skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Enhanced Light Extraction from OLEDs Fabricated on Patterned Plastic Substrates

Journal Article · · Advanced Optical Materials
 [1];  [1];  [2];  [1];  [3];  [4];  [5];  [6]; ORCiD logo [1];  [7]
  1. Ames Lab. and Iowa State Univ., Ames, IA (United States). Physics & Astronomy Dept.
  2. Iowa State Univ., Ames, IA (United States). Electrical and Computer Engineering Dept.
  3. Ames Lab. and Iowa State Univ., Ames, IA (United States); Iowa State Univ., Ames, IA (United States). Electrical and Computer Engineering Dept., and Microelectronics Research Center
  4. Ames Lab. and Iowa State Univ., Ames, IA (United States). Physics & Astronomy Dept.; Iowa State Univ., Ames, IA (United States). Electrical and Computer Engineering Dept., and Microelectronics Research Center
  5. MicroContinuum, Inc., Cambridge, MA (United States)
  6. Trovato Manufacturing, Inc., Victor, NY (United States)
  7. Iowa State Univ., Ames, IA (United States). Electrical and Computer Engineering Dept., and Microelectronics Research Center

Abstract A key scientific and technological challenge in organic light‐emitting diodes (OLEDs) is enhancing the light outcoupling factor η out , which is typically <20%. This paper reports experimental and modeling results of a promising approach to strongly increase η out by fabricating OLEDs on novel flexible nanopatterned substrates that result in a >2× enhancement in green phosphorescent OLEDs (PhOLEDs) fabricated on corrugated polycarbonate (PC). The external quantum efficiency (EQE) reaches 50% (meaning η out ≥50%); it increases 2.6x relative to a glass/ITO device and 2× relative to devices on glass/poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) or flat PC/PEDOT:PSS. A significant enhancement is also observed for blue PhOLEDs with EQE 1.7× relative to flat PC. The corrugated PC substrates are fabricated efficiently and cost‐effectively by direct room‐temperature molding. These substrates successfully reduce photon losses due to trapping/waveguiding in the organic+anode layers and possibly substrate, and losses to plasmons at the metal cathode. Focused ion beam gauged the conformality of the OLEDs. Dome‐shaped convex nanopatterns with height of ∼280–400 nm and pitch ∼750–800 nm were found to be optimal. Substrate design and layer thickness simulations, reported first for patterned devices, agree with the experimental results that present a promising method to mitigate photon loss paths in OLEDs.

Research Organization:
Ames Laboratory (AMES), Ames, IA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES)
Grant/Contract Number:
SC0011337; EE0007621; AC02-07CH11358; DE‐SC0011337; DE‐EE0007621
OSTI ID:
1425476
Alternate ID(s):
OSTI ID: 1415661
Report Number(s):
IS-J-9585
Journal Information:
Advanced Optical Materials, Vol. 6, Issue 4; ISSN 2195-1071
Publisher:
WileyCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 25 works
Citation information provided by
Web of Science

References (46)

Analysis of the external and internal quantum efficiency of multi-emitter, white organic light emitting diodes journal October 2012
Outcoupling-Enhanced Flexible Organic Light-Emitting Diodes on Ameliorated Plastic Substrate with Built-in Indium–Tin-Oxide-Free Transparent Electrode journal June 2015
Light extraction from OLEDS with (high) index matched glass substrates conference June 2008
High-Efficiency Solution-Processed Small Molecule Electrophosphorescent Organic Light-Emitting Diodes journal July 2011
Importance of indium tin oxide surface acido basicity for charge injection into organic materials based light emitting diodes journal June 2000
Blue organic light-emitting diodes realizing external quantum efficiency over 25% using thermally activated delayed fluorescence emitters journal March 2017
Quantification of energy loss mechanisms in organic light-emitting diodes journal December 2010
Holographic Embossing at Polaroid: The Polaform Process conference June 1986
Improvement of output coupling efficiency of organic light-emitting diodes by backside substrate modification journal March 2000
Efficient and Flexible ITO-Free Organic Solar Cells Using Highly Conductive Polymer Anodes journal November 2008
Organic light-emitting devices (OLEDs) and OLED-based chemical and biological sensors: an overview journal June 2008
Enhanced light out-coupling of organic light-emitting devices using embedded low-index grids journal July 2008
Highly Conductive and Transparent PEDOT:PSS Films with a Fluorosurfactant for Stretchable and Flexible Transparent Electrodes journal November 2011
A Transparent, Smooth, Thermally Robust, Conductive Polyimide for Flexible Electronics journal November 2015
Modifications of the exciton lifetime and internal quantum efficiency for organic light-emitting devices with a weak/strong microcavity journal November 2007
Simple routes for improving polythiophene:fullerene-based organic solar cells journal February 2011
Enhanced Outcoupling in Organic Light-Emitting Diodes via a High-Index Contrast Scattering Layer journal August 2015
Extremely Efficient Indium-Tin-Oxide-Free Green Phosphorescent Organic Light-Emitting Diodes journal July 2012
Enhanced light extraction from organic light-emitting devices using a sub-anode grid journal October 2015
Surface morphology, optical properties and conductivity changes of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) by using additives journal June 2013
Microcavity-Free Broadband Light Outcoupling Enhancement in Flexible Organic Light-Emitting Diodes with Nanostructured Transparent Metal–Dielectric Composite Electrodes journal December 2015
Measuring the internal luminescence quantum efficiency of OLED emitter materials in electrical operation conference February 2010
Continuous manufacturing of thin cover sheet optical media conference August 1992
Improved light out-coupling in organic light emitting diodes employing ordered microlens arrays journal March 2002
Simulation of light emission from thin-film microcavities journal January 1998
Highly Conductive PEDOT:PSS Electrode with Optimized Solvent and Thermal Post-Treatment for ITO-Free Organic Solar Cells journal February 2011
Analyses of optical out-coupling of organic light-emitting devices having micromesh indium tin oxide and conducting polymer as composite transparent electrode journal January 2016
Emerging Transparent Electrodes Based on Thin Films of Carbon Nanotubes, Graphene, and Metallic Nanostructures journal February 2011
Enhancement and inhibition of electromagnetic radiation in plane-layered media IPlane-wave spectrum approach to modeling classical effects journal January 1997
Fourfold power efficiency improvement in organic light-emitting devices using an embedded nanocomposite scattering layer journal June 2012
Highly Conductive Polymer Anodes as Replacements for Inorganic Materials in High-Efficiency Organic Light-Emitting Diodes journal February 2007
Polarization Conversion in Surface-Plasmon-Coupled Emission from Organic Light-Emitting Diodes Using Spontaneously Formed Buckles journal January 2011
Highly efficient and stable tandem organic light-emitting devices based on HAT-CN/HAT-CN:TAPC/TAPC as a charge generation layer journal January 2015
Electroluminescence emission pattern of organic light-emitting diodes: Implications for device efficiency calculations journal July 2000
Highly efficient phosphorescent emission from organic electroluminescent devices journal September 1998
High-Performance Flexible Organic Light-Emitting Diodes Using Embedded Silver Network Transparent Electrodes journal November 2014
Soft holographic interference lithography microlens for enhanced organic light emitting diode light extraction journal January 2011
Broadband Light Out-Coupling Enhancement of Flexible Organic Light-Emitting Diodes Using Biomimetic Quasirandom Nanostructures journal October 2014
Efficiency and rate of spontaneous emission in organic electroluminescent devices journal March 2012
Indium-tin-oxide-free tris(8-hydroxyquinoline) Al organic light-emitting diodes with 80% enhanced power efficiency journal October 2011
Highly enhanced phosphorescent organic light-emitting diodes with cesium fluoride doped electron injection layer conference September 2015
High Quantum Efficiency in Organic Light-Emitting Devices with Iridium-Complex as a Triplet Emissive Center journal December 1999
The Morphological Power of Soap: How Surfactants Lower the Sheet Resistance of PEDOT:PSS by Strong Impact on Inner Film Structure and Molecular Interface Orientation journal February 2016
On the mechanism of conductivity enhancement in poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) film through solvent treatment journal November 2004
Very high-efficiency green organic light-emitting devices based on electrophosphorescence journal July 1999
Organic Light-Emitting Devices conference January 2005

Cited By (10)

Sodium Ion Modifying In Situ Fabricated CsPbBr 3 Nanoparticles for Efficient Perovskite Light Emitting Diodes journal August 2019
Enhanced outcoupling in down-conversion white organic light-emitting diodes using imprinted microlens array films with breath figure patterns text January 2018
Recent Developments in Flexible Organic Light-Emitting Devices journal October 2018
Light Management with Patterned Micro‐ and Nanostructure Arrays for Photocatalysis, Photovoltaics, and Optoelectronic and Optical Devices journal April 2019
Thermally Activated Delayed Fluorescence Emitters for Deep Blue Organic Light Emitting Diodes: A Review of Recent Advances journal March 2018
Emerging Self‐Emissive Technologies for Flexible Displays journal October 2019
Self-catalytic-grown SnO x nanocones for light outcoupling enhancement in organic light-emitting diodes journal January 2020
Surface Plasmonic‐Assisted Photocatalysis and Optoelectronic Devices with Noble Metal Nanocrystals: Design, Synthesis, and Applications journal December 2019
Enhanced outcoupling in down-conversion white organic light-emitting diodes using imprinted microlens array films with breath figure patterns journal January 2019
Enhanced outcoupling in down-conversion white organic light-emitting diodes using imprinted microlens array films with breath figure patterns text January 2018

Figures / Tables (12)