Electrical and Optical Properties of Top Emission OLEDs with Ba/Ag Transparent Cathodes

Ba/Ag 투명 음극을 이용한 전면발광 OLEDs의 전기 및 광학적 특성

  • 문대규 (순천향대학교 신소재공학과) ;
  • 이찬재 (전자부품연구원 디스플레이센터) ;
  • 한정인 (전자부품연구원 디스플레이센터)
  • Published : 2006.09.01


We have fabricated top omission organic light emitting diodes with transparent Ba/Ag double layer cathodes deposited by using thermal evaporation method. The device structure was $glass/Ni(200nm)/2-TNATA(15 nm)/{\alpha}-NPD(15nm)Al_{q3}:C545T\;(1%,\;35nm)/BCP(5nm)/Ba(10nm)/Ag(8nm)$. The optical transmittance of the Ba(10 nm)/Ag(8 nm) layer was over 60 % in the visible wavelength region. The maximum efficiency of the device was $13.7\;cd/A\;at\;0.69\;mA/cm^{2}$ and the efficiency of over 10 cd/A was achieved at wide range of current densities and luminances.


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