Journal of the Semiconductor & Display Technology (반도체디스플레이기술학회지)

The Korean Society Of Semiconductor & Display Technology (한국반도체디스플레이기술학회)
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Light Efficiency Enhancement Technology of OLED: Fabrication of Random Nano External Light Extraction Composite Layer

OLED의 광 효율 향상 기술: 랜덤 나노 외부 광 추출 복합 층 제작

  • 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)
  • 최근수 (선문대학교 디스플레이반도체공학과) ;
  • 장은비 (선문대학교 디스플레이반도체공학과) ;
  • 서가은 (선문대학교 디스플레이반도체공학과) ;
  • 박영욱 (선문대학교 디스플레이반도체공학과)
  • Received : 2022.08.24
  • Accepted : 2022.09.21
  • Published : 2022.09.30
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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

Acknowledgement

이 연구는 2020년도 정부(과학기술정보통신부)의 재원으로 한국연구재단의 지원 (No. 2020R1C1C1013567)과 2022년도 교육부의 재원으로 한국연구재단의 지원을 받아 수행된 지자체-대학 협력기반 지역혁신 사업(2021RIS-004, 2022H-01-02-09-002)으로 수행된 결과입니다. 또한 선문대학교 차세대반도체기술센터의 분석지원에 감사드립니다.

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