插入 4,7-diphenyl-1,10-phenanthroline (BPhen) 作為三重態傳遞和單重態阻隔層 (Triplet diffusion and singlet blocking,簡稱TDSB)。在既摻雜客體材料亦插 TDSB 層之元件，能提升外部量子效率的藍色分量至2.316%。
上述研究皆屬於延遲型螢光放光，因此我們利用暫態電激發光 (Transient electroluminescence, 簡稱TrEL) 量測系統，來分析這種延遲放光。透過量測電訊號關掉後的電激放光，藉此研究激子於元件中的物理機制，以及能量轉移的過程。

There are two topics in this thesis. The first one is the optimization of exciplex-based organic light-emitting diode (OLED). The second part describes the methods to improve the efficiency of exciplex sensitized triplet-triplet annihilation (ESTTA) OLED.
When two organic materials act as electron donor and acceptor respectively and form the excited complexes at their interface, it is called exciplex. We optimized exciplex-based OLED to achieve higher efficiency by means of layer structure tuning. Finally, the power efficiency of 20.95 lm/W and external quantum efficiency (EQE) of 6.57% were obtained.
Exciplex generated by two species could transfer its energy to triplet-triplet annihilation (TTA) blue emitter, and created energy upconversion blue emission afterwards. We called this process exciplex sensitized triplet-triplet annihilation (ESTTA). Here, two methods have been adopted to improve the efficiency, which were: (1) doping blue fluorescence dye: 4,4''-bis[2-(4-(N,N-diphenylamino)phenyl)vinyl]biphenyl) (DPAVBi), and (2) inserting 4,7-diphenyl-1,10-phenanthroline (BPhen) as “triplet diffusion and singlet blocking (TDSB)” layer. By employing dopant combined with TDSB layer, ESTTA-OLED increased its blue EQE to 2.316%.
In these OLEDs, transient electroluminescence (TrEL) were employed to investigatet the carrier and exciton dynamics by measuring the turn-off responses.

目錄 I
圖目錄 III
表目錄 X
第1章 緒論 1
1.1 OLED的基礎知識 1
1.2 Exciplex與TTA，以及利用兩者的ESTTA 7
1.3 實驗動機 12
第2章 製程及量測系統 13
2.1 簡介 13
2.2 元件製程 13
2.3 量測系統 15
2.3.1 穩態 B-J-V 量測 15
2.3.2 暫態電激發光 (Transient electroluminescence，TrEL) 量測系統 16
第3章 具備複合受激態發光層有機發光二極體之元件優化 17
3.1 實驗動機與本章簡介 17
3.2 調變電子傳輸層厚度 19
3.3 變化發光層厚度 22
3.4 調變發光層混合比例 26
第4章 複合受激態觸發三重態-三重態消滅有機發光二極體之效率提升 30
4.1 實驗動機與本章簡介 30
4.2 優化ESTTA元件厚度 34
4.2.1 增厚電子傳輸層 34
4.2.2 增厚電洞傳輸層 40
4.2.3 ESTTA/ TTA/ Exciplex 控制元件比較 45
4.3 加入 DPAVBi 藍光客體材料，調變摻雜濃度 50
4.4 插入BPhen作為 TDSB 層，調變插入厚度 57
4.5 固定 TDSB = 1 nm 並調變發光層與電子傳輸層厚度 65
4.6 同時摻雜客體材料及插入 TDSB 層 71
第5章 結論 76
參考資料 78
附錄 84
第三章複合受激態優化過程，剛復機完，曾做出高效率元件 84

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