臺灣博碩士論文加值系統

本論文首先研製高效率黃色磷光有機發光二極體，利用雙極性之磷光主發光體材料EPH-31搭配黃色磷光客發光體材料EPY-01製作黃色磷光OLED元件，探討發光層厚度對於元件效率之影響，結果發現發光層厚度為60 nm時能使載子較為平衡，於20 mA/cm2下發光效率可達38.1 cd/A。接著搭配藍色螢光發光層欲製作螢磷混合式白色有機發光二極體元件，結果發現藍色與黃色發光層搭配無法製作出CIE值位於白光範圍內的有機發光二極體元件，改以橘紅色與藍色搭配製作白色有機發光二極體元件，利用高耐熱之雙極性螢光主發光體材料UBH-15搭配藍色螢光摻雜物EB-502作為藍光發光層，雙極性之磷光主發光體材料EPH-31搭配橘紅色磷光摻雜物(Os(bpftz)2(PPh2Me)2)作為橘紅光發光層，並比較另一雙極性之磷光主發光體材料26DczPPy，分別製作螢磷混合式白光有機發光二極體元件，對其光電特性進行探討，使用26DczPPy為主發光體時，因為雙發光層間的能階差異較大，載子能侷限在雙發光層介面處，使元件擁有良好的色穩定性，操作電壓從8 V到12 V，CIE色座標僅從(0.37,0.37)到(0.35,0.36)，但26DczPPy與摻雜物(Os(bpftz)2(PPh2Me)2)的HOMO能障過大(1.25 eV)，無法有效進行能量轉移，元件發光效率僅能達到12 cd/A。而使用EPH-31為主發光體結構時，發現電子傳輸層3TPYMB與發光層EPH-31的LUMO能階差異大(0.95 eV)，將導致電子不易注入發光層，因此將電子傳輸層共摻雜15 nm至發光層中，使電子能輕易進入發光層，於20 mA/cm2下，元件發光效率由15.1 cd/A提昇至17.2 cd/A，最後藉由加入少量濃度的黃色磷光摻雜，利用能量轉移機制，提高發光效率，20 mA/cm2下，CIE值為(0.41,0.43)，元件發光效率達到18 cd/A。

In this study, yellow phosphorescent organic light-emitting diode based on using phosphorescent bipolar host material (EPH-31) and phosphor dopant (EPY-01) was successfully fabricated at first. Through utilizing the thickness of emitting layer (EML), the charge carrier balance was achieved when thickness of EML was 60 nm. The current efficiency of 38.1 cd/A at 20 mA/cm2 can be obtained. After that, phosphorescent hybrid white organic light-emitting diode (HWOLED) was tried to fabricate by adding a fluorescent blue EML to previous yellow EML. But the HWOLED was unable located in the white light range of CIE coordinate. So it is necessary to change an orange dopant that aid to fabricate the HWOLED. Thermal stability bipolor fluorescent material (UBH-15) with fluorescent dopant (EB-502) as blue fluorescent EML(B-EML) along with (EPH-31) with orange dopant (Os(bpftz)2(PPh2Me)2 as orange phosphorescent EML(O-EML) was used. And then device based on this structure was compared with another bipolar phosphorescent host (26DczPPy). When using 26DczPPy as host material, the HWOLED obtained color stability due to barrier from each B-EML and O-EML energy band. So that carrier can be confine in the interface of two EMLs. Consequently, driving voltage increased from 8 V to 12 V, CIE coordinates only shifted from (0.37,0.37) to (0.35,0.36). There is a big barrier(1.25 eV) due to the difference of HOMO level between 26DczPPy and Os result in the difficultcy of energy-transfer. Performance only reached current efficiency of 12 cd/A. When using EPH-31 as host, the difference of LUMO energy level between EPH-31 and ETL(3TPYMB) was very large (0.95 eV), led electron moving hardly into EML. To solve this problem, co-doping 3TPYMB into EPH-31 structure was used, electron can move easily into EML. Current efficiency of device increased from15.1 cd/A to 17.2 cd/A. Finally, the HWOLED fabrication by utilizing energy-transfer mechanism, using low yellow doping concentration was shown the best current efficiency of 18 cd/A and CIE coordinate is (0.41,0.43).

摘要............................i
Abstract......................iii
誌謝............................v
表目錄........................viii
圖目錄..........................ix
第一章 緒論.......................1
1.1 有機發光二極體之發展歷程.........1
1.2 有機發光二極體之優點與展望.......1
1.3 研究動機......................3
第二章 文獻探討....................5
2.1 黃色磷光OLED元件...............5
2.2 白色螢磷OLED元件...............5
第三章 實驗方法與步驟...............8
3.1 實驗流程......................8
3.2 基板的清潔....................9
3.3 陽極的製備與前處理.............10
3.3.1 陽極製備過程................10
3.3.2 陽極前處理..................11
3.4 蒸鍍有機薄膜層.................12
3.4.1 有機材料之選用...............12
3.4.2 有機薄膜層蒸鍍系統與方式介紹....16
3.5 蒸鍍金屬薄膜層作為陰極...........17
3.6 元件量測......................19
3.7發光效率之計算..................20
第四章 結果與討論...................21
4.1 高效率黃色磷光有機發光二極體......21
4.1.1 不同發光層厚度對黃色磷光有機發光二極體光電特性之影響....21
4.2 白色螢磷混合式有機發光二極體.....26
4.2.1 不同磷光摻雜材料對白色螢磷混合式有機發光二極體光電特性之影響....26
4.2.2 不同藍色螢光發光層厚度對白色螢磷混合式有機發光二極體光電特性之影響....29
4.2.3 使用26DczPPy作為磷光主發光體材料製作白色螢磷混合式有機發光二極體元件....34
4.2.4 改變電子傳輸層材料對白色螢磷混合式有機發光二極體光電特性之影響....41
4.2.5 共摻雜電子傳輸層於磷光發光層對白色螢磷混合式有機發光二極體光電特性之影響....47
4.2.6 改變電子注入層材料對白色螢磷混合式有機發光二極體光電特性之影響....54
4.2.7 利用能量轉移機制提昇白色螢磷混合式有機發光二極體元件效率....60
第五章 結論....67
參考文獻....69
Extended Abstract....72
簡歷....75

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