Electrical and Optical Properties of Red Phosphorescent Top Emission OLEDs with Transparent Metal Cathodes

투명 금속 음극을 이용한 전면발광 적색 인광 OLEDs의 전기 및 광학적 특성

  • 김소연 (순천향대학교 신소재공학과) ;
  • 하미영 (순천향대학교 신소재공학과) ;
  • 문대규 (순천향대학교 신소재공학과) ;
  • 이찬재 (전자부품연구원 디스플레이센터) ;
  • 한정인 (전자부품연구원 디스플레이센터)
  • Published : 2007.09.01


We have developed red phosphorescent top emission organic light-emitting diodes with transparent metal cathodes deposited by using thermal evaporation technique. Phosphorescent guest molecule, BtpIr(acac), was doped in host CBP for the red phosphorescent emission, Ca/Ag, Ba/Ag, and Mg/Ag double layers were used as cathode materials of top emission devices, which were composed of glass/Ni/2TNATA(15 nm)/${\alpha}$-NPD(35 nm)/CBP:BtpIr(acac)(40 nm, 10%)/BCP(5 nm)/$Alq_3$(5 nm)/cathodes. The optical transparencies of these metal cathodes strongly depend on underlying Ca, Ba, and Mg layers. These layers also strongly affect the electrical conduction and emission properties of the red phosphorescent top emission devices.



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