有機白光二極體 (WOLEDs) 被認為是下一世代的固態照明與大面積發光顯示器，現今 WOLEDs 使用磷光客體，而能使用三重態激子，使得磷光系統的白光元件 ( PHWOLEDs )擁有極高的效率；然而高效率 PHWOLEDs 都為全蒸鍍製作，蒸鍍製程因成本高而不利於工業化，所以許多團隊投入生產成本較低的濕式製程。小分子主體因合成、純化簡單，而可得到高純度的材料，此外小分子主體的三重態高且載子傳輸能力好，因此有許多團隊研究在維持元件效能下將蒸鍍製程的小分子元件濕式化。近年許多團隊研究TADF客體材料，TADF 材料因三重態與單重態間能量差小 ( S1-T1<0.1 eV )，三重態的激子能吸收室溫的熱能而被激發至單重態，所以TADF系統也能使用三重態激子，因此 TADF 元件的內部量子效率最大可達 100 %，磷光客體價格昂貴且為對環境有危害的重金屬，而不利於工業化，因此以價格便宜、無毒的TADF客體取代磷光客體為現今 WOLED s發展的趨勢。因此本論首先研究製作高效能的藍、白磷光元件，接著以TADF客體取代磷光客體來製作低成本的藍、白光元件。

本論文實驗成果分為 磷光系統 與 TADF 系統，在磷光系統我們使用bipolar主體 26DCzPPy摻雜電洞傳輸材料 TCTA ，並摻雜 10 wt% 藍磷光客體 Firpic，以結構 ITO/PEDOT: PSS/26DCzPPy:TCTA =8:2 (wt%:wt%)+10 wt% Firpic/TmPyPB/CsF/Al 製作藍光元件，它的元件的表現BMax=45898 cd/m2、CEMax=38.9 cd/A、PEMax=22.6 lm/W、EQEMax=19.34 %為現今
最佳的濕式製作的藍光元件之一。此外我們在藍光元件的發光層中摻入黃磷光PO-01 或 紅磷光 Ir(dpmM)PQ2 製作白光元件，以黃磷光製作白光的元件表現為 BMax=73547 cd/m2、CEMax=38.8 cd/A、PEMax=23.2 lm/W、CIE(0.33,0.44)，而以紅磷光製作白光元件表現 BMax=50521 cd/m2、CEMax=26.2 cd/A、PEMax=15.2 lm/W、CIE(0.33,0.37)。

在 TADF 系統中，以 TADF 作為客體取代磷光客體。由螢光光譜得知，DMAC-TRZ的最大放光波長 ( λMax )為 495 nm與 Firpic λMax=473 nm、500 nm相比略為紅移，因此以 26DCzPPy:TCTA=8:2 (wt%:wt%)作為DMAC-TRZ元件的主體應該要有好的元件效率。我們以結構 ITO / PEDOT : PSS / 90 wt% 26DCzPPy: TCTA=8:2( wt%:wt% )+10 wt% DMAC-TRZ
/TmPyPB/CsF/Al製作 TADF 藍光元件，它的元件表現 BMax=57586 cd/m2、CEMax=35.3 cd/A、PEMax=21.4 lm/W、EQEMax=14.1 %遠超過現今濕式製程的TADF藍光元件。此外我們在藍光元件的發光層中摻入紅磷光Ir(dpm)PQ2來製作白光元件，它的元件的表現 BMax=43594 cd/m2、CEMax=28.8 cd/A、PEMAX=18.1 lm/W、CIE(0.38,0.44)，此元件亮度遠超過蒸鍍製程的 TADF 白光元件(~10000 cd/m2)，且也為文獻中第一個以濕式製作的TADF白光元件。

White organic light-emitting diodes ( WOLEDs ) are expected to be used as next generation solid lighting and large display application, in which phosphorescent emitters are included for taking the advantage of harvesting triplet excitons and therefore leading to high device performance. However, the highly efficient phosphorescent WOLED ( PHWOLED ) is always fabricated by thermal vacuum deposition method which is a high-cost process. Attempts to fabricate the WOLED by low-cost wet processes have been made. Small molecular materials seem to be good candidates for solution-processed PHOLEDs because of their high purity, high triplet energy, and high carrier transport capability. Therefore, many investigations on how to produce highly efficient solution-processed WOLED with small molecular emitters have been attempted and reported that its performance in some cases can be as high as those by vacuum deposition. Recently, thermally activated delay fluorescence ( TADF ) emitters have been found as attractive alternative emitters, because they can harvest both singlet and triplet excitons and therefore give highly efficient device performance. TADF materials possess small energy gap between singlet and triplet states ( ΔEST<0.1 eV ) that allows to an efficient reverse intersystem crossing for converting triplet excitons to singlet excitons after absorbing thermal energy at room temperature.Thus, TADF OLEDs are able to reach a maximum internal quantum efficiency (IQE) of 100 %. Phosphors containing noble-metal are expensive and might be harmful to the environment, while TADF emitters are not only cheaper but also more environment-friendly than phosphors; so it is a new tendency of development WOLEDs by using TADF emitters to replace phosphors. Therefore, the present study focuses on how to produce highly efficient blue and white light-emitting diodes and then using TADF emitters to replace phosphors.

Two parts of the research results included in this thesis are PHOLEDs and TADF OLEDs. In the PHOLEDs system, we use the bipolar molecule 2,6-bis(3-(9H-Carbazol-9-yl) phenyl) pyridine (26DCzPPy) doped 20 weight percent (wt %) of the hole transport materials Tris(4-carbazoyl-9-ylphenyl)amine(TCTA) as host and 10 wt% iridium(III) bis[2-(4,6- difluorophenyl)-pyridinato- C2,N](picolinato (Firpic) as guest. The device ITO /PEDOT : PSS/ 26DCzPPy : TCTA=8:2 (wt%: wt%)+ 10 wt% Firpic/
TmPyPB /CsF/Al achieves excellent performance with the maximum Brightness (BMax) 45898 cd/m2, maximum power efficiency (PEMax) 22.6 lm/W, maximum current efficiency (CEMax) 38.9 cd/A [equivalent to the external quantum efficiency (EQE) 19.34%]. This device performance is one of the best solution-processed blue OLEDs. For WOLEDs, we use yellow phosphor iridium(III) bis(4-phenylthieno[3,2-c]pyridinato-N,C2')acetylacetonate(PO-01) or red phosphor iridium(III) bis-(2- phenylquinoly -N,C2′)dipivaloyl-methane [Ir(dpm)PQ2] to dope into the blue emitting layer for fabricating PHOWOLEDs. The performance of the PHWOLED using PO-01 is BMax 73547 cd/m2, CEMax 38.8 cd/A, PEMAX 23.2 lm/W, and CIE Coordinates of (0.33, 0.44); and that using Ir(dpm)PQ2 is BMax 50521 cd/m2, CEMax 26.2cd/A , PEMax 15.2 lm/W, and CIE (0.33,0.37).

In the TADF OLEDs system, TADF emitter is used to replace phosphor as guest. From the Photoluminescence (PL) spectrum, since
9,9-dimethyl-9,10-dihydroacridine-2,4,6-triphenyl-1,3,5-triazine (DMAC-TRZ) PL (λMax) 495nm comparing to those of Firpic (473, 500 nm) is slightly red shift, so using 26DCzPPy: TCTA =8:2(wt%: wt%) as host is also suitable for DMAC-TRZ to achieve high device performance. The device ITO/PEDOT: PSS/26DCzPPy: TCTA=8:2(wt%:wt%) +10 wt% DMAC-TRZ /TmPyPB / CsF/Al, achieves the excellent performance BMax 57586 cd/m2, CEMax 35.3 cd/A , PEMax 21.4 lm/W , EQEMax 14.1%, which is the best among the reported solution-processed TADF blue OLEDs. For the TADF WOLEDs by doping red phosphor Ir(dpm)PQ2 to the blue emitting layer of the TADF OLED; and the performance of TADF WOLED is BMax 43594 cd/m2, CEMax 28.8 cd/A, PEMax 18.1 lm/W, and CIE (0.38, 0.44), and the maximum brightness is better than that of vacuum deposited TADF WOLEDs (～10000 cd/m2). This is the first report on solution-processed TADF WOLED.

目錄
第一章 緒論 1
1-1 前言 1
1-2磷光放光機制[1] 2
1-3 金屬半導體理論[2] 4
1-3-1 界面接合 4
1-3-2 電流傳遞過程 5
1-4 高分子發光二極體的研究 6
1-4-1 電荷注入/傳遞的機制 9
1-4-2 電子的注入 11
1-4-3 電洞的注入 13
1-4-4 發光層載子的傳遞特性 15
第二章文獻回顧 18
2-1小分子濕式藍、白磷光元件 18
2-2小分子濕式藍光TADF元件 24
2-3 蒸鍍製層的TADF白光元件 29
2-4文獻分析 36
第三章實驗方法 38
3-1藥品 38
3-2儀器設備 39
3-3 元件的製作 39
3-3-1高分子發光二極體元件製作 39
3-3-2 單一載子元件製作 40
3-3-3元件特性之量測 40
第四章磷光系統藍、白發光元件 42
4-1前言 42
4-2元件設計概念 43
4-3使用雙極性小分子BCPO或26DCzPPy作為主體 46
4-4於主體摻雜電洞傳輸材料 49
4-5混摻黃磷光小分子製作白光元件 53
4-6混摻紅磷光小分子製作白光元件 56
4-7不同電場下白光光色穩定性探討 59
4-8結論 61
第五章 TADF系統藍、白發光元件 62
5-1 前言 62
5-2元件設計概念 63
5-3使用交聯非共轭高分子PVK和階梯式共轭高分子作為電洞傳輸層 66
5-3-1以UV-Vis吸收度測試傳輸層的抗溶劑效果 66
5-3-2使用電洞傳輸層的元件表現 68
5-4主體摻雜電洞傳輸材料 70
5-5調控發光層TCTA摻雜比例 74
5-6調控發光層客體的DMAC-TRZ摻雜濃度 76
5-7調控發光層膜厚 78
5-8PEDOT:PSS摻雜PFI以改變HOMO的能階 81
5-9藍光元件EL光譜探討 84
5-9-1不同主體的藍光元件EL光譜探討 84
5-9-2不同濃度的客體DMAC-TRZ的藍光元件EL光譜探討 85
5-10混摻紅螢光、磷光小分子製作白光元件 86
5-10-1混摻紅磷光小分子製作白光元件 87
5-10-1混摻紅螢光小分子製作白光元件 90
5-11白光元件EL光譜探討 93
5-12結論…………………………………………………………………95
第六章 參考文獻 96





















圖目錄
Figure1-1. Schematic energy-level alignment of the singlet-excited states (S1), triplet-excited states (T1) and ground states (S0), as well as the energy transfer and light-emission processes in host dopant systems. 2
Figure 1-2 .Schematic representation of Förster energy transfer (a) and Dexter energy transfer (b); energy transfer (c) and charge trapping (d)alignment for dopant emission in host-dopant systems. 3
Figure 1-3.Barriers for semiconductors of different types and work functions. n-type:(a) Φm> Φs(Schottky); (b)Φm<Φs(Ohmic) p-type: (c) Φm<Φs(Schottky); (d)Φm> Φs(Ohmic). 6
Figure 1-4. Schematic structure of polymer LED and carrier transport in PLED. 7
Figure 1-5. Band diagram of singlet exciton formation in (a) PL and (b) EL process. 8
Figure 1-6. Schematic structure of ITO/PPV/PBD: PMMA/Ca and carrier transport in this device. 12
Figure1-7.The structure of (A) OC1C10-PPV, (B) OC1C10-PPV, (C)OC10C10-PPV, (D)OC1C5-PPV. 16
Figure 1-8.Hole mobility of spin-coated PFO film measured from time-of-flight technique at 300K. 17
Figure 1-9. Hole mobility for an aligned quenched PFO film (filled circles) and for a spin-coated PFO film (open circles) measured from time-of-flight technique at room temperature. 17
Figure2-1.元件各層材料的能階圖。 19
Figure2-2.元件各層材料的化學結構。 19
Figure2-3. 發光層摻雜不同TAPC濃度下，(a)元件結ITO/PEDOT:PSS/ TCTA+ TAPC+Firpic /TmPyPB/LiF/Al的電流密度對電壓圖、(b) Hole-only元件:ITO/PEDOT:PSS/TCTA+TAPC+Firpic/MoO3/Al的電流密度對電壓圖。 20
Figure 2-4. 主體26DCzPPy的化學結構圖。 21
Figure2-5.發光層為(a)26DCzPPy+TAPC+Firpic(b)TCTA+TAPC+Firpic，在元件結構ITO/PEDOT:PS/ EML/ TmPyPB/LiF/Al的EQE對電流密度圖。 21
Figure2-6.主體為Bipolar、unipolar的再結合區示意圖。 21
Figure 2-7. 主體TCPy與藍磷光Ir(Fppy)3的化學結構。 22
Figure2-8. PVK與PMA產生氧化還原反應機制圖。 22
Figure 2-9.元件所使用材料的化學結構圖。 23
Figure2-10. chlorobenzene或tetrahydrofuran 作為發光層溶劑，在(a)hole- only元件:ITO/ITO/PEDOT:PSS/TCTA:OXD-7/TAPC /MoO3/Al的電流密度對電壓圖、(b)electron-only件:ITO/ZnO/PEIE/TCTA:OXD-7 /OXD-7 /CsF/Al.的電流密度對電壓圖。 24
Figure2-11. 主體mCP藍光TADF材料4CzCF3Ph、5CzCF3Ph的化學結構，與它們元件EL圖型。 25
Figure2-12.藍光TADF材料 DMAC-DPS、CzDMAC-DPS、DCzDMAC-DPS的化學結構，與它們元件EL圖型。 26
Figure2-13. TADF材料CzCF3Ph與5CzCF3Ph的化學結構與元件 EL圖型。 27
Figure2-15.(a)主體CzSi與藍光TADF材料5CzCN化學結構。在結構ITO/PEDOT: PSS /PVK/CzSi+15 wt% or 20 wt% 5CzCN/TSPO1/ TPBi/LiF/Al的發光元件的(b)EL光譜、(c) EQE對元件亮度圖。 29
Figure 2-16. 主體mCP、藍光TADF材料2CzPN與橘磷光PO-01的化學結構圖。 30
Figure 2-17.摻雜0.3 wt%、0.5 wt%、0.8 wt% PO-01之白光元件(c)在不同電壓的EL光譜圖，與(d)元件亮度對EQE與功率效率圖。 31
Figure 2-18.藍光TADF材料DMAC-DPS、綠螢光TTPA與紅螢光DBP的化學結構圖。 32
Figure 2-20.(a)調控間隔層mCP的膜厚，其元件EQE率對電流密度圖。(b)3nm間隔層(mCP)厚度之元件隨著電場改變之EL光譜。 33
Figure 2-22.(a)DMAC-DPS:0.2 wt% TBRDPEPO: DMAC-DPS:0.2wt% TBRb作為發光層之元件的EQE對電流密度圖。(b) DPEPO:DMAC-DPS:0.2 wt% TBRb之元件在不同電壓下的EL光譜。 34
Figure 2-23.藍光TADF材料DMAC-DPS、綠磷光Ir(ppy)2(acac)與紅磷光Ir(PPQ)2(acac)的化學結構圖。 35
Figure 2-24.元件的亮度對EQE和功率效率圖，以即元件在不同電壓下的EL光譜圖。 35
Figure 4-1. Chemical structures of materials investigated and their reative energy diagram. 45
Figure 4-2. The performance characteristics of the devices with various host material.(a)current density and brightness versus applied voltage and (b) luminance versus luminance versus current and power efficiency with various hole injection materials.The device structure is ITO/PEDOT:PSS(35nm) /Host +10 wt% Firpic(40nm)/TmPyPB(50nm)/CsF(1nm)/Al(100nm). 48
Figure 4-3. The current density versus electrical field characteristics of 26DCzPPy doped 20 wt% various hole transport materials in its hole only devices:ITO/PEDOT:PSS(35nm)/ 26DCzPPy:HTM= 8:2(wt%:wt%) + 10 wt% Firpic(45nm) /MoO3(8nm)/Al. 51
Figure 4-4. The performance characteristics of 26DCzPPy doped 20 wt% various hole transport materials as host. (a) current density and brightness versus applied voltage and (b) luminance versus current and power efficiency. The device structure is ITO/PEDOT: PSS(35nm)/26DCzPPy:HTM=8:2(wt%:wt%) +10 wt% Firpic (40nm)/TmPyPB (50nm)/CsF(1nm)/Al(100nm). 52
Figure 4-5. The device performances of Firpic with a various PO-01weight ratio. (a) current density and brightness versus applied voltage, (b) luminance versus current and power efficiency and (c) EL Spectra with CIE coordinate. The device structureisITO/PEDOT:PSS(35nm)/26DCzPPy:TCTA=8:2(wt%:wt%)+10 wt% Firpic:PO-01=100:x (wt%:wt%)(40mn)/TmPyPB(50nm)/CsF (1nm)/Al. 55
Figure 4-6. The device performances of Firpic with various Ir(dpm)PQ2 weight ratio. (a) current density and brightness versus applied voltage, (b) luminance versus current and power efficiency and (c) EL Spectra with CIE coordinate.The device structure is:TCTA=8:2(wt%:wt%)+10 wt %Firpic : Ir(dpm)PQ2=100:x (wt%:wt%)(40mn)/TmPyPB(50nm)/CsF(nm)/CsF(1nm)/Al. 58
Figure 4-7. Electroluminance spectra of Firpic doping (a) 0.6 wt% PO-01and (b)0.4 wt% Ir(dpm)PQ2 devices. The device structure is ITO/PEDOT: PSS(35nm)/ 26DCzPPy: TCTA =8:2(wt%:wt%) 10 wt% Firpic: red dopant =100:x (wt%:wt%)(40nm) /TmPyPB(50nm) /CsF (1nm)/Al. 60
Figure 5-1. Chemical structures of materials investigated and their reative energy diagram.[a] The work function of PEDOT:PSS+PFI is from Ref[68].[b] The HOMO levels of gradient polymer is from Ref[69]. 65
Figure 5-2. UV–vis absorption spectra of (a) 100G-SPF films after thermal annealing at 200℃ for 30 minutes in N2, and (b) PVK+20 wt% PMA films after heating at 140℃ for 30 minutes in N2, before (black line) and after rinsing (red line) with Chlorobenzene. 67
Figure 5-3. The performance characteristics of devices with various hole injection layer.(a)current density and brightness versus applied voltage and (b) luminance versus current and power efficiency. The device structure is ITO/PEDOT:PSS(35nm)/HIL(15nm) /26DCzPPy+10 wt % DMAC- TRZ(45nm) /TmPyPB (50nm)/CsF(1nm)/ Al. 70
Figure 5-4. The current density versus electrical field characteristics of 26DCzPPy doped 20 wt% various hole transport materials in its hole only devices: ITO/PEDOT: PSS (35nm)/26DCzPPy:HTM=8:2(wt%:wt%) +10 wt% DMAC- TRZ(45nm)/MoO3(8nm)/Al. 72
Figure 5-5. The performance characteristics of 26DCzPPy doped 20 wt% various hole transport materials as host. (a) current density and brightness versus applied voltage and (b) luminance versus current and power efficiency. The device structure is ITO/PEDOT: PSS(35nm)/26DCzPPy:HTM=8:2 +10 wt% DMAC- TRZ(45nm) /TmPyPB(50nm)/CsF(1nm)/Al(100nm). 73
Figure 5-6. The device performances of 26DCzPPy with various TCTA weight ratio. (a) current density and brightness versus applied voltage and (b) luminance versus current and power efficiency. 75
Figure 5-7. The device performances with different DMAC-TRZ concentration. (a) current density and brightness versus applied voltage and (b) luminance versus current and power efficiency. 78
Figure 5-8. The device performances of 10 wt% DMAC-TRZ with various thickness. (a) current density and brightness versus applied voltage and (c) luminance versus current and power efficiency. The device performances of 20 wt% DMAC-TRZ with various thickness (b) current density and brightness versus applied voltage and (d) luminance versus current and power efficiency. The device structure is ITO/PEDOT: PSS(35nm) /26DCzPPy: TCTA=8:2 (wt%:wt%)+ x wt% DMAC-TRZ(ynm)/TmPyPB(50nm)/CsF(1nm)/Al (100nm). 80
Figure 5-9. The performances of characteristics of (a) current density and brightness versus applied voltage and (b) luminance versus brightness of the device efficiency with different hole injection layers and DMAC-TRZ concentration. 83
Figure 5-10. The electroluminance spectra of the devices. The device structure is ITO/PEDOT:PSS(35nm)/26DCzPPy:HTM=8:2+10 wt% DMAC-TRZ(45nm) /TmPyPB(50nm)/CsF(1nm)/Al(100nm). 85
Figure 5-11. The electroluminance spectra of the devices. The device structure is ITO/PEDOT:PSS(35nm)/26DCzPPy:TCTA=8:2+x wt% DMAC-TRZ(45nm) /TmPyPB(50nm)/CsF(1nm)/Al(100nm). 86
Figure 5-12. The device performances of DMAC-TRZ with various Ir(dpm)PQ2 weight ratio. (a) current density and brightness versus applied voltage, (b) luminance versus current and power efficiency and (c) EL Spectra with CIE coordinate.The device structure is ITO/PEDOT:PSS(35nm)/26DCzPPy: TCTA=8:2(wt%: wt%) +10 wt% DMAC-TRZ:Ir(dpm)PQ2=100:x(wt%:wt%) (40mn)/TmPyPB.(50nm)/CsF(1nm)/Al. 89
Figure 5-13. The device performances of DMAC-TRZ with various DCJTB weight ratio. (a) current density and brightness versus applied voltage, (b) luminance versus current and power efficiency and (c) EL Spectra with CIE coordinate.The device structure is ITO/PEDOT: PSS(35nm)/ 26DCzPPy: TCTA= 8:2(wt%:wt%) +10 wt% DMAC-TRZ:DCJTB=100:x(wt%:wt%) (40mn)/TmPyPB(50nm)/CsF(1nm)/Al. 92
Figure 5-14. Electroluminance spectra of DMAC-TRZ doping (a) 0.3 wt%Ir(dpm)PQ2 and (b)0.2 wt% DCJTB devices. The device structure is ITO/PEDOT: PSS(35nm)/ 26DCzPPy: TCTA=8:2(wt%:wt%)10 wt% DMAC-TRZ: red dopant=100:x (wt%:wt%)(40nm) /TmPyPB(50nm)/CsF(1nm)/Al.. 94











表目錄
Table 1-1. Device performance for ITO under various treatments. 14
Table 4-1. The performances of devices with various host material.[a] 47
Table 4-2. The device performances of 26DCzPPy with 20 wt% various hole transport materials as host .[a] 50
Table4-3. Device performances of ITO/PEDOT: PSS(35nm)/ 26DCzPPy: TCTA=8:2(wt%: wt%) +10 wt% Firpic:PO-01=100:x(wt%:wt%)(40mn)/ TmPyPB(50nm)/CsF(1nm)/Al. 54
Table4-4. Device performances of ITO/PEDOT: PSS(35nm)/ 26DCzPPy: TCTA=8:2( wt%: wt%)+10 wt% Firpic:Ir(dpm)PQ2=100:x(wt%:wt%)(40mn)
/TmPyPB(50nm) /CsF(1nm)/Al 57
.Table 5-1. The performances of devices with various hole injection layer. [a] 69
Table 5-2. The device performances of 26DCzPPy with 20 wt% various hole transport materials as host .[a] 72
Table 5-3. The device performances of 26DCzPPy with various TCTA weight ratio as host .[a] 74
Table 5-4. The device performances with different DMAC-TRZ concentration (wt%). [a] 77
Table 5-5. The device performances of emission layer with various thickness and different DMAC-TRZ concentration.[a] 79
Table 5-6. The device performances of PEDOT: PSS with a perfluorinated ionomer (PFI) as a hole-injection layer.[a] 82
Table 5-7. Device performances of ITO/PEDOT: PSS(35nm)/ 26DCzPPy: TCTA=8:2(wt%: wt%) +10 wt% DMAC-TRZ:Ir(dpm)PQ2=100:x(wt%:wt%)
(40mn)/TmPyPB(50nm)/CsF(1nm)/Al. 88
Table 5-8. Device performances of ITO/PEDOT: PSS(35nm)/ 26DCzPPy: TCTA=8:2 (wt%: wt%) +10 wt% DMAC-TRZ: DCJTB=100: x (wt%: wt%) (40nm)/TmPyPB(50nm)/CsF(1nm)/Al. 91

[1] Tao, Y.; Yang, C.; Qin, J., Organic host materials for phosphorescent organic light-emitting diodes. Chem Soc Rev 2011, 40 (5), 2943-70.
[2] Rhoderick, E. H.; Williams, R. H., Metal-semiconductor contacts. Clarendon Press Oxford: 1988; Vol. 129.
[3] Burroughes, J.; Bradley, D.; Brown, A.; Marks, R.; Mackay, K.; Friend, R.; Burns, P.; Holmes, A., Light-emitting diodes based on conjugated polymers. nature 1990, 347 (6293), 539-541.
[4] Holmes, A.; Bradley, D.; Brown, A.; Burn, P.; Burroughes, J.; Friend, R.; Greenham, N.; Gymer, R.; Halliday, D.; Jackson, R., Photoluminescence and electroluminescence in conjugated polymeric systems. Synthetic Metals 1993, 57 (1), 4031-4040.
[5] Wohlgenannt, M.; Tandon, K.; Mazumdar, S.; Ramasesha, S.; Vardeny, Z. V., Formation cross-sections of singlet and triplet excitons in π-conjugated polymers. Nature 2001, 409 (6819), 494-497.
[6] Malliaras, G.; Scott, J., The roles of injection and mobility in organic light emitting diodes. Journal of Applied Physics 1998, 83 (10), 5399-5403.
[7] Parker, I. D., Carrier tunneling and device characteristics in polymer light‐emitting diodes. Journal of Applied Physics 1994, 75 (3), 1656-1666.
[8] Blom, P.; De Jong, M.; Vleggaar, J., Electron and hole transport in poly (p‐phenylene vinylene) devices. Applied Physics Letters 1996, 68 (23), 3308-3310.
[9] Brown, A.; Greenham, N.; Burroughes, J.; Bradley, D.; Friend, R.; Burn, P.; Kraft, A.; Holmes, A., Electroluminescence from multilayer conjugated polymer devices: spatial control of exciton formation and emission. Chemical physics letters 1992, 200 (1), 46-54.
[10] Brown, A.; Bradley, D.; Burroughes, J.; Friend, R.; Greenham, N.; Burn, P.; Holmes, A.; Kraft, A., Poly (p‐phenylenevinylene) light‐emitting diodes: Enhanced electroluminescent efficiency through charge carrier confinement. Applied physics letters 1992, 61 (23), 2793-2795.
[11] Greenham, N.; Moratti, S.; Bradley, D.; Friend, R.; Holmes, A., Efficient light-emitting diodes based on polymers with high electron affinities. 1993.
[12] Pei, Q.; Yang, Y., Bright blue electroluminescence from an oxadiazole‐containing copolymer. Advanced Materials 1995, 7 (6), 559-561.
[13] Pei, Q.; Yang, Y., 1, 3, 4-Oxadiazole-containing polymers as electron-injection and blue electroluminescent materials in polymer light-emitting diodes. Chemistry of materials 1995, 7 (8), 1568-1575.
[14] Osada, T.; Kugler, T.; Bröms, P.; Salaneck, W., Polymer-based light-emitting devices: investigations on the role of the indium—tin oxide (ITO) electrode. Synthetic metals 1998, 96 (1), 77-80.
[15] Wu, C.; Wu, C.; Sturm, J.; Kahn, A., Surface modification of indium tin oxide by plasma treatment: An effective method to improve the efficiency, brightness, and reliability of organic light emitting devices. Applied Physics Letters 1997, 70 (11), 1348-1350.
[16] Yang, Y.; Heeger, A., Polyaniline as a transparent electrode for polymer light‐emitting diodes: Lower operating voltage and higher efficiency. Applied Physics Letters 1994, 64 (10), 1245-1247.
[17] Chen, S.-A.; Hwang, G.-W., Synthesis of water-soluble self-acid-doped polyaniline. Journal of the American Chemical Society 1994, 116 (17), 7939-7940.
[18] Chen, S.-A.; Hwang, G.-W., Water-soluble self-acid-doped conducting polyaniline: structure and properties. Journal of the American Chemical Society 1995, 117 (40), 10055-10062.
[19] Cao, Y.; Yu, G.; Zhang, C.; Menon, R.; Heeger, A., Polymer light-emitting diodes with polyethylene dioxythiophene–polystyrene sulfonate as the transparent anode. Synthetic Metals 1997, 87 (2), 171-174.
[20] 羅元宏, 水溶性自身酸摻雜聚苯胺作為電洞傳遞層之高分子發光二極體的特性及其破壞機構的探討. 國立清華大學化工系碩士論文 民國88年.
[21] 李中揚, ITO電極表面處理對高分子發光二極體效能及壽命的影響. 國立清華大學化工系碩士論文 民國89年.
[22] Pinner, D.; Friend, R.; Tessler, N., Transient electroluminescence of polymer light emitting diodes using electrical pulses. Journal of applied physics 1999, 86 (9), 5116-5130.
[23] Campbell, A.; Bradley, D.; Lidzey, D., Space-charge limited conduction with traps in poly (phenylene vinylene) light emitting diodes. Journal of Applied Physics 1997, 82 (12), 6326-6342.
[24] Meyer, H.; Haarer, D.; Naarmann, H.; Hörhold, H., Trap distribution for charge carriers in poly (paraphenylene vinylene)(PPV) and its substituted derivative DPOP-PPV. Physical Review B 1995, 52 (4), 2587.
[25] Lebedev, E.; Dittrich, T.; Petrova-Koch, V.; Karg, S.; Brütting, W., Charge carrier mobility in poly (p-phenylenevinylene) studied by the time-of-flight technique. Applied physics letters 1997, 71 (18), 2686-2688.
[26] Lee, H. M.; Oh, D. K.; Lee, C. H.; Lee, C. E.; Lee, D. W.; Jin, J. I., Time-of-flight measurements of charge-carrier mobilities in a poly (p-phenylenevinylene) derivative carrying an electron-transporting moiety. Synthetic metals 2001, 119 (1-3), 473-474.
[27] Crone, B.; Campbell, I.; Davids, P.; Smith, D., Charge injection and transport in single-layer organic light-emitting diodes. Applied physics letters 1998, 73 (21), 3162-3164.
[28] Bozano, L.; Carter, S.; Scott, J.; Malliaras, G.; Brock, P., Temperature-and field-dependent electron and hole mobilities in polymer light-emitting diodes. Applied Physics Letters 1999, 74 (8), 1132.
[29] Fu, Q.; Chen, J.; Shi, C.; Ma, D., Solution-processed small molecules as mixed host for highly efficient blue and white phosphorescent organic light-emitting diodes. ACS Appl Mater Interfaces 2012, 4 (12), 6579-86.
[30] Fu, Q.; Chen, J.; Zhang, H.; Shi, C.; Ma, D., Solution-processed single-emitting-layer white organic light-emitting diodes based on small molecules with efficiency/CRI/color-stability trade-off. Opt Express 2013, 21 (9), 11078-85.
[31] Aizawa, N.; Pu, Y. J.; Chiba, T.; Kawata, S.; Sasabe, H.; Kido, J., Instant low-temperature cross-linking of poly(N-vinylcarbazole) for solution-processed multilayer blue phosphorescent organic light-emitting devices. Adv Mater 2014, 26 (45), 7543-6.
[32] Fan, C.; Lei, Y.; Liu, Z.; Wang, R.; Lei, Y.; Li, G.; Xiong, Z.; Yang, X., High-Efficiency Phosphorescent Hybrid Organic-Inorganic Light-Emitting Diodes Using a Solution-Processed Small-Molecule Emissive Layer. ACS Appl Mater Interfaces 2015, 7 (37), 20769-78.
[33] Lin, T. A.; Chatterjee, T.; Tsai, W. L.; Lee, W. K.; Wu, M. J.; Jiao, M.; Pan, K. C.; Yi, C. L.; Chung, C. L.; Wong, K. T.; Wu, C. C., Sky-Blue Organic Light Emitting Diode with 37% External Quantum Efficiency Using Thermally Activated Delayed Fluorescence from Spiroacridine-Triazine Hybrid. Adv Mater 2016, 28 (32), 6976-83.
[34] Shin, H.; Lee, J. H.; Moon, C. K.; Huh, J. S.; Sim, B.; Kim, J. J., Sky-Blue Phosphorescent OLEDs with 34.1% External Quantum Efficiency Using a Low Refractive Index Electron Transporting Layer. Adv Mater 2016, 28 (24), 4920-5.
[35] Mei, L.; Hu, J.; Cao, X.; Wang, F.; Zheng, C.; Tao, Y.; Zhang, X.; Huang, W., The inductive-effect of electron withdrawing trifluoromethyl for thermally activated delayed fluorescence: tunable emission from tetra- to penta-carbazole in solution processed blue OLEDs. Chem. Commun. 2015, 51 (65), 13024-13027.
[36] Luo, J.; Gong, S.; Gu, Y.; Chen, T.; Li, Y.; Zhong, C.; Xie, G.; Yang, C., Multi-carbazole encapsulation as a simple strategy for the construction of solution-processed, non-doped thermally activated delayed fluorescence emitters. J. Mater. Chem. C 2016, 4 (13), 2442-2446.
[37] Liu, Y.; Xie, G.; Wu, K.; Luo, Z.; Zhou, T.; Zeng, X.; Yu, J.; Gong, S.; Yang, C., Boosting reverse intersystem crossing by increasing donors in triarylboron/phenoxazine hybrids: TADF emitters for high-performance solution-processed OLEDs. J. Mater. Chem. C 2016, 4 (20), 4402-4407.
[38] Wada, Y.; Shizu, K.; Kubo, S.; Fukushima, T.; Miwa, T.; Tanaka, H.; Adachi, C.; Kaji, H., Highly efficient solution-processed host-free organic light-emitting diodes showing an external quantum efficiency of nearly 18% with a thermally activated delayed fluorescence emitter. Applied Physics Express 2016, 9 (3), 032102.
[39] Cho, Y. J.; Jeon, S. K.; Lee, J. Y., Molecular Engineering of High Efficiency and Long Lifetime Blue Thermally Activated Delayed Fluorescent Emitters for Vacuum and Solution Processed Organic Light-Emitting Diodes. Advanced Optical Materials 2016, 4 (5), 688-693.
[40] Zhang, D.; Duan, L.; Zhang, Y.; Cai, M.; Zhang, D.; Qiu, Y., Highly efficient hybrid warm white organic light-emitting diodes using a blue thermally activated delayed fluorescence emitter: exploiting the external heavy-atom effect. Light: Science & Applications 2015, 4 (1), e232.
[41] Zhang, D.; Cai, M.; Zhang, Y.; Zhang, D.; Duan, L., Highly Efficient Simplified Single-Emitting-Layer Hybrid WOLEDs with Low Roll-off and Good Color Stability through Enhanced Forster Energy Transfer. ACS Appl Mater Interfaces 2015, 7 (51), 28693-700.
[42] Higuchi, T.; Nakanotani, H.; Adachi, C., High-efficiency white organic light-emitting diodes based on a blue thermally activated delayed fluorescent emitter combined with green and red fluorescent emitters. Adv Mater 2015, 27 (12), 2019-23.
[43] Wu, Z.; Yu, L.; Zhou, X.; Guo, Q.; Luo, J.; Qiao, X.; Yang, D.; Chen, J.; Yang, C.; Ma, D., Management of Singlet and Triplet Excitons: A Universal Approach to High-Efficiency All Fluorescent WOLEDs with Reduced Efficiency Roll-Off Using a Conventional Fluorescent Emitter. Advanced Optical Materials 2016, 4 (7), 1067-1074.
[44] Wu, Z.; Luo, J.; Sun, N.; Zhu, L.; Sun, H.; Yu, L.; Yang, D.; Qiao, X.; Chen, J.; Yang, C.; Ma, D., High-Performance Hybrid White Organic Light-Emitting Diodes with Superior Efficiency/Color Rendering Index/Color Stability and Low Efficiency Roll-Off Based on a Blue Thermally Activated Delayed Fluorescent Emitter. Advanced Functional Materials 2016, 26 (19), 3306-3313.
[45] Klubek, K. P.; Dong, S.-C.; Liao, L.-S.; Tang, C. W.; Rothberg, L. J., Investigating blue phosphorescent iridium cyclometalated dopant with phenyl-imidazole ligands. Organic Electronics 2014, 15 (11), 3127-3136.
[46] Zhang, Y.; Lee, J.; Forrest, S. R., Tenfold increase in the lifetime of blue phosphorescent organic light-emitting diodes. Nat Commun 2014, 5, 5008.
[47] Shin, H.; Lee, S.; Kim, K. H.; Moon, C. K.; Yoo, S. J.; Lee, J. H.; Kim, J. J., Blue phosphorescent organic light-emitting diodes using an exciplex forming co-host with the external quantum efficiency of theoretical limit. Adv Mater 2014, 26 (27), 4730-4.
[48] Lee, J.-H.; Cheng, S.-H.; Yoo, S.-J.; Shin, H.; Chang, J.-H.; Wu, C.-I.; Wong, K.-T.; Kim, J.-J., An Exciplex Forming Host for Highly Efficient Blue Organic Light Emitting Diodes with Low Driving Voltage. Advanced Functional Materials 2015, 25 (3), 361-366.
[49] Udagawa, K.; Sasabe, H.; Cai, C.; Kido, J., Low-driving-voltage blue phosphorescent organic light-emitting devices with external quantum efficiency of 30%. Adv Mater 2014, 26 (29), 5062-6.
[50] Udagawa, K.; Sasabe, H.; Igarashi, F.; Kido, J., Simultaneous Realization of High EQE of 30%, Low Drive Voltage, and Low Efficiency Roll-Off at High Brightness in Blue Phosphorescent OLEDs. Advanced Optical Materials 2016, 4 (1), 86-90.
[51] Liu, J.; Pei, Q., Poly(m-phenylene): Conjugated Polymer Host with High Triplet Energy for Efficient Blue Electrophosphorescence. Macromolecules 2010, 43 (23), 9608-9612.
[52] Shao, S.; Ding, J.; Ye, T.; Xie, Z.; Wang, L.; Jing, X.; Wang, F., A novel, bipolar polymeric host for highly efficient blue electrophosphorescence: a non-conjugated poly(aryl ether) containing triphenylphosphine oxide units in the electron-transporting main chain and carbazole units in hole-transporting side chains. Adv Mater 2011, 23 (31), 3570-4.
[53] Hu, D.; Cheng, G.; Lu, P.; Liu, H.; Shen, F.; Li, F.; Lv, Y.; Dong, W.; Ma, Y., Peripheral cyanohexyl substituent in wide bandgap polymer: increase the electron injection property for blue phosphorescence light emitting device. Macromol Rapid Commun 2011, 32 (18), 1467-71.
[54] Ding, J.; Zhang, B.; Lu, J.; Xie, Z.; Wang, L.; Jing, X.; Wang, F., Solution-processable carbazole-based conjugated dendritic hosts for power-efficient blue-electrophosphorescent devices. Adv Mater 2009, 21 (48), 4983-6.
[55] Tao, Y.; Guo, X.; Hao, L.; Chen, R.; Li, H.; Chen, Y.; Zhang, X.; Lai, W.; Huang, W., A Solution-Processed Resonance Host for Highly Efficient Electrophosphorescent Devices with Extremely Low Efficiency Roll-off. Adv Mater 2015, 27 (43), 6939-44.
[56] Chou, H. H.; Cheng, C. H., A highly efficient universal bipolar host for blue, green, and red phosphorescent OLEDs. Adv Mater 2010, 22 (22), 2468-71.
[57] Su, S.-J.; Cai, C.; Kido, J., RGB Phosphorescent Organic Light-Emitting Diodes by Using Host Materials with Heterocyclic Cores: Effect of Nitrogen Atom Orientations. Chemistry of Materials 2011, 23 (2), 274-284.
[58] Noine, K.; Kimura, S.; Pu, Y.-J.; Nakayama, K.-i.; Yokoyama, M.; Kido, J., Red Phosphorescent Iridium Complexes having a Bulky Ancillary Ligand for Solution-processed Organic Light Emitting Diodes. Journal of Photopolymer Science and Technology 2008, Vol. 21 (2008) 323-325.
[59] Zhang, J.; Ding, D.; Wei, Y.; Xu, H., Extremely condensing triplet states of DPEPO-type hosts through constitutional isomerization for high-efficiency deep-blue thermally activated delayed fluorescence diodes. Chem. Sci. 2016, 7 (4), 2870-2882.
[60] Zhang, J.; Ding, D.; Wei, Y.; Han, F.; Xu, H.; Huang, W., Multiphosphine-Oxide Hosts for Ultralow-Voltage-Driven True-Blue Thermally Activated Delayed Fluorescence Diodes with External Quantum Efficiency beyond 20. Adv Mater 2016, 28 (3), 479-85.
[61] Zhang, Q.; Li, B.; Huang, S.; Nomura, H.; Tanaka, H.; Adachi, C., Efficient blue organic light-emitting diodes employing thermally activated delayed fluorescence. Nature Photonics 2014, 8 (4), 326-332.
[62] Cui, L. S.; Deng, Y. L.; Tsang, D. P.; Jiang, Z. Q.; Zhang, Q.; Liao, L. S.; Adachi, C., Controlling Synergistic Oxidation Processes for Efficient and Stable Blue Thermally Activated Delayed Fluorescence Devices. Adv Mater 2016, 28 (35), 7620-5.
[63] Cho, Y. J.; Yook, K. S.; Lee, J. Y., High efficiency in a solution-processed thermally activated delayed-fluorescence device using a delayed-fluorescence emitting material with improved solubility. Adv Mater 2014, 26 (38), 6642-6.
[64] Hirata, S.; Sakai, Y.; Masui, K.; Tanaka, H.; Lee, S. Y.; Nomura, H.; Nakamura, N.; Yasumatsu, M.; Nakanotani, H.; Zhang, Q.; Shizu, K.; Miyazaki, H.; Adachi, C., Highly efficient blue electroluminescence based on thermally activated delayed fluorescence. Nat Mater 2015, 14 (3), 330-6.
[65] Park, I. S.; Lee, S. Y.; Adachi, C.; Yasuda, T., Full-Color Delayed Fluorescence Materials Based on Wedge-Shaped Phthalonitriles and Dicyanopyrazines: Systematic Design, Tunable Photophysical Properties, and OLED Performance. Advanced Functional Materials 2016, 26 (11), 1813-1821.
[66] Tsai, W. L.; Huang, M. H.; Lee, W. K.; Hsu, Y. J.; Pan, K. C.; Huang, Y. H.; Ting, H. C.; Sarma, M.; Ho, Y. Y.; Hu, H. C.; Chen, C. C.; Lee, M. T.; Wong, K. T.; Wu, C. C., A versatile thermally activated delayed fluorescence emitter for both highly efficient doped and non-doped organic light emitting devices. Chem Commun (Camb) 2015, 51 (71), 13662-5.
[67] Yao, Y. S.; Zhou, Q. X.; Wang, X. S.; Wang, Y.; Zhang, B. W., A DCM-Type Red-Fluorescent Dopant for High-Performance Organic Electroluminescent Devices. Advanced Functional Materials 2007, 17 (1), 93-100.
[68] Lee, T. W.; Chung, Y.; Kwon, O.; Park, J. J., Self-Organized Gradient Hole Injection to Improve the Performance of Polymer Electroluminescent Devices. Advanced Functional Materials 2007, 17 (3), 390-396.
[69] Huang, C.-W.; Tsai, C.-L.; Liu, C.-Y.; Jen, T.-H.; Yang, N.-J.; Chen, S.-A., Design of Deep Blue Electroluminescent Spiro-Polyfluorenes with High Efficiency by Facilitating the Injection of Charge Carriers through Incorporation of Multiple Charge Transport Moieties. Macromolecules 2012, 45 (3), 1281-1287.