Fabrication and optimization of transparent cathode for application in transparent oleds

Document Type : Research Paper

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Abstract

Organic light-emitting diodes (OLED), which are fabricated based on organic materials, are a new class of lighting sources with many advantage in comparison to common light-emitting diodes. One of these promising depictions of OLEDs is their capability for fabrication of transparent displays in which the device possesses a transparency up to 70% during the off-state. In these types of displays, all the components such as substrate, the anode, the organic-polymer layers, and the cathode electrode are transparent and the emission can leave the device from the both sides. Recently, transparent OLEDs have attracted a lot of attention due to their exceptional applications such as transparent flat-panel displays, car front windows, and smart windows.The aim of the present research is to fabrication a transparent cathode composing of Ca , Ag by constant thickness of 20 nm and 10 nm and ZnS Dielectric coating layer with different thickness of 20,25,30,40 nm for used in the transparent organic light emitting diodes. The experimental ZnS thickness are obtained to be 25 nm. Optical transparency of 85% and low reflection of 10.50% in visible region and low surface electrical resistance of 8.6 ohm/square in Ca(20nm)/Ag(10nm)/ZnS (25nm) structure is obtained which seem to be applicable in transparent oleds

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References

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Iranian Journal of Applied Physics
Volume 6, Issue 1
January 2016
Pages 97-107

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History

  • Receive Date: 10 November 2015
  • Revise Date: 08 February 2016
  • Accept Date: 03 October 2016

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