本論文主要研究有機發光二極體元件之發光層PVK: Rubrene進行材料性質的分析，進而製成有機發光元件 (元件大小為0.25 cm2)，並量測光電特性。研究主要分為五個部分：(1) 客體材料Rubrene摻雜濃度、(2) 發光層厚度、(3) 元件電流理論擬合、(4) 發光層烘烤溫度、(5) 視角對應光強度變化，探討不同影響因子對於元件光電特性之影響。
客體材料摻雜濃度會影響元件發光效率，故設計元件結構為：ITO (125 nm)/ PEDOT: PSS (65 nm)/ PVK: x wt% Rubrene (65 nm)/ Al (100 nm)，其中摻雜5 wt% Rubrene的發光層有最佳光電特性：T=91%、Vth=10.4V、Lmax=0.14 cd/m2。
發光層的厚度影響了自由載子的傳輸與復合行為，所以研究元件結構為：ITO (125 nm)/ PEDOT: PSS (65 nm)/ PVK: 5 wt% Rubrene (y nm)/ Al (100 nm)，發現厚度為65 nm的發光層有最佳光電特性：Vth=10.6V、Lmax=0.27 cd/m2；並且分析其電流理論，發現電壓在臨界電壓10.6V以前，其電流-電壓曲線利用公式擬合得到I ~ V，得知元件滿足電流遵守歐姆傳導；電壓在臨界電壓10.6V以後，電流-電壓曲線利用公式擬合得到I ~ V^2，得知元件的電流遵守空間電荷限制電流。
另外，探討烘烤溫度對元件的影響，因此利用元件結構為：ITO (125 nm)/ PEDOT: PSS (65 nm)/ PVK: 5 wt% Rubrene (65 nm)/ Al (100 nm) 改變烘烤溫度，觀察到發光層烘烤溫度100℃有最佳光電特性：T=95.5%、Vth=8.8V、Lmax=0.18 cd/m2。
最後，由角度對應光強度變化的結果，發現元件並不會在某特定角度出現較高的光強度，因此推論此元件結構不具備共振腔之光學特性。

In this study, the active layer of organic light-emitting devices (OLEDs) of PVK: Rubrene are analyzed material properties and measured OLEDs electrical-optical characteristics. OLEDs structures are ITO (125 nm)/ PEDOT: PSS (65 nm)/ PVK: x wt% Rubrene (y nm)/ Al (100 nm). Each device area is 0.25 cm2.
Because of the quenching effect, the active layer of OLEDs doped with 0, 5, 10, 15 wt% Rubrene are investigated. The OLED of the active layer doping with 5 wt% Rubrene has the best electrical-optical characteristics: the transmittance is 91%, the threshold voltage is 10.4V, and the maximum luminous intensity is 0.14 cd/m2.
The thickness of the active layer will affect the mobility of carriers and recombination. OLEDs of the active layer with thickness 42, 65,101 nm are designed. The OLED of the thickness of the active layer is 65 nm has the best electrical-optical characteristics: the threshold voltage is 10.6V, and the maximum luminous intensity is 0.27 cd/m2.
To discuss the influence of baking temperature on OLED of the active layer, OLEDs with the active layer baking at 60, 80, 100, 120℃ are proposed. The OLED of the active layer baking at 100℃ has the best electrical-optical characteristics: the transmittance is 95.5%, the threshold voltage is 8.8V, and the maximum luminous intensity is 0.18 cd/m2. And the luminous intensity does not increase at a specific angle, so that it does not have the micro-cavity in the OLED.

論文審定書 i
致謝 ii
中文摘要 iii
Abstract iv
目錄 v
圖目錄 viii
表目錄 xi
第一章、緒論 1
1.1 有機電致發光之發展歷史 1
1.1.1 有機發光二極體 (OLED) 之簡介 1
1.1.2 高分子電激發光二極體 (PLED) 之簡介 4
1.1.3 OLED與PLED之比較 6
1.2 元件結構 8
1.2.1 單層元件結構 8
1.2.2 多層元件結構 8
1.3 研究動機 11
1.4 論文大綱 11
第二章、理論基礎 13
2.1 發光原理與機制 13
2.1.1 發光原理 13
2.1.2 發光機制 13
2.2 有機材料的介紹 15
2.2.1 電洞注入與電洞傳輸材料 16
2.2.2 電子傳輸材料與發光層主體材料 19
2.2.3 電極材料 21
2.3 載子的注入與傳輸 21
2.3.1 電荷注入 21
2.3.2 電荷傳導 24
2.4 內、外部量子效率 29
第三章、實驗流程 30
3.1 實驗架構 30
3.2 實驗材料 30
3.3 溶液的配製 31
3.3.1 PEDOT: PSS材料 31
3.3.2 PVK: Rubrene材料 31
3.4 實驗步驟 31
3.4.1 基板清洗 31
3.4.2 濺鍍ITO當陽極 32
3.4.3 旋轉塗佈有機溶液 32
3.4.4 蒸鍍陰極 32
3.5 儀器設備 33
3.5.1 製程儀器 33
3.5.2 量測儀器 37
第四章、實驗結果與討論 40
4.1 PVK摻雜不同Rubrene濃度 40
4.1.1 PVK: x wt% Rubrene薄膜分析 40
4.1.2 PVK: x wt% Rubrene元件分析 41
4.2 改變發光層厚度 43
4.3 電流理論擬合分析 45
4.4 改變發光層烘烤溫度 46
4.4.1 發光層的烘烤溫度之薄膜分析 46
4.4.2 發光層的烘烤溫度之元件分析 47
4.4 視角對應光強度分析 49
第五章、結論 51
參考文獻 52
Published 59

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