Enabling High-Throughput, Low-Cost Manufacturing of OLED Display and Lighting Panels

2009 ◽  
Vol 1212 ◽  
Author(s):  
Michael Long ◽  
Bruce E Koppe ◽  
Neil P Redden ◽  
Michael L Boroson ◽  
Tukaram K Hatwar ◽  
...  

AbstractLarge-scale manufacturing of organic light-emitting diode (OLED) panels for lighting and display has been slowed by several manufacturing factors, prominent among which are low throughput due in part to the fine metal mask technology for patterning the red-, green-, and blue-light-emitting pixels and low materials utilization efficiency of the available vacuum deposition technology. To overcome these impediments to low-cost OLED manufacturing, Kodak developed a blanket white-emitting OLED architecture in combination with a pixilated color filter array to eliminate the need for fine metal masks and developed a vacuum deposition technology capable of high deposition rates and high materials utilization efficiency. These developments, taken together, allow much higher throughput and yield on fifth-generation and larger substrates that promise to enable low-cost manufacturing of OLED displays and lighting panels. This paper focuses on the deposition technology Kodak developed, a flash vaporization process that can deliver very high materials utilization efficiency at high deposition rates for small-molecule OLED materials without increasing material decomposition.

Nanomaterials ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 686 ◽  
Author(s):  
Marta Stucchi ◽  
Daria Boffito ◽  
Eleonora Pargoletti ◽  
Giuseppina Cerrato ◽  
Claudia Bianchi ◽  
...  

TiO2-based photocatalysis under visible light is an attractive way to abate air pollutants. Moreover, developing photocatalytic materials on a large-scale requires safe and low-cost precursors. Both high-performance TiO2 nanopowders and visible-light active noble metals do not match these requirements. Here, we report the design of novel Mn-decorated micrometric TiO2 particles. Pigmentary TiO2 replaced unsafe nano-TiO2 and firmly supported MnOx particles. Mn replaced noble metals such as Au or Ag, opening the way for the development of lower cost catalysts. Varying Mn loading or pH during the impregnation affected the final activity, thus giving important information to optimize the synthesis. Photocatalytic activity screening occurred on the gas-phase degradation of ethanol as a reference molecule, both under ultraviolet (UV) (6 h) and Light Emitting Diode (LED) (24 h) irradiation. Mn-doped TiO2 reached a maximum ethanol degradation of 35% under visible light after 24 h for the sample containing 20% of Mn. Also, we found that an acidic pH increased both ethanol degradation and mineralization to CO2, while an alkaline pH drastically slowed down the reaction. A strict correlation between photocatalytic results and physico-chemical characterizations of the synthesized powders were drawn.


2020 ◽  
pp. 095400832094538
Author(s):  
Deepika C Hasija ◽  
Vaijayanti D Ghase ◽  
Meenakshi M Rananaware ◽  
Vishwanath R Patil

A set of anthracene containing polyfluorenes (PFs) having 9,10-diphenylanthracene with alkyl substituents and aniline containing fluorenes were prepared. Commonly, light-emitting polymers were synthesized using expensive palladium-like catalysts. In the present work, palladium was replaced by copper as a cost-effective PF synthesis catalyst, which is also suitable for large-scale polymer synthesis. Synthesized PFs emit light in the blue region with a bandgap of 2.87–2.90 eV. Thermally stable PFs had a decomposition temperature of more than 305°C and a glass transition temperature of 125–138°C. PFs were soluble in organic solvents and had a molecular weight of around 21,700–25,500. The electrochemical study of these PFs showed low level of highest occupied molecular orbital (HOMO) energy of −5.16 to −5.26 eV, which was significantly higher than that of PF (5.7 eV). These findings suggested that the resulting PFs could be used as a component of the light-emitting diode.


Photonics ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 209
Author(s):  
Gopi Chandra Adhikari ◽  
Saroj Thapa ◽  
Yang Yue ◽  
Hongyang Zhu ◽  
Peifen Zhu

All-inorganic lead halide perovskite (CsPbX3) nanocrystals (NCs) have emerged as a highly promising new generation of light emitters due to their extraordinary photophysical properties. However, the performance of these semiconducting NCs is undermined due to the inherent toxicity of lead and long-term environmental stability. Here, we report the addition of B-site cation and X-site anion (pseudo-halide) concurrently using Ba(SCN)2 (≤50%) in CsPbX3 NCs to reduce the lead and improve the photophysical properties and stability. The as-grown particles demonstrated an analogous structure with an almost identical lattice constant and a fluctuation of particle size without altering the morphology of particles. Photoluminescence quantum yield is enhanced up to near unity (~98%) by taking advantage of concomitant doping at the B- and X-site of the structure. Benefitted from the defect reductions and stronger bonding interaction between Pb2+ and SCN− ions, Ba(SCN)2-based NCs exhibit improved stability towards air and moisture compared to the host NCs. The doped NCs retain higher PLQY (as high as seven times) compared to the host NCs) when stored in an ambient atmosphere for more than 176 days. A novel 3D-printed multiplex color conversion layer was used to fabricate a white light-emitting diode (LED). The obtained white light shows a correlated color temperature of 6764 K, a color rendering index of 87, and luminous efficacy of radiation of 333 lm/W. In summary, this work proposes a facile route to treat sensitive lead halide perovskite NCs and to fabricate LEDs by using a low-cost large-scale 3-D printing method, which would serve as a foundation for fabricating high-quality optoelectronic devices for near future lighting technologies.


2013 ◽  
Vol 17 (05) ◽  
pp. 351-358 ◽  
Author(s):  
Mohammad Janghouri ◽  
Ezeddin Mohajerani ◽  
Mostafa M. Amini ◽  
Naser Safari

A method for obtaining red emission from an organic-light emitting diode has been developed by dissolving red and yellow dyes in a common solvent and thermally evaporating the mixture in a single furnace. Dichlorido-bis(5,7-dichloroquinolin-8-olato)tin(IV) complex ( Q2SnCl2 , Q = 5,7-dichloro-8-hydroxyquinoline) has been synthesized for using as a fluorescent material in organic light-emitting diodes (OLEDs). The electronic states HOMO (Highest Occupied Molecular Orbital)/LUMO (Lowest Occupied Molecular Orbital) energy levels explored by means of cyclic voltammetry measurements. A device with fundamental structure of ITO/PEDOT:PSS (55nm)/PVK (90nm)/ Q2SnCl2/Al (180nm) was fabricated and its electroluminescence performance at various thicknesses of light emitting layer (LEL) of Q2SnCl2 is reported. By following this step, an optimal thickness for the doping effect was also identified and explained. Finally a device with fundamental structure of ITO/PEDOT:PSS (55nm)/PVK (90nm)/meso-tetraphenylporphyrin (TPP): Q2SnCl2 (75nm)/ Al (180nm) was fabricated and its electroluminescence performance at various concentrations of dye has been investigated. It is shown that this new method is promising candidate for fabrication of low cost OLEDs at more homogeneous layer.


Author(s):  
Marco Vinicio Alban ◽  
Haechang Lee ◽  
Hanul Moon ◽  
Seunghyup Yoo

Abstract Thin dry electrodes are promising components in wearable healthcare devices. Assessing the condition of the human body by monitoring biopotentials facilitates the early diagnosis of diseases as well as their prevention, treatment, and therapy. Existing clinical-use electrodes have limited wearable-device usage because they use gels, require preparation steps, and are uncomfortable to wear. While dry electrodes can improve these issues and have demonstrated performance on par with gel-based electrodes, providing advantages in mobile and wearable applications; the materials and fabrication methods used are not yet at the level of disposable gel electrodes for low-cost mass manufacturing and wide adoption. Here, a low-cost manufacturing process for thin dry electrodes with a conductive micro-pyramidal array is presented for large-scale on-skin wearable applications. The electrode is fabricated using micromolding techniques in conjunction with solution processes in order to guarantee ease of fabrication, high device yield, and the possibility of mass production compatible with current semiconductor production processes. Fabricated using a conductive paste and an epoxy resin that are both biocompatible, the developed micro-pyramidal array electrode operates in a conformal, non-invasive manner, with low skin irritation, which ensures improved comfort for brief or extended use. The operation of the developed electrode was examined by analyzing electrode-skin-electrode impedance, electroencephalography, electrocardiography, and electromyography signals and comparing them with those measured simultaneously using gel electrodes.


2014 ◽  
Vol 61 (4) ◽  
pp. 71-78
Author(s):  
S.-J. Lee ◽  
H.-J. Park ◽  
J.-B. Park ◽  
D.-W. Jeon ◽  
J. H. Baek ◽  
...  

Author(s):  
Pamela Martinez-Vega ◽  
Araceli Lopez-Badillo ◽  
J. Luis Luviano-Ortiz ◽  
Abel Hernandez-Guerrero ◽  
Jaime G. Cervantes

Abstract The modern world progressively demands more energy; according to forecasts energy consumption will grow at an average annual rate of 3 percent. Therefore, it is necessary to purchase products or devices that are efficient and environmentally friendly. Technology in LED (Light Emitting Diode) lighting is presented as an alternative to energy saving, since LEDs have proven to be extremely efficient, have a long service life and their cost-effective ratio is very good. However, the heat emitted by the LED chip must be dissipated effectively, since the overheating of the chip reduces the efficiency and lifetime of the lamp. Therefore, heat sinks that are reliable, efficient and inexpensive should be designed and built. The present work proposes new designs for heat sinks in LED lamps, some of the models in the design of the fins refer to the Fibonacci series. The models proposed in the present work that have a significant advantage are the Type 1E Model (5.2% mass savings and better thermal efficiency of 8.33%), GR Type 1 Model (3.12% lighter and 3.33% more efficient) and the GRL Type Model (4. 51% mass savings and 5.55% thermally more efficient) compared to the Type 2 Reference Model proposed by Jang et al. [12].


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