Journal of IKEEE (전기전자학회논문지)

Institute of Korean Electrical and Electronics Engineers (한국전기전자학회)
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Spike type high-transmittance external light extraction film imprinted with P(VDF-TrFE) mold with island surface structure

Island 표면구조의 P(VDF-TrFE) 몰드를 임프린트한 Spike 형태의 고투과성 외부광추출 필름

  • Sung, Baeksang (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Cho, Jae-Hyeok (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Lim, Young-Ji (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Gasonoo, Akpeko (RIPE & 3D Printing, Hanbat Nat'l Univ.) ;
  • Lee, Hyunah (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Lee, Jangwon (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Woo, Seungwan (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Kim, Dongsoo (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Lee, Jae-Hyun (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Kim, Min-Hoi (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Lee, Jonghee (Department of Creative Convergence Engineering, Hanbat National University)
  • Received : 2021.05.10
  • Accepted : 2021.06.25
  • Published : 2021.06.30
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Abstract

In this study, a method for improving the light extraction efficiency of organic light emitting diodes was presented using the polymer Poly(vinylidenefluoride-co-trifluoroethylene) [P(VDF-TrFE)] having an island surface structure after annealing. Polydimethylsiloxane (PDMS) imprinted on the island-structured P(VDF-TrFE) surface has a spike structure, which improves the external light extraction efficiency aroud 20%. It was confirmed that the produced film showed a low haze characteristic of 8.2, and the Current and external quantum efficiency could be improved without pixel blur due to the excellent transmittance of 93.4%.

본 연구에서는 열처리 후 Island 표면 구조를 가지는 고분자 Poly(vinylidenefluoride-co-trifluoroethylene) [P(VDF-TrFE)]를 사용하여 유기 발광 다이오드의 광추출 효율을 향상시키기 위한 방법을 제시하였다. Island 구조의 P(VDF-TrFE) 표면 위에 임프린트한 polydimethylsiloxane (PDMS)는 Spike 구조를 띄고 이를 통해 전류 및 외부양자 효율을 약 20%을 향상시켰다. 제작된 필름은 8.2의 낮은 Haze특성을 보이며, 93.4% 우수한 투과도 특성으로 인해 Pixel blur 없이 광효율을 향상시킬 수 있음을 확인하였다.

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 2019R1I1A3A01056075), and by Korea Institute for Advancement of Technology(KIAT) grant funded by the Korea Government(MOTIE) (P0012744, The Competency Development Program for Industry Specialist).

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