市售人工照明富含藍光，不僅會汙染夜空、破壞生態，還會抑制人體褪黑激素的分泌，影響生理節律，故開發出不含藍光的低色溫OLED極為重要，為了提升低色溫OLED的元件表現，本研究藉由選用合適的供體（Donor）和受體（Acceptor），合成出激發複合體（Exciplex），使分子間有效能量轉移並提高效率；此外，對於有機發光二極體而言，濕式製程具有低成本、可快速連續製造等優點，因此本論文特別探討如何利用可濕式製作的激發複合體，來製作出高效率低色溫OLED元件。
本實驗以電洞傳輸材料3,6-Bis(N-carbazolyl)-N-phenylcarbazole（BCC-36）當作供體，電子傳輸材料2,4,6-Tris[3-(diphenylphosphinyl)phenyl]-1,3,5-triazine（PO-T2T）當作受體，形成激發複合體，並搭配客體綠光染料Bis(2-phenylquinoline) acetylacetonate iridium(III) [ Ir(ppy)2(acac) ]和紅光染料Tris(2-phenylquinoline) iridium(III) [ Ir(2-phq)3 ]，製作出高效率低色溫有機發光二極體；當綠光和紅光染料摻雜濃度分別為12.5 wt%、5 wt%時，在亮度100 cd/m2下，其色溫可達1975 K，能量效率為38.7 lm/W，電流效率為43.3 cd/A，外部量子效率為20.1 %，最大外部量子效率可達25.1 %，此最大外部量子效率為激發複合體濕式製程的世界紀錄。此低色溫OLED具有良好元件表現可歸因於：一、激發複合體的單重態和三重態能階差小（∆EST = 0.09 eV），使三重態激子可藉由環境熱能進行反向系統間跨越，成為單重激發態進而放光，二、供體和受體具有優異的電荷傳輸能力，能夠快速地引導電荷到達界面，三、良好的元件結構設計，使電荷有效在界面累積，四、激發複合體的光激發光譜與發光材料的吸收光譜重疊面積大，使激發複合體有效能量轉移（energy transfer）至發光染料。

Nowadays, artificial lighting is rich in blue light, which not only pollutes the night sky and destroys the ecology, but also inhibits the secretion of melatonin and affects the circadian rhythm. Therefore, it is extremely important to develop low color temperature OLEDs without blue emission. In order to improve the performance of low color temperature OLED devices, we selected an appropriate donor and acceptor to synthesize an exciplex to enable efficient energy transfer between molecules. In addition, the solution process has the advantages of low cost and rapid continuous manufacturing for organic light-emitting diodes. As a result, we specifically discusses how to use the solution-processed exciplex to fabricate high efficiency low color temperature OLED devices.
In this study, we form an exciplex system by using the hole transporting material 3,6-Bis(N-carbazolyl)-N-phenylcarbazole（BCC36）as the donor and the electron transporting material 2,4,6-Tris[3-(diphenylphosphinyl)phenyl]-1,3,5-triazine （PO-T2T）as the acceptor. To produce high efficiency low color temperature organic light emitting diodes, the exciplex is doped with green phosphorescent emitter Bis(2-phenylquinoline) acetylacetonate iridium(III) [ Ir(ppy)2(acac) ] and red phosphorescent emitter Tris(2-phenylquinoline) iridium(III) [ Ir(2-phq)3 ]. When the doping concentrations of the green and red dyes are 12.5 wt% and 5 wt% respectively, the color temperature can be reduced to 1975 K, the power efficiency is 38.7 lm/W, the current efficiency is 43.3 cd/A, and the external quantum efficiency is 20.1% at a luminance of 100 cd/m2. The maximum external quantum efficiency can reach to 25.1% which is the world record for the exciplex in solution process. This low color temperature OLED which has good device performance can be attributed to the following : (1) The singlet-triplet gap（∆EST = 0.09 eV）of the exciplex system is small, so the system can convert triplets into singlets and achieve reverse intersystem crossing (RISC) by the environmental thermal energy；(2) The donor and acceptor have excellent charge transport capabilities and can quickly transport the charge to the interface；(3) The good device structure design allows the charge to accumulate effectively at the interface；(4) The photoluminescent spectrum of the exciplex and the absorption spectrum of the emitters have large overlapping area, so that the exciplex can effectively transfer energy to the emitters.

摘要---I
ABSTRACT---III
獻---V
致謝---VI
目錄---X
表目錄---XIV
圖目錄---XV
壹、緒論---1
貳、文獻回顧---3
2-1、OLED的發光原理---3
2-2、OLED的能量傳遞機制---7
2-3、OLED的基本結構---10
2-4、OLED的元件效率---10
2-5、OLED材料之發展---12
2-5-1、陽極材料---12
2-5-2、電洞注入材料---12
2-5-3、電洞傳輸材料---13
2-5-4、電子傳輸材料---14
2-5-5、電子注入材料---14
2-5-6、陰極材料---15
參、激發複合體有機發光二極體---16
3-1、激發複合體有機發光二極體介紹---16
3-2、激發複合體形成機制及條件---17
3-3、激發複合體之功能與優點---18
3-4、用於單色OLED之激發複合物主體---19
3-4-1、高效率紅光OLEDs---19
3-4-2、高效率綠光OLEDs---20
3-4-3、高效率藍光OLEDs---22
3-5、激發複合體有機發光二極體重要文獻回顧---24
3-6、提高激發複合體元件表現之方法---28
肆、實驗方法---29
4-1、本研究使用之材料---29
4-1-1、材料之功能、全名與簡稱---29
4-1-2、材料之化學結構式---31
4-2、材料特性量測儀器之原理與方法---34
4-2-1、紫外線-可見光吸收光譜(Ultraviolet visble absorption, UV-Vis)之量測---34
4-2-2、光激發光譜(Photoluminescent spectrum)之量測---34
4-2-3、時間解析光激發光譜(Time-Resolved Photoluminescence
，TRPL)之量測---35
4-3、元件設計與製備---35
4-3-1元件電路設計---35
4-3-2 ITO基材清潔---36
4-3-3旋轉塗佈電洞注入層---37
4-3-4旋轉塗佈發光層---37
4-3-5真空熱蒸鍍製程---38
4-3-6成膜鍍率測定---39
4-3-7有機層和無機層之製備---39
4-4、元件之量測及發光效率之計算---40
伍、結果與討論---42
5-1、材料之光物理特性---42
5-2-1、紫外線-可見光吸收光譜及光激發光譜---43
5-2-2、時間解析光激發光譜---46
5-2、元件結構---47
5-3、供受體濃度對元件的影響---48
5-4、不同發光機制對元件的影響---50
5-5、高效率低色溫有機發光二極體---56
陸、結論---66
柒、參考資料---68
附錄、個人著作目錄---73
(A) 研討會論文---73
(B) 得獎紀錄---73

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