有機發光二極體 (Organic Light Emitting Diode, OLED)，因其具有自發光、無汞、輕、薄、省電、可撓等優點，可應用在顯示與照明技術上，而對於製作高品質RGBY顯示器和生理友善的低色溫照明光源，高效率黃光元件扮演不可或缺的角色；此外，搭配濕式製程，可使產品具有低成本、可大面積連續滾印(roll-to-roll)等優點。綜合以上考量，本實驗選用一系列新穎主體的GB系列(GB-204、GB-213、GB-221)搭配磷光黃光染料bis(4-phenylthieno[3,2-c]pyridinato-N,C 2’)acetylacetonate iridium(III) (PO-01)製作濕式 OLED元件；實驗結果發現，以GB-221表現最佳，亮度 100 cd m-2 的情況下，其電流效率為30.9 cd A-1，能量效率27.1 lm W-1；亮度 1,000 cd m-2 的情況下，其電流效率為25.5 cd A-1，能量效率 17.8 lm W-1；亮度 10,000 cd m-2 的情況下，其電流效率為 13 cd A-1，能量效率6 lm W-1，最大亮度可達20,000 cd m-2。此元件的好表現可歸因於：一、主客體間能量傳遞良好，使在主體產生的激子能順利轉移至客體。二、合適的主客體能階搭配，使得激子可在主客體中順利產生。

Organic light emitting diodes (OLEDs) can be applied to displays and lighting due to their promising characteristics such as being self-luminous, mercury free, light, thin, and flexible. And, for RGBY display technology and fabricating physiologically-friendly low color temperature lighting source, yellow emission is the most crucial one. On the other hand, wet-process can achieve roll-to-roll production and low-cost probability. For these reasons, we study in this thesis yellow OLEDs with a series of solution-processable benzimidazole-branched host materials, GB-204, GB-213, GB-221. By coupling PO-01 with the proper host GB-221, the yellow device shows current efficiency of 30.9 cd A-1 and an efficacy of 27.1 lm W-1 at 100 cdm-2, 25.5 cd A-1 and 17.8 lm W-1 at 1,000 cd m-2, 13 cd A-1 and 6 lm W-1 at 10,000 cd m-2 and a max brightness of 20,000 cd m-2. The high efficiency may be attributed to the effective host-to-guest energy transfer as well as the paired host and guest energy-levels which allows excitons to generate both on the host and guest.

摘要 I
Abstract II
誌謝 III
目錄 VI
表目錄 IX
圖目錄 X
壹、緒論 1
貳、文獻回顧 4
2-2 有機發光二極體之發光原理 20
2-3、能量傳遞機制 25
2-4、光色定義 29
2-5、出光機制 30
2-6 有機發光二極體主體材料之發展 32
2-6-1 電洞傳輸性主體(HT-type host) 33
2-6-2 電子傳輸性主體(ET-type host) 41
2-6-3 雙極性主體(bipolar host) 51
2-7濕式製作之黃光有機發光二極體發展 66
參、實驗方法 69
3-1、材料 69
3-1-1、材料之功能、全名及簡稱 70
3-1-2、本研究所使用有機材料之化學結構式 71
3-2、材料特性量測之儀器設備與方法 74
3-3、元件設計及製備 76
3-3-1元件電路設計 76
3-3-2 ITO基材清潔與前處理 77
3-3-3、旋轉塗佈電洞傳輸層 77
3-3-4、發光層之製備 78
3-3-5、蒸鍍裝置 78
3-3-6 蒸鍍速率之測定 79
3-3-7 電子傳輸層之製備 80
3-3-8 無機層之製備 80
3-4 元件光電特性量測 80
肆、結果與討論 82
4-1新穎主體材料特性 82
4-2、黃光元件 85
4-2-1、元件能階結構 85
4-2-2、主體材料對元件的影響 86
4-2-3、客體染料濃度的影響 91
4-3、其他光色(紅、綠、藍)元件 95
4-3-1、元件能階結構 95
4-3-2、主體材料對元件的影響 96
伍、結論 101
陸、參考文獻 103
 

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