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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

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.

Keywords

organic light emitting diodes;hole injection layer;efficiency

Acknowledgement

Supported by : 중소기업청

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