臺灣博碩士論文加值系統

研究中利用高電洞遷移率的主發光體材料(TCTA)與電子遷移率較佳的電子傳輸層材料(TmPyPB)，以共摻雜方式來製作藍光OLED元件之混合式主發光體結構(mixed-host structure)，提升電荷載子注入到發光層的效率，降低元件驅動電壓，並提升元件發光效率，利用CsF取代LiF作為電子注入層與調整摻雜的濃度比例(1:1)至元件最佳化後，藍光元件於亮度1000 cd/m2時，驅動電壓降為4.4 V，電流效率提升到34.7 cd/A，功率效率增加至24.8 lm/W。研究亦利用將橘紅光材料(Os(bpftz)2(PPh2Me)2)摻入最佳化藍光元件內的不同位置，可製作高效率雙波段白光元件，實驗結果顯示，當Os與FIrpic共摻雜於單發光層(TCTA：TmPyPB)時，於亮度1000 cd/m2時，元件驅動電壓為4.6 V，電流效率由34.7 cd/A提升到37.4 cd/A，功率效率由24.8 lm/W增加至25.5 lm/W。實驗最後於混合式主發光體結構中，共摻雜Os(bpftz)2(PPh2Me)2、Ir(ppy)3與FIrpic，並調整三色摻雜物之摻雜區位置以製作三波段白色磷光OLED元件，當發光層結構為RGB共摻雜時，可有效改善元件色偏(color-shift)之問題，其元件搭配BEF，於發光亮度1000 cd/m2下，電流效率為43.8 cd/A，功率效率為32 lm/W，且最大電流效率可達45.4 cd/A及功率效率為35.7 lm/W，且當元件操作電壓由4 V至8V，其1931 CIEx,y座標CIE值由(0.346, 0.374)僅偏移至(0.316, 0.364)。

In this study, the hole transport-type host material (TCTA) was incorporated with the electron transport material (TmPyPB) as a mixed-host structure to future improving the injection of charge carriers and reduce the driving voltage of the phosphorescent organic light-emitting diodes (PHOLEDs). The charge carrier balance of PHOLED was achieved by using CsF as electron injection layer and optimizing the doping ratio of TCTA and TmPyPB (1:1). At a luminance of 1000 cd/m2, highly efficiency blue PHOLED shown the best yield of 34.7 cd/A and power efficiency of 24.8 lm/W. Furthermore, a highly efficiency two-components system white PHOLED can be obtained by doping Os(bpftz)2(PPh2Me)2 into the emitting layer of optimizing blue PHOLED. The driving voltage of 4.6V, yield of 37.4 cd/A, and power efficiency of 25.5 lm/W at a luminance of 1000 cd/m2 can be obtained. Finally, a high efficiency three-components system white PHOLED was fabricated by co-doping three phosphor dopant (Os(bpftz)2(PPh2Me)2, Ir(ppy)3 and FIrpic) into mixed-host (TCTA:TmPyPB) structure and optimizing the doping region and each layer thickness. From the experimental results, the optimal white PHOLED showed the driving voltage of 4.4 V, yield of 34 cd/A, and power efficiency of 24.2 lm/W at a luminance of 1000 cd/m2 can be observed. Furthermore, the efficiencies can be increased to 43.8 cd/A and 32 lm/W by attaching an outcoupling brightness enhancement film (BEF) onto glass substrate and the CIE coordinate exhibited blue-shift from (0.346, 0.374) to (0.316, 0.364) under different driving voltages.

摘要......................................................i
Abstract.................................................ii
致謝....................................................iii
目錄.....................................................iv
圖目錄.................................................viii
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 有機發光二極體之發光理論與機制......................6
2.1 有機發光元件結構與發光機制.............................6
2.1.1 有機發光二極體元件之基本結構.........................6
2.1.2 有機發光二極體元件之發光機制介紹.....................9
2.2 螢光與磷光有機發光二極體發光原理......................10
2.3 有機發光二極體元件之能量轉移機制......................11
2.3.1 有機材料之吸收與放射................................11
2.3.2 能量轉移機制介紹....................................11
2.3.3 載子捕捉機制介紹....................................13
2.3.4 載子遷移率介紹......................................13
2.4 空間限制電荷與注入限制電荷............................14
2.5 元件之結構與文獻探討..................................15
第三章 實驗方法與步驟.....................................23
3.1 實驗流程..............................................23
3.2 基板的清潔............................................23
3.3 陽極的製備與前處理....................................24
3.3.1 陽極製備過程........................................24
3.3.2 陽極前處理..........................................26
3.4 蒸鍍有機薄膜層........................................26
3.4.1 元件有機材料之選用..................................26
3.4.2 有機薄膜層蒸鍍系統與方式介紹........................28
3.5 蒸鍍金屬薄膜層作為陰極................................28
3.6 元件量測..............................................29
3.7發光效率之計算.........................................30
第四章 結果與討論.........................................36
4.1 藍色磷光有機發光二極體................................36
4.1.1 比較不同的磷光主發光體材料(TCTA與mCP)對藍色磷光有機發光二極體(Blue PHOLED)光電特性之影響.......................36
4.1.2 利用具雙極性之主發光體材料26DCzPPy，製作藍色磷光有機發光二極體(Blue PHOLED).....................................38
4.2 不同主發光體材料對白色磷光有機發光二極體光電特性之影響........................................................40
4.3 共摻雜電子傳輸層材料TmPyPB於發光層作為白色磷光有機發光二極體之混合式主發光體結構(mixed-host structure)，以提升發光效率........................................................44
4.3.1 將電子傳輸層材料(TmPyPB)與緩衝層兼發光層材料(TCTA)共摻雜作為混合式主發光體結構以製作白色磷光有機發光二極體......45
4.3.2 調整本質中間層之厚度與混合式主發光體結構之摻雜比例對白色磷光有機發光二極體光電特性之影響........................47
4.4 改變電子注入層並調整共摻雜電子傳輸層材料於發光層之藍光磷光有機發光二極體特性之影響................................48
4.5 不同橘紅光摻雜物(Os)摻雜區域對白色磷光有機二極體光電特性之影響....................................................51
4.6 調整R、G、B三色摻雜物摻雜區域對白色磷光有機發光二極體光電特性之影響..............................................53
第五章 結論...............................................93
參考文獻..................................................95
Extended Abstract
簡歷

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