臺灣博碩士論文加值系統

在本篇論文中，我們使用一新合成之OXD衍生物作為發光層的發光主體，一般來說，OXD具有電子傳輸特性，將以此新材料與carbazole 為基底之主體材料，如CBP，做比較。驅動電壓方面，電流密度在100mA/cm2時，CBP基底元件為13.5V，而OXD基底的驅動電壓則為11V。而在亮度為10000cd/m2時，電流效率則由24cd/A降為到21cd/A。而在亮度為1000cd/m2時,能量效率則由8 lm/W上升到10 lm/W。
此外，我們將紅光磷光摻雜材料混入傳統電子或電洞傳輸材料中，並比較在沒有電洞阻擋層情況下元件表現，進而判斷對精簡元件結構，電洞阻擋層是否需要。實驗結果顯示，這些新結構相較於傳統元件將能有效的降低操作電壓。此外，在亮度為50 cd/m2時候，我們以電子傳輸材料作為主體且搭配電洞阻擋層的元件展現的電流效率約為16.1cd/A。這些元件還展現出較為和緩的三重態--三重態消滅。

In this thesis, we demonstrated phosphorescent organic light-emitting devices (PHOLEDs) by using a novel host material and two transporting materials as the host of PHOLED. We used an n-type transporting material as the host of green PHOLED. Due to the better energy alignment with adjacent transporting materials, our device exhibits a lower turn-on voltage by about 2.5 volts with the current density of 100 mA/cm2 as compared to the conventional carbazole OLED. The power efficiency is increased from 8 to 10 lm/W at the luminance of 1000 cd/m2.However, the current efficiency at 10000 cd/m2 is slightly decreased from 24 to 21 cd/A.
Besides, we used two conventional transporting materials as the host of the red PHOLED and evaluate the necessity of the hole blocking layer (HBL) by using two Ir (iridium) based red emitter. Device with electron transporting material as the host with HBL structure exhibited the highest current efficiency of 16.1 cd/A at the luminance of 50 cd/m2. Besides, devices showed limited triplet-triplet annihilation.

Chapter 1 Introduction 8
1.1 Backgrounds 8
1.2 Machanism of Phosphorescent OLED 10
1.3 Phosphorescent OLED 11
1.4 Motivation 14
1.5 Thesis Organization 15
Chapter 2 Experimental Setup 24
2.1 OLED Device Fabrication 25
2.2 Characteristics of Organic Materials Measurement 26
2.3 B-I-V and Lifetime Measurement 28
2.4 External Quantum Efficiency (EQE) Calculation 29
Chapter 3 Green Phosphorescent OLED with an N-type Host Material……………………………………. 35

3.1 Novel Host Material for PHOLED 37
3.2 Results and Discussion 38
Chapter 4 Red Phosphorescent OLED with Different Transporting Materials as the Host 53
4.1 High Efficient Red PHOLED with Simplified Device Structure… 54
4.2 Results and Discussion of Ir(pq)2-based Red PHOLED…………………………………………………... 55
4.2 Results and Discussion of IrB2-based Red PHOLED…………………………………………………... 59
Chapter 5 Conclusions 88
References 94

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