전기전자학회논문지 (Journal of IKEEE)

  • 제24권3호
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  • Pages.699-705
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  • 2020
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  • 1226-7244(pISSN)
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  • 2288-243X(eISSN)
한국전기전자학회 (Institute of Korean Electrical and Electronics Engineers)
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고분자 정공수송층에 용액 공정 도핑법을 적용한 인광 유기전기발광소자

Solution processed doping to the polymer hole transporting layer for phosphorescent organic light-emitting diodes

  • Sung, Baeksang (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Lee, Jangwon (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Lee, Seung-Hoon (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Yoo, Jae-Min (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Lee, Jae-Hyun (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Lee, Jonghee (Department of Creative Convergence Engineering, Hanbat National University)
  • 투고 : 2020.07.10
  • 심사 : 2020.09.17
  • 발행 : 2020.09.30
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초록

본 연구에서는 유기전기발광소자의 전기적 특성을 향상시키기 위한 방법으로, 용액공정 도핑법이 도입된 고분자 poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4′-(N-(4-sec-butylphenyl)diphenylamine)] (TFB)기반의 정공수송층을 제안하였다. 정공수송층 소재 TFB 용액 내에 1,4,5,8,9,11-hexaazatriphenylene hexacarbonitrile (HAT-CN)를 3 wt% 도핑을 하여 정공수송층의 전기적 특성을 향상 시켰다. 이를 통해 HAT-CN이 도핑된 TFB을 이용한 유기전기발광소자에서는 향상된 정공수송층의 전도도를 통해 동일 구동 전압 시 전류 밀도와 휘도가 증가하였고, 점등 개시 전압이 13V에서 9V로 줄어드는 것을 확인하였다. 또한, 도핑법이 적용되지 않은 기준 소자 대비 최대 외부양자효율이 3.6%에서 10.8%로 약 3배 향상 되는 것을 확인하였다.

In this study, a facial way to enhance the electrical properties of organic light-emitting diodes (OLEDs) via the solution process doping method based on the poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl) diphenylamine)] (TFB) as a hole transporting layer (HTL) is demonstrated. In the TFB solution of the hole transport material, 1,4,5,8,9,11-hexaazatriphenylene hexacarbonitrile (HAT-CN) was doped by 3 wt% to improve the electrical properties of the HTL. According, the OLED with HAT-CN doped TFB showed the increased current density and luminance at the same driving voltage on behalf of the improved conductivity of HTL, and the reduced turn-on voltage from 13 V to 9 V. Furthermore, the maximum external quantum efficiency was dramatically increased three times from 3.6 to 10.8 % compared to the reference device without appling doping methode.

키워드

참고문헌

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