Highly efficient and air-stable inverted organic light-emitting diode composed of inert materials

Fukagawa, Hirohiko; Morii, Katsuyuki; Hasegawa, Munehiro; Arimoto, Yoichi; Kamada, Taisuke; Shimizu, Takahisa; Yamamoto, Toshihiro

doi:10.7567/apex.7.082104

Cited by 72 publications

(69 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As the OLED emission layer, we employed an airstable inverted OLED (iOLED) device. This iOLED does not use an air-reactive electrode and injection layer, giving it a longer lifetime than a conventional OLED without a hard passivation layer [9,10]. The iOLED also has good compatibility with n-type pixel-driving circuits.…”

Section: Itzo-tft-driven Flexible Oled Displaymentioning

confidence: 99%

47-2:Invited Paper: Oxide/Organic Semiconductor Electronics on Plastic Substrates for Flexible AMOLED Displays

Fujisaki¹,

Nakata²,

Nakajima³

et al. 2016

SID Symposium Digest of Technical Papers

Self Cite

View full text Add to dashboard Cite

Emerging flexible OLED display technologies are expected to bring a new viewing experience to a wide range of display applications from mobile terminals and signage to large-area sheet-type displays. For large-area and high-resolution flexible OLED displays, however, the development of high-performance and reliable TFT backplanes on plastic substrates is still an essential and challenging research subject. Here, we discuss our recent work on the development of oxide TFTs and their application to flexible OLED displays. In addition, solution-based organic materials and devices, which are advantageous for the simple fabrication of large-area backplanes, are discussed.

show abstract

Section: Itzo-tft-driven Flexible Oled Displaymentioning

confidence: 99%

47-2:Invited Paper: Oxide/Organic Semiconductor Electronics on Plastic Substrates for Flexible AMOLED Displays

Fujisaki¹,

Nakata²,

Nakajima³

et al. 2016

SID Symposium Digest of Technical Papers

Self Cite

View full text Add to dashboard Cite

show abstract

“…32 In this case, the thickness of the used buffer layer has to be exactly controlled. 1. For comparison, we also fabricated inverted reference device (ref.…”

Section: Thickness-dependent Characteristics Of Zns Lmmentioning

confidence: 99%

“…1,2 So far, small OLED panels are already being utilized for cellular phones. 1,2 So far, small OLED panels are already being utilized for cellular phones.…”

Section: Introductionmentioning

confidence: 99%

“…The development of an inverted OLED (IOLED) is one of the efforts to match OLEDs to the existing n-type amorphous silicon thin lm transistor (TFT) technology. 1,14 High-work function metal oxides such as tungsten oxide (WO 3 ), 15,16 vanadium pentoxide (V 2 O 5 ) 17,18 or molybdenum oxide (MoO 3 ) 19,20 have been widely used for hole-injection materials. 8 Moreover, OLEDs with inverted architectures provide longer device lifetime because water-and oxygensensitive electron injection materials can be kept beneath the organic and metal layers.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Extremely high external quantum efficiency of inverted organic light-emitting diodes with low operation voltage and reduced efficiency roll-off by using sulfide-based double electron injection layers

Guo

Zhang

et al. 2016

RSC Adv.

View full text Add to dashboard Cite

Inverted organic light-emitting diodes (IOLEDs) have great potential application in flat-panel displays. High energy consumption, efficiency roll-off, and poor electron injection are key issues limiting the use of IOLEDs. Here, we present IOLEDs with extremely low driving voltage, high efficiency and efficiency rollup by employing double electron injection layers (D-EILs) composed of metal sulfide and cesium carbonate (Cs 2 CO 3 )-doped 4,7-diphenyl-1,10-phenanthroline (Bphen). We demonstrate that the use of D-EILs with metal sulfides can significantly improve the performance of IOLEDs. For a blue florescent device based on (2 nm-zinc sulfide)/Bphen: Cs 2 CO 3 , we achieve a power efficiency of 10.9 lm W À1 at a luminance of 1000 cd m À2 , giving a turn-on voltage of 2.8 V. Notably, the external quantum efficiency increases from 6.9 to 7.5% and the current efficiency increases from 14.3 to 15.4 cd A À1 with the rise in luminance from 1000 to 10 000 cd m À2 . Also, the copper sulfide-based device exhibits very-low operating voltages of 4.0 V and 5.3 V at the luminance of 1000 and 10 000 cd m À2 , respectively. For a green phosphorescent device, approximately 1.2-fold improvement in external quantum efficiency was obtained compared to the conventional structure. We attributed the improved performance to dipoledipole interactions at the sulfide-organic interface. View Article Onlinea Measured at luminance of 1 cd m À2 . b Measured at luminance of 1000 cd m À2 . c Measured at luminance of 10 000 cd m À2 . This journal is

show abstract

“…Nevertheless, their intrinsic low environmental stability requires rigorous encapsulation to enhance their lifetime, which directly increases the final cost of the devices and thus limits the competiveness of OLEDs. Inverted-structured OLEDs have recently been reported as potential substitutes for conventional OLEDs [8][9][10][11]. In these devices, air-stable metals with high work functions were used as the anode, indium tin oxide (ITO) was used as the cathode, and air-stable metal-oxide layers were used as the electron-injection layers (EILs) and hole-injection layers (HILs).…”

mentioning

confidence: 99%

Highly efficient inverted organic light-emitting diodes based on thermally activated delayed fluorescence

et al. 2016

View full text Add to dashboard Cite

Organic light-emitting diodes (OLEDs) have attracted increasing attention because of their advantages of low power consumption, light weight, fast response time, large viewing angle, high brightness, and mechanical flexibility [1][2][3][4]. Many efforts have been made to prepare high-performance OLEDs with excellent stability in the past two decades, and some products based on OLEDs have been introduced to the market [5][6][7]. Nevertheless, their intrinsic low environmental stability requires rigorous encapsulation to enhance their lifetime, which directly increases the final cost of the devices and thus limits the competiveness of OLEDs. Inverted-structured OLEDs have recently been reported as potential substitutes for conventional OLEDs [8][9][10][11]. In these devices, air-stable metals with high work functions were used as the anode, indium tin oxide (ITO) was used as the cathode, and air-stable metal-oxide layers were used as the electron-injection layers (EILs) and hole-injection layers (HILs). These metal oxides result in exceptional stability, mechanical and electrical robustness, low cost, transparency in the visible region, and solution-processable fabrication. Thus, the high stability of inverted OLEDs can be expected to fulfill the requirements of real applications. In addition, the inverted OLEDs have a bottom ITO cathode and can be directly connected to the drain electrode of a-Si thin film transistors, facilitating the fabrication of active matrix OLEDs for large-area displays. Although metal oxides can encapsulate the organic emitting layers from oxygen and moisture, the stability and performance of inverted OLEDs are unsatisfactory because of the limited stability of phosphorescent emitters and unbalanced hole and electron injection.Thermally activated delayed fluorescent (TADF) emitters yield stable fluorescence with very high singlet yields, as these materials exhibit sufficiently small energy gaps between singlets and triplets to enable the up-conversion of triplet excitons to singlet excitons and then realize 100% internal quantum efficiency (IQE) of the singlet excitons formed by electric excitation. Versatile TADF emitters have been reported, including spiro-acridine, triazine, diphenyl sulfone derivatives, and thioxanthone (TX) derivatives [12][13][14][15]. OLEDs based on TADF emitters afford high

show abstract

Highly efficient and air-stable inverted organic light-emitting diode composed of inert materials

Cited by 72 publications

References 20 publications

47-2:Invited Paper: Oxide/Organic Semiconductor Electronics on Plastic Substrates for Flexible AMOLED Displays

47-2:Invited Paper: Oxide/Organic Semiconductor Electronics on Plastic Substrates for Flexible AMOLED Displays

Extremely high external quantum efficiency of inverted organic light-emitting diodes with low operation voltage and reduced efficiency roll-off by using sulfide-based double electron injection layers

Highly efficient inverted organic light-emitting diodes based on thermally activated delayed fluorescence

Contact Info

Product

Resources

About