臺灣博碩士論文加值系統

本論文以溶液式製程製作1 cm ⅹ 1 cm藍色螢光有機發光二極體，利用ITO / MADN：13%UBD-07 / Al為基本結構分別加入電洞注入層PEDOT及電子注入層LiF，進而推論出電洞數目遠大於電子數目，隨後進行了一連串之元件優化。首先將A-2元件加入洞阻擋層TPBi增加電子數目並阻擋電洞於發光層，當厚度20 nm時，在定電壓8V下效率為0.52 cd/A，接著調變ITO UV Ozone照射秒數限制電洞數目，當秒數為100秒時限制電洞效果較佳，在定電壓8V下效率為0.55 cd/A，接著，調變電子注入層LiF厚度觀察其幫助電子注入效果，當厚度為0.5 nm時，在定電壓8V下效率為0.78 cd/A。
為了提升元件壽命加入電洞注入層PEDOT減少尖端效應造成短路機率，此時定電壓8V下效率為0.64 cd/A，而壽命為121分鐘。由於PEDOT加入將使電洞數量增加，為了避免電子、電洞過於失衡而加入電子傳輸層Alq3，當TPBi/Alq3.厚度為10 nm /15 nm時，在定電壓8V下效率為1.29 cd/A，而壽命提升至252.25分鐘。為了觀察吸溼劑除水氣效果，利用F-2元件結構比較有無貼吸溼劑之壽命差異，然而經實驗結果得知，有貼吸溼劑之元件壽命僅提升22.75分鐘，推測其原因為元件運送過程接觸水、氧氣導致有機層劣化。接著，將發光層厚度調變為2倍，增加電子、電洞複合機率，當發光層厚度為90 nm並採用熱蒸鍍法製作時，在定電壓8V下效率為3.23 cd/A，而壽命提升至482.25分鐘。
最後，將電洞注入層PEDOT厚度調變為220 nm時，在定電壓8V下效率為3.86 cd/A，而壽命提升至529分鐘。由元件中心溫度分佈圖得知，元件溫度變化隨著電流從5 mA調高至40 mA，其溫度也漸漸由30.1℃提高至57.2℃，並在到達50 mA時超過元件可承受之電壓範圍導致溫度大幅衰減回35.9℃。

This paper has made use of solution process to produce blue fluorescent organic light-emitting diodes, and its light-emitting size measures 1 cm x 1 cm. Using ITO/MADN：13%UBD-07/Al as the basic structure, the hole injection layer PEDOT and the electron injection layer LiF are added respectively, and it is inferred that the number of holes is much more than electrons, and then a series of devices optimization is performed. First, the device of A-2 is added to the hole blocking layer TPBi to increase the number of electrons and block hole in EML. When the thickness is 20nm , the efficiency is 0.52 cd/A at the constant voltage of 8V. And then in order to limit holes, adjusting UV Ozone irradiation seconds. When the number of seconds is 100 seconds, the effect is the best. The efficiency is 0.55 cd/A at constant voltage of 8V. And then the thickness of the electron injection layer LiF is adjusted and observed to help the electron injection effect. When the thickness is 0.5 nm, the efficiency is 0.78 cd/A at the constant voltage of 8V.
In order to improve the lifetime of devices, the hole injection layer PEDOT is added to reduce the probability of point effect. At this time, the efficiency is 0.64 cd/A at the constant voltage of 8V, and the lifetime is 121 minutes. Since the PEDOT addition will increase the number of holes, the electron transport layer Alq3 is added to avoid excessive imbalance of electrons and holes When the thickness of TPBi/Alq3 is 10 nm/15 nm, the efficiency is 1.29 cd/A at the constant voltage of 8V, and the lifetime is increased to 252.25 minutes.
In order to observe the effect of the getter in removing water vapor, the device structure of A-2 is used to compare the lifetime difference of the getter. However, the experimental results show that the lifetime of the device with the getter is only increased by 22.75 minutes, which is presumed to be due to the contact of water and oxygen in the device transport process.
And then, the thickness of the luminance layer is adjusted to two times to increase the probability of electrons and holes combination. When thickness of the luminance layer is 90 nm and is made by thermal evaporation, the efficiency is 3.23 cd/A at the constant voltage of 8V, and the lifetime is improved to 482.25 minutes. Finally, when the hole injection layer PEDOT is adjusted to 220 nm, and the efficiency is 3.86 cd/A at the constant voltage of 8V, and the lifetime is increased to 529 minutes.
From the device temperature distribution map, the device temperature change increases from 5 mA to 40 mA, and its temperature gradually increases from 30.1 °C to 57.2 °C. When it reaches 50 mA, it exceeds the voltage range that the device can’t withstand, causing the temperature to decay significantly back to 35.9 °C.

摘要....................................i
Abstract...............................ii
誌謝...................................iv
目錄....................................v
表目錄................................vii
圖目錄...............................viii
第一章、緒論............................1
1.1有機發光二極體簡介....................1
1.2研究動機.............................2
第二章、有機發光二極體原理及文獻探討......3
2.1有機發光二極體原理....................3
有機發光二極體發光機制...................3
有機發光二極體各層結構介紹...............6
2.2有機發光二極體文獻探討................8
第三章、實驗方法與步驟..................11
3.1實驗流程............................11
3.2陽極的製備..........................12
雷雕圖案化.............................12
基板清洗 ..............................13
ITO基板表面處理........................14
3.3溶液式旋轉塗佈有機層.................16
溶液式有機發光二極體製作流程.............16
元件有機材料之選用......................18
3.4熱蒸鍍有機層........................19
熱蒸鍍有機層操作流程....................19
熱蒸鍍有機層之材料選用..................22
3.5金屬蒸鍍陰極........................23
3.6元件封裝............................25
3.7元件特性量測........................27
光電特性曲線量測.......................27
壽命量測..............................28
第四章、結果與討論.....................29
4.1藍色有機發光二極體之電流研究.........29
加入注入層之電流比較...................29
加入電洞阻擋層之光電特性比較............31
調變ITO UV Ozone照射秒數之光電特性比較..34
調變電子注入層LiF厚度之光電特性比較......37
4.2藍色有機發光二極體之壽命延長.........40
加入電洞注入層之光電特性比較............40
加入電子傳輸層之光電特性比較............44
調變發光層厚度之光電特性影響............49
電洞注入層增厚之光電特性影響............53
4.3藍色有機發光二極體之熱效應研究.......60
第五章、結論..........................67
參考文獻..............................69
Extended Abstract....................72

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