Journal of IKEEE (전기전자학회논문지)

Institute of Korean Electrical and Electronics Engineers (한국전기전자학회)
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External light extraction film for organic light-emitting diodes using AAO template

양극 산화 알루미늄 (AAO) 템플릿을 이용한 유기전기발광소자용 외부광추출 필름

  • Jinhwa Kim (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Baeksang Sung (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Sora Han (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Dasol Kim (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Seung Wan Woo (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Jooho Lee (Department of Creative Convergence Engineering, Hanbat National University) ;
  • So-Young Boo (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Hyun-Bin Kim (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Jae-yong Park (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Somi Park (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Seung-Yo Baek (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Chul Woong Joo (Reality Display Research Section, Electronics and Telecommunications Research Institute (ETRI)) ;
  • Jae-Hyun Lee (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Jonghee Lee (Department of Creative Convergence Engineering, Hanbat National University)
  • Received : 2023.04.21
  • Accepted : 2023.06.06
  • Published : 2023.06.30
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Abstract

In this study, an external light extraction method to improve efficiency of organic light emitting diodes was presented using an anodic aluminum oxide (AAO) template having nano-sized spherical structures. The imprinted polydimethylsiloxane on top of the AAO surface has nano-sized halfsphere shape. Therefore, when this film attached on the substrate of organic light-emitting diodes, the external quantum efficiency is improved up to 16.8%. The produced film shows a high transmittance of over 90% and a low haze value, which results in efficiency enhancement with very marginal pixel blur.

본 연구에서는 나노 크기의 반구 형태를 가지는 양극 산화 알루미늄(AAO) 템플릿을 이용하여 유기 발광 다이오드의 외부 광효율을 향상시키기 위한 방법을 제시하였다. 나노 크기의 반구 형태 필름은 AAO 템플릿 상부에 polydimethylsiloxane를 임프린팅하여 제작하였다. 임프린팅 된 필름은 나노 크기의 반구 구조를 가지며, 이를 유기발광다이오드에 적용시 외부 양자 효율을 최대 16.8%까지 향상시켰다. 제작된 필름은 90% 이상의 높은 투과율과 낮은 흐림도를 보여 이를 통해 pixel blur 현상 없이 광효율을 향상시킬 수 있음을 확인했다.

Keywords

Acknowledgement

The authors acknowledge financial support from the Basic Science Research program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2018R1A6A1A03026005 and 2022R1A2C1004286), and by Korea Institute for Advancement of Technology(KIAT) grant funded by the Korea Government(MOTIE) (P0012744, The Competencyency Development Program for Industry Specialist).

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