Applied Chemistry for Engineering (공업화학)

The Korean Society of Industrial and Engineering Chemistry (한국공업화학회)
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Efficient Green Phosphorescent OLEDs with Hexaazatrinaphthylene Derivatives as a Hole Injection Layer

Hexaazatrinaphthylene 유도체를 정공 주입층으로 사용한 고효율 녹색 인광 OLEDs

  • Lee, Jae-Hyun (Department of Creative Convergence Engineering, Hanbat National University) ;
  • Lee, Jonghee (OLED Research Center, Electronics and Telecommunications Research Institute)
  • 이재현 (국립한밭대학교 창의융합학과) ;
  • 이종희 (한국전자통신연구원 OLED 연구센터)
  • Received : 2015.10.05
  • Accepted : 2015.10.19
  • Published : 2015.12.10
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Abstract

Organic light emitting diodes (OLEDs) are regarded as the next generation display and solid-state lighting due to their superb achievements from extensive research efforts on improving the efficiency and stability of OLEDs in addition to developing new materials. Herein, efficient green phosphorescent OLEDs were obtained by using hexaazatrinaphthylene (HAT) derivatives as a hole injection layer. External quantum and current efficiencies of OLEDs were enhanced from 8.8% and 30.8 cd/A to 13.6% and 47.7 cd/A, respectively by inserting a thin layer of HAT derivatives between the ITO and hole transporting layer. The enhancement of OLEDs was found to be originated from the inserted HAT derivatives, which resulted in the optimized hole-electron balance inside the emission layer.

유기발광다이오드(organic light emitting diodes, OLEDs)는 높은 효율, 안정성, 신물질 개발과 같은 연구들을 바탕으로 차세대 디스플레이 및 조명으로써의 높은 기술력과 학문적 발전을 달성하였다. 본 논문에서는 hexaazatrinaphthylene (HAT) 유도체들을 OLEDs 소자의 정공주입층으로 사용하여 제작된 고효율의 녹색 인광 OLEDs 소자의 특성을 연구하였다. Indium Tin Oxide (ITO)전극과 정공수송층 사이에 삽입된 박막의 HAT 유도체층은 $1,000cd/m^2$의 구동 조건에서 OLEDs 소자의 외부양자효율을 기존의 8.8%에서 13.6%로, 전류효율을 30.8 cd/A에서 47.7 cd/A로 각각 향상시켰다. 삽입된 HAT 유도체층은 발광층 내부에서 최적화된 전자-정공의 균형을 이루게 하여 소자의 효율 향상에 기여하였다.

Keywords

References

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