臺灣博碩士論文加值系統

　　有機發光二極體（organic light-emitting diode, OLED）為極具潛力的照明產品，目前量產多採用真空蒸鍍製程，在量產上受限於面積與製程成本等問題，因此學界與業界致力研究溼式塗佈之OLED製程，使其元件表現及價格符合市場需求。
　　本研究主要目的為探討影響溼式製程OLED元件表現之因素，其指標包含效率與壽命。本研究以先前本實驗室建立的綠光OLED材料與元件結構為基礎，製作發光面積為0.25 cm2之三有機層綠光OLED元件，以旋轉塗佈法製備三有機層，由效率與壽命判斷較適化製程條件，同時確認影響元件表現的顯著因子，在亮度3000 cd/m2下功率效率達到6 lm/W，操作電壓約8 V，以此作為起始亮度所測得之壽命由低於0.5 hr上升至超過20 hr。元件衰退之關鍵機制為材料的成膜狀態，因此以不同方式觀測膜面與膜層內部的形態，初步建立有機薄膜的分析方法。本研究另行測試四有機層OLED元件之表現，以真空蒸鍍法製備電子傳輸層，確認其獨立堆疊於發光層上對於元件效率與壽命的影響顯著性，亮度3000 cd/m2下功率效率達11 V以上，操作電壓則低於7 V；起始亮度1000 cd/m2所測得之壽命超過260 hr。

Organic light-emitting diodes (OLEDs) have great potential on lighting application. OLED panels has been commercialized with high cost partly due to the vacuum deposition process. In order to reduce the process cost, solution process is expected to be applied on OLED fabrication. Therefore, researches on solution-processed OLEDs have received extensive attention to meet the market demands.
The main purpose of this research is to analyze the factors that would influence the performance, including efficiency and lifetime, of OLED lighting devices. The green phosphorent OLED devices with 0.25 cm2 emissive area were fabricated and the organic layers except electron transport layer were produced by spin coating as test samples.
In the OLED devices with three organic layers, the power efficiency at the luminance of 3000 cd/m2 reached 6 lm/W with operating voltage at about 8 V. The lifetime with the initial luminance of 3000 cd/m2 is increased from less than 0.5 hr to more than 20 hr. The morphology of the organic thin films was considered to be the key factor to influence the device performance, so the analysis on the film surface and the whole layer was carried out. In the devices with four organic layers, the power efficiency at the luminance of 3000 cd/m2 reached 11 lm/W with operating voltage less than 7 V. The lifetime with the initial luminance of 1000 cd/m2 is increased to more than 260 hr.

摘要 i
目錄 iii
圖目錄 vi
表目錄 x
第1章 緒論 1
1.1 前言 1
1.2 研究動機與目的 2
第2章 文獻回顧 4
2.1 有機發光二極體簡介 4
2.1.1 OLED發光原理 6
2.1.2 OLED元件結構 13
2.1.3 OLED製程技術 15
2.1.4 OLED應用 19
2.2 影響有機發光二極體壽命因素 20
2.2.1 非本質劣化因素 23
2.2.2 本質劣化因素 25
2.2.3 改善有機發光二極體壽命方法 31
2.3 影響有機發光二極體效率因素 33
第3章 實驗材料與研究方法 35
3.1 材料與藥品 35
3.2 設備與儀器 43
3.3 元件電路設計 46
3.4 基材清洗 47
3.5 元件製作步驟 48
3.6 元件效率與壽命量測 49
3.7 膜厚量測與薄膜分析 51
第4章 結果與討論 52
4.1 選擇電子傳輸材料 52
4.2 探討較適化發光層材料比例 59
4.3 探討較適化膜厚 63
4.3.1 LiF膜厚較適化 64
4.3.2 四層膜厚較適化 68
4.4 探討較適化發光層退火條件 81
4.4.1 較適化退火溫度 82
4.4.2 較適化退火時間 93
4.5 探討四有機層結構之元件表現 96
4.6 有機薄膜分析 105
4.6.1 膜面分析 105
4.6.2 膜層分析 108
第5章 結論 116
參考文獻 118

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