scholarly journals Comparative Study of Printed Multilayer OLED Fabrication through Slot Die Coating, Gravure and Inkjet Printing, and Their Combination

2019 ◽  
Vol 3 (1) ◽  
pp. 32 ◽  
Author(s):  
Lisa Merklein ◽  
Dominik Daume ◽  
Felix Braig ◽  
Stefan Schlisske ◽  
Tobias Rödlmeier ◽  
...  
Keyword(s):  
Inkjet Printing ◽  
Hole Transport ◽  
Transport Layer ◽  
Hole Injection ◽  
Process Window ◽  
Gravure Printing ◽  
Solution Processed ◽  
Slot Die Coating ◽  
Slot Die ◽  
Application Techniques

In this study, multilayer organic light-emitting diodes (OLEDs) consisting of three solution-processed layers are fabricated using slot die coating, gravure printing, and inkjet printing, techniques that are commonly used in the industry. Different technique combinations are investigated to successively deposit a hole injection layer (poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS)), a cross-linkable hole transport layer (N,N′-bis(4-(6-((3-ethyloxetan-3-yl)methoxy)-hexyloxy)phenyl)-N,N′-bis(4-methoxyphenyl)biphenyl-4,4′-diamin (QUPD)), and a green emissive layer (TSG-M) on top of each other. In order to compare the application techniques, the ink formulations have to be adapted to the respective process requirements. First, the influence of the application technique on the layer homogeneity of the different materials is investigated. Large area thickness measurements of the layers based on imaging color reflectometry (ICR) are used to compare the application techniques regarding the layer homogeneity and reproducible film thickness. The total stack thickness of all solution-processed layers of 32 OLEDs could be reproduced homogeneously in a process window of 30 nm for the technique combination of slot die coating and inkjet printing. The best efficiency of 13.3 cd A−1 is reached for a process combination of slot die coating and gravure printing. In order to enable a statistically significant evaluation, in total, 96 OLEDs were analyzed and the corresponding 288 layers were measured successively to determine the influence of layer homogeneity on device performance.

scholarly journals Interlayer Engineering of Flexible and Large Area Red Organic Light Emitting Diodes Based on a N-Annulated Perylene Diimide Dimer

2019 ◽  
Author(s):  
Mohammad Rahmati ◽  
Majid Pahlevani ◽  
Gregory Welch
Keyword(s):  
Red Light ◽  
Ambient Air ◽  
Hole Transport ◽  
Transport Layer ◽  
Hole Injection ◽  
Hole Transport Layer ◽  
Large Area ◽  
Average Roughness ◽  
Light Emitting ◽  
Slot Die

<p>Flexible red OLEDs based on a quadruple layer stack in-between electrodes with 160 mm<sup>2</sup> active area were fabricated in ambient air on PET via slot-die coating. For the OLED structure PET/ITO/PEDOT:PSS/PVK/PFO:tPDI<sub>2</sub>N-EH/ZnO/Ag the ink formulations and coating parameters for each layer were systematically evaluated and optimized. The air-stable red-light emitting material tPDI<sub>2</sub>N-EH was successfully utilized as blended homogeneous film with PFO for the emitting layer. The use of an organic hole-transport layer (PVK) and inorganic electron injection layer (ZnO) significantly improved the brightness of the reference device from 4 cd/m<sup>2</sup> to 303 cd/m<sup>2</sup>. Surface analysis using AFM measurements showed that PVK interlayer reduced the surface roughness of the hole injection layer (PEDT:PSS) from 0.45 nm to 0.17 nm, which improved the ability to form uniform emitting layers on top. In addition, the ZnO interlayer improved the average roughness of the device from 1.26 nm to 0.85 nm and reduced the turn-on voltage of the device from 5.0 V to 2.8 V.</p>

scholarly journals Interlayer Engineering of Flexible and Large Area Red Organic Light Emitting Diodes Based on a N-Annulated Perylene Diimide Dimer

2019 ◽  
Author(s):  
Mohammad Rahmati ◽  
Majid Pahlevani ◽  
Gregory Welch
Keyword(s):  
Red Light ◽  
Ambient Air ◽  
Hole Transport ◽  
Transport Layer ◽  
Hole Injection ◽  
Hole Transport Layer ◽  
Large Area ◽  
Average Roughness ◽  
Light Emitting ◽  
Slot Die

<p>Flexible red OLEDs based on a quadruple layer stack in-between electrodes with 160 mm<sup>2</sup> active area were fabricated in ambient air on PET via slot-die coating. For the OLED structure PET/ITO/PEDOT:PSS/PVK/PFO:tPDI<sub>2</sub>N-EH/ZnO/Ag the ink formulations and coating parameters for each layer were systematically evaluated and optimized. The air-stable red-light emitting material tPDI<sub>2</sub>N-EH was successfully utilized as blended homogeneous film with PFO for the emitting layer. The use of an organic hole-transport layer (PVK) and inorganic electron injection layer (ZnO) significantly improved the brightness of the reference device from 4 cd/m<sup>2</sup> to 303 cd/m<sup>2</sup>. Surface analysis using AFM measurements showed that PVK interlayer reduced the surface roughness of the hole injection layer (PEDT:PSS) from 0.45 nm to 0.17 nm, which improved the ability to form uniform emitting layers on top. In addition, the ZnO interlayer improved the average roughness of the device from 1.26 nm to 0.85 nm and reduced the turn-on voltage of the device from 5.0 V to 2.8 V.</p>

scholarly journals Towards industrialization of perovskite solar cells using slot die coating

2020 ◽  
Vol 8 (18) ◽  
pp. 6124-6135 ◽  
Author(s):  
Anand Verma ◽  
David Martineau ◽  
Erwin Hack ◽  
Mohammed Makha ◽  
Erik Turner ◽  
...  
Keyword(s):  
Solar Cells ◽  
Screen Printing ◽  
Perovskite Solar Cells ◽  
Hole Transport ◽  
Transport Layer ◽  
Hole Transport Layer ◽  
Slot Die Coating ◽  
Slot Die ◽  
Carbon Based

Carbon-based hole transport layer-free mesoscopic perovskite solar cells can be manufactured at industrially relevant speeds on large areas using slot die coating. The cells show efficiencies comparable to those manufactured by screen printing.

Inkjet printed organic light-emitting diodes employing organometal-halide perovskite as hole transport layer

2021 ◽  
Author(s):  
Lei Liu ◽  
Dongyu Zhang ◽  
Tao Chu ◽  
Yihua Jian ◽  
fan yu ◽  
...  
Keyword(s):  
Inkjet Printing ◽  
Power Efficiency ◽  
Light Emitting Diodes ◽  
Surface Defects ◽  
Hole Transport ◽  
Transport Layer ◽  
Hole Injection ◽  
Hole Transport Layer ◽  
Light Emitting ◽  
Perovskite Materials

Abstract Due to their narrow spectrum and high photoluminescence quantum yield, organic-inorganic hybrid perovskite materials have become an important emitter for light-emitting diodes (LED). In addition to the perovskite emitters, other perovskite materials such as methyl lead ammonium chloride (MAPbCl3) with high charge mobility can potentially be used as excellent charge transport materials. In this work, phosphorescence LED devices in which MAPbCl3 was employed as hole transport layer (HTL) was designed and fabricated by inkjet printing process. Ethanolamine was added to the PEDOT:PSS hole injection layer (HIL) to control the crystallization process and to suppress the surface defects of MAPbCl3. In addition, polyethylene oxide was doped into MAPbCl3 to improve the printability and the quality of film formation. The "blurred interface" concept was successively applied to enable for the first time the inkjet printing of three layers (HIL, HTL and emitter layers) in the LEDs. The fabricated multilayer LEDs achieved the maximum external quantum efficiency of 8.9 %, maximum current efficiency of 30.8 cd/A, and maximum power efficiency of 10.7 lm/W. A 40*40 mm2 OLED light emitting device was successfully fabricated by inkjet printing technology.

The Study of Hole Injection in OLEDs with Ultra-Thin Sol-Gel TiO2 Layer

2011 ◽  
Vol 189-193 ◽  
pp. 42-46
Author(s):  
You Wang Hu ◽  
Xiao Yan Sun ◽  
Jian Duan
Keyword(s):  
Sol Gel ◽  
Hole Transport ◽  
Organic Light Emitting Diodes ◽  
Transport Layer ◽  
Hole Injection ◽  
Hole Transport Layer ◽  
Carrier Injection ◽  
Light Emitting ◽  
Organic Light ◽  
Pre Treatment

Organic light-emitting diodes (OLEDs) with inserting an ultrathin sol–gel titanium oxide (TiO2) buffer layer between the ITO anode and hole transport layer (HTL) were fabricated. The carrier injection and the device efficiency were affected by surface morphology of TiO2, which was changed by different plasma pre-treatment of ITO. Treated by CF4 plasma, the TiO2 layer is the smoothest, and treated by H2 plasma it is like island. The TiO2 layer like island is favor of carrier injection from the anode, which was attributed to the point discharged.

Solution processed pristine PDPP3T polymer as hole transport layer for efficient perovskite solar cells with slower degradation

2016 ◽  
Vol 145 ◽  
pp. 193-199 ◽  
Author(s):  
Ashish Dubey ◽  
Nirmal Adhikari ◽  
Swaminathan Venkatesan ◽  
Shaopeng Gu ◽  
Devendra Khatiwada ◽  
...  
Keyword(s):  
Solar Cells ◽  
Perovskite Solar Cells ◽  
Hole Transport ◽  
Transport Layer ◽  
Hole Transport Layer ◽  
Solution Processed

scholarly journals Widely applicable phosphomolybdic acid doped poly(9-vinylcarbazole) hole transport layer for perovskite light-emitting devices

RSC Advances ◽  
2019 ◽  
Vol 9 (52) ◽  
pp. 30398-30405
Author(s):  
Yanting Wu ◽  
Zewu Xiao ◽  
Lihong He ◽  
Xiaoli Yang ◽  
Yajun Lian ◽  
...  
Keyword(s):  
Phosphomolybdic Acid ◽  
Hole Transport ◽  
Transport Layer ◽  
Hole Injection ◽  
Hole Transport Layer ◽  
Light Emitting ◽  
Light Emitting Devices ◽  
Wide Range ◽  
Selection Of ◽  
Range Selection

Perovskite light-emitting devices using a PVK:PMA hole transport layer show robust performance, allowing the wide range selection of antisolvents and hole injection layers.

Sign in / Sign up

Export Citation Format

Share Document