臺灣博碩士論文加值系統

在有機材料中電洞的移動率(μp)比電子移動率(μn)快，大量的電洞將降低發光效率；因此，平衡電洞與電子的量為重要的研究課題。
因為CuPc 材料比Alq材料有較好的電子遷移率，所以本研究主要是使用CuPc 來代替Alq 材料，在有機發光二極體中充當電子傳輸層。元件結構有下列二種型式：ITO/CuPc/NPB/BCP/Alq/LiF/Al 與 ITO/CuPc/NPB/BCP/CuPc/LiF/Al，實驗結果顯示以CuPc作為電子傳輸層的結構中，電子傳輸現像增強並導致元件操作電壓的降低。發光的CIE 座標是(0.15, 0.07)，非常接近藍光的座標點(0.14, 0.08)。

In organic materials the hole mobility(μp) is usually orders of magnitude larger than the electron mobility(μn), resulting in a dominant hole current that lower the electroluminescent efficiency. Therefore, to balance electrons and holes in emitting layer is an important topic.
Organic light emitting diodes (OLEDs) employing cooper phthalocyanine (CuPc), instead of tris-(8-hydroxguinoline) aluminum (Alq), as an electron transporting layer are fabricated, because the CuPc has better electron mobility than Alq. The characteristics of OLEDs with ITO/CuPc/NPB/BCP/Alq/LiF/Al and ITO/CuPc/NPB/BCP/CuPc/LiF/Al strctures are studied. The outcome of this structure with a CuPc electron transporting layer significantly facilitates electrons transporting through the organic materials, thus resulting in the reduction of operating voltages. The Commission International de l’Eclairage (CIE) coordinates of the emitted light are (0.15, 0.07 ), which are just near to the blue-light equi-energy point (0.14, 0.08).

Content
Abstract (in Chinese)
Abstract (in English)
Acknowledgments
Content
Table Captions
Figure Captions
Chapter 1 Introduction
1-1 Brief history of organic light emitting diodes 1
1-2 Comparison of OLED and other panel displays 3
Chapter 2 Review of Literature
2-1 The operation theory of OLEDs 5
2-2 Quantum Efficiency of OLEDs 7
2-3 The Structure of OLEDs 10
2-3-1 Electrode of OLEDs 10
2-3-2 Hole-blocking layer 12
2-4 Degradation 13
Chapter 3 Experimental Procedure and System Description
3-1 Material 15
3-2 Substrate etching and cleaning 16
3-3 Vacuum evaporation system 16
3-4 Deposition of organic thin films 17
3-5 Deposition of electrodes 18
3-6 Measurement 19
3-6-1 Electroluminescence spectroscopy 19
3-6-2 Current-voltage measurement 19
3-6-3 Luminance measurement 19
3-6-4 CIE measurement 20
3-6-5 Ultraviolet-visible spectroscopy (UV-Vis)
3-6-6 Luminous efficiency
3-6-7 External quantum efficiency 20
21
21
Chapter 4 Results and Discussion
4-1 ITO/CuPc/NPB/ETL/LiF/Al Structure 25
4-2 ITO/ CuPc (x nm)/NPB/BCP/CuPc/LiF/Al Structure with x=0,5,10,15,20nm 26
4-3 ITO/CuPc/NPB/BCP (x nm)/CuPc/LiF/Al Structure with x=5,10,15,20nm 26
4-4 ITO/CuPc/NPB/BCP/CuPc (x nm) /LiF/Al Structure with x=5,10,25,40nm 27
Chapter 5 Conclusions
5-1 Conclusions 28
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