臺灣博碩士論文加值系統

我們將利用高真空蒸鍍系統，在透明的導電陽極-氧化錫銦玻璃基板上成長有機薄膜與金屬陰極，進而完成有機電激發光元件的製備。在研究過程中，我們將利用多層結構的方法來完成有機電機發光元件的研製，其完整結構為透明陽極/電洞傳導層/紅光發光層/電子傳導層/金屬陰極。而在紅光發光層部份，我們利用不同的紅光摻雜材料搭配主體材料進而完成紅光有機電激發光元件。
經我們研究證實利用不同的紅光摻雜材料可以得到高效率的紅光有機電激發光元件。其中利用紅光摻雜材料DCJTB所製成的紅光有機電激發光元件其發光機制主要是藉由能量轉移的方式將主體材料的發光能量轉移給摻雜材料，進而讓摻雜材料發光，若加入的紅光摻雜材料為NIR，則其主要的發光機制乃是經由載子捕捉的方式來發出紅光。但是，若使用的紅光摻雜材料為DCM2，則能量轉移及載子捕捉兩種發光機制將同時發生，也因此利用DCM2可以得到最亮的紅光有機電激發光元件。
另一方面，我們又進一步證明了利用增感材料Rubrene可得到更亮且發光純度更純的紅光有機電激發光元件。我們主要是利用共摻雜的技術來製作紅光發光層，其中加入增感材料Rubrene可以讓主體材料所發出的光更有效率的提供給紅光摻雜材料DCJTB，也因此我們又更進一步的得到更高亮度與純度的紅光有機電激發光元件。

Organic light emitting devices were deposited on Indium tin oxide (ITO) substrate by high vacuum evaporator system. In our study, the device configurations of red OLEDs using multilayer structure were ITO/ NPB (600 Å)/emitting layer (500 Å)/Alq3 (500 Å)/Mg:Ag (1500 Å) with various red dopant, providing a red-light emission from emitting layer.
We have demonstrated a highly efficient red-light OLED doped with various red dye materials. Evidence showed that the correspondingly dominant emitting mechanisms for both DCJTB and NIR-doped devices are the exciton energy transfer and carrier trapping, respectively. Besides, it is strongly suggested that the co-existence of excition energy transfer and carrier trapping processes in DCM2-doped OLED is the main reason leading the highest luminance occurred in that device.
On the others hand, we have proved a bright red emission of OLED based on an emitting layer codoped with DCJTB and rubrene. The dominant emission mechanism is the exciton energy transfer causing the enhancement of brightness and purity.

Publications and Preprints I
ABSTRACT (in Chinese) II
ABSTRACT (in English) IV
Acknowledgment VI
FIGURE CAPTION VII
CONTENTS IX
Chapter 1. Introduction 1
1.1 Background 1
1.2 Motivation 2
1.3 Organization of This Thesis 3
Chapter 2. Basic Concepts and Experimental Procedure 4
2.1 Basic Concepts 4
2.1.1 Electroluminescence in Organic Materials 4
2.1.2 Charge Carrier Injection and Transport 4
2.1.3 Luminescent Mechanisms of Organic Materials 5
2.2 Experimental Procedure 6
2.2.1 ITO Substrate Etching and Cleaning 6
2.2.2 Deposition of Organic Thin Films and Electrodes 7
2.2.3 Measurement 8
Chapter 3. Influence of Various Red Doping Materials on the Photoelectric Performance of Highly Efficient Organic
Light-Emitting Devices 9
3.1 Introduction 9
3.2 Experiments 10
3.3 Results and Discussion 10
3.4 Conclusions 13
Chapter 4. Influence of Rubrene on the Optoelectrical Performance of
Red Organic Light-Emitting Diodes 14
4.1 Introduction 14
4.2 Experiments 14
4.3 Results and Discussion 15
4.4 Conclusions 16
Chapter 5. Suggestions for Future Work 17
References
Figures
Biography

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