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Light Efficiency Enhancement Technology of OLED: Fabrication of Random Nano External Light Extraction Composite Layer  

Choi, Geun Su (Dept. of Display and Semiconductor Engineering, Sunmoon University)
Jang, Eun Bi (Dept. of Display and Semiconductor Engineering, Sunmoon University)
Seo, Ga Eun (Dept. of Display and Semiconductor Engineering, Sunmoon University)
Park, Young Wook (Dept. of Display and Semiconductor Engineering, Sunmoon University)
Publication Information
Journal of the Semiconductor & Display Technology / v.21, no.3, 2022 , pp. 39-44 More about this Journal
Abstract
The light extraction technology for improving the light efficiency of OLEDs is the core technology for extracting the light inside the OLEDs to the outside. This study demonstrates a simple method to generate random nanostructures (RNSs) containing high refractive index nanoparticles to improve light extraction and viewing angle characteristics. A simple dry low-temperature process makes the nanostructured scattering layer on the polymer resin widely used in the industry. The scattering layer has the shape of randomly distributed nanorods. To control optical properties, we focused on changing the shape and density of RNSs and adjusting the concentration of high refractive index nanoparticles. As a result, the film of the present invention exhibits a perpendicular transmittance of 85% at a wavelength of 550 nm. This film was used as a scattering layer to reduce substrate mode loss and improve EL efficiency in OLEDs.
Keywords
Organic light-emitting diodes; Random nanostructure; Scattering effect; External light extraction;
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