摘要
最近幾年來有機電致發光元件由於其具有低成本、結構簡單、無視角及低耗電量等優點而被廣的研究，更被譽為下一世代的顯示器主流，而且極有可能會取代目前顯示器的主流TFT-LCD，但是由於其本身的有機材料對於水氧極其敏感，元件生命期過短為目前最主要需要突破的問題之ㄧ。為了能有效遏止有機電致發光元件衰退，已經有多項研究積極進行，其中的一項就是於元件整體上沉積一層具高抗水、氧氣滲透的薄膜以阻隔其對元件的損害。由於矽的活性很高，因此在具有良好阻的薄膜以阻隔其對元件的損害為非常關鍵的技術。由於矽的活性很高，因此在具有良好阻障性且高透光率的氧化矽膜或氮化矽膜中，可將滲透進阻障薄膜的水、氧氣捉住，達到更好的阻障特性.
本次實驗中，我們著重於保護層的選擇和研究其特性，對於保護層薄膜做膜厚量測確定其沉積厚度，量測薄膜的穿透率，並且針對薄膜做透濕性和密度的量測，以便選出對於OLED元件最好的保護層，然後應用到元件上。最後再加上玻璃封蓋和吸濕材料氧化鋇完成元件的封裝。把有鍍不同保護層的元件，和沒有做封裝保護的元件做比較，再放入恆溫恆濕櫃中，作壽命量測。分別以電壓對電流、電壓對亮度、時間對亮度、陰極表面形態和暗點的產生做研究探討。從實驗所得結果可以發現保護層對於OLED元件的影響很大，確實能夠使元件的壽命延長。

Abstract
The Organic Light Emitting Diode (OLED) was extensively studied due to its superior properties of low cost, simple structure, wide viewing angles and low power consumption etc. It has been praised as the mainstream of displays for next generation. The TFT-LCD will replace by the OLED display in the feature. However, the organic was sensitive to oxygen and moisture. So the short lifetime was the main problem that needs to solve. The SiOx or SiNx layer is used as a barrier layer for trapping the oxygen and water vapor permeated through SiOx or SiNx layer.
In this study, we deposited different kinds of the passivation layer. To measure their thickness, light-transported, density and water permeation. The film was applied on the OLED device, then encapsulation by using the glass cap and hygroscopic agent. The encapsulated OLED device compared the characters with the non-encapsulated OLED device, and measured their lifetime in the stable temperature and humidity. We discussed the relationship of voltage-current, voltage-luminance, time-luminance, cathode morphology and dark spots. The result of the experiment has showed that the lifetime of the OLED device could be increased via effective encapsulation.

Content
Abstract (in Chinese)………………………………………………………iv
Abstract (in English)……………………………………………………...v
acknowledgement……………………………………………………………….vi
Figure and Table captions…………………………………………………ix
Chapter 1 Introduction………………………………………………………3
1-1 The develop of organic emitting-light diode…….…………5
1-2 The purpose of this study……………………………………………6
Chapter 2 Principle of basis……………………………...........9
2.1 Theory of Fluorescence and Phosphorescence…………………9
2.2 The principle of Electroluminescence…………………………10
2.3 The organic material…………………………………………………12
2.4 The degradation mechanism of OLEDs……………………………14
Chapter 3 Experimental Procedures and Systems.……………….20
3-1 Experimental equipment...………………………………………..20
3-1-1 The light-transport of the substrate measure…………20
3-1-2 The sheet resistance of the substrate measure………20
3-1-3 The thickness of the deposited film measure………….21
3-2 Experimental preparation …….…………………………………21
3-2-1 Substrate Cleaning ………………………………………………21
3-2-2 Substrate etching process………………………………………22
3-3 Growth system and procedures…………………………………….23
3-3-1 Deposition system .…….…….….………………………………23
3-3-2 Deposition of thin films ………………………………………23
3-3-3 Deposition of electrodes……………………………………….24
3-4 Encapsulation procedure……………………………………………25
3-4-1 RF magnetron sputtering system………………………………25
3-4-2 Evaporating of passivation layer………………………....26
3-4-3 Encapsulation procedure………………………………………..27
3-5 Measurements……………………………………………………………27
3-5-1 Electrical characteristics........................27
3-5-2 Optical characteristics……………………………………...28
3-5-3 Surface morphology……………………………………………..28
Chapter 4 Results and discussion…………………………………..32
Chapter 5 Conclusions…………………………………………………….43
Reference………………………………………………………….……………46

Figure Captions
Chapter 2
Fig. 2-1 The OLED structure………………………………………………51
Fig. 2.2 The HTL materials which we often used were TPD and NPB……………………..........................................52
Fig. 2.3 The EL materials which we often used was Alq3………53
Chapter 3
Fig. 3.1 The marshal OLED system was used for the process of the film……………….............................................54
Fig. 3.2 The measurement of four point probe………………………55
Fig. 3.3. The schematically structural diagram of α-step……56
Fig. 3.4. The process of the OLED device……………………………57
Fig. 3.5. The diagram of CIE measured…………………………………58
Chapter 4
Fig. 4.1. I-V characteristics of OLEDs passivated by difference passivation layer…..…......................................59
Fig. 4.2. Luminance-voltage curves of OLEDs passivated by difference passivation layer………………………………………………………….……60
Fig. 4.3. Luminance-Power plots of OLEDs passivated by difference passivation layer.. ........................................61
Fig. 4.4. Efficiency-voltage curves of OLEDs passivated by difference passivation layer.................................62
Fig. 4.5. The lifetime of OLEDs passivated by difference passivation layer at the condition
(25 ℃, 40% RH)...............................................63
Fig. 4.6. I-V characteristics of OLEDs passivated by various thickness SiO2 layers…….....................................64
Fig. 4.7. Luminance-voltage curves of OLEDs passivated by various thickness SiO2 layers………………………………………………………....65
Fig. 4.8. Luminance-Power plots of OLEDs passivated by various thickness SiO2 layers.........................................66
Fig. 4.9. Efficiency-voltage curves of OLEDs passivated by various thickness SiO2 layers…………………………………………………...………67
Fig. 4.10. The lifetime of OLEDs passivated by various thickness SiO2 layers at the condition (25℃, 40% RH)…………………………….68
Fig. 4.11. I-V characteristics of OLEDs with and without the glass cap……..……………..............................................69
Fig. 4.12. Luminance-voltage curves of OLEDs with and without the glass cap…………...............................................70
Fig. 4.13. Luminance-Power plots of OLEDs with and without the glass cap……..…..….................................................71
Fig. 4.14. Efficiency-voltage curves of OLEDs with and without the glass cap……….…..............................................72
Fig. 4.15. The lifetime of OLEDs with and without the glass cap at the condition (25 ℃, 40% RH)…………….…………………….…………….73
Fig. 4.16. I-V characteristics of OLEDs passivated by difference passivation layer……….........................................74
Fig. 4.17.Luminance-voltage curves of OLEDs passivated by difference passivation layer..............................................75
Fig. 4.18.Luminance-Power plots of OLEDs passivated by difference passivation layer………......………………………………………………...76
Fig. 4.19.Efficiency-voltage curves of OLEDs passivated by difference passivation layer…………………...……………………………77
Fig. 4.20.The lifetime of OLEDs passivated by difference passivation layer at the condition(25 ℃, 40% RH)………………….…………………78
Fig. 4.21. I-V characteristics of OLEDs passivated by difference metal layer…..................................................79
Fig. 4.22. Luminance-voltage curves of OLEDs passivated by difference metal layer.........................................80
Fig. 4.23. Luminance-Power plots of OLEDs passivated by difference metal layer………...............................................81
Fig. 4.24. Efficiency-voltage curves of OLEDs passivated by difference metal layer…..…....................................82
Fig. 4.25. The lifetime of OLEDs passivated by difference metal layer at the condition(25 ℃, 40% RH)…….......................83
Fig. 4.26. I-V characteristics of OLEDs passivated by stacked passivation layer………….......................................84
Fig. 4.27. Luminance-voltage curves of OLEDs passivated by stacked passivation layer..............................................85
Fig. 4.28. Luminance-Power plots of OLEDs passivated by stacked passivation layer...…..........................................86
Fig. 4.29. Efficiency-voltage curves of OLEDs passivated by stacked passivation layer….............................................87
Fig. 4.30. The lifetime of OLEDs passivated by stacked passivation layer at the condition(25 ℃, 40% RH)……………………………………...88
Fig. 4.31. (a) Optical image without applied bias shows some bright points. (b) Electroluminescence image shows some dark spots around the bright points………………..............................89
Fig. 4.32. The radiated picture of the OLED device…………………….90

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