한국전기전자재료학회논문지 (Journal of the Korean Institute of Electrical and Electronic Material Engineers)

  • 제22권6호
  • /
  • Pages.512-515
  • /
  • 2009
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  • 1226-7945(pISSN)
  • /
  • 2288-3258(eISSN)
한국전기전자재료학회 (The Korean Institute of Electrical and Electronic Material Engineers)
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부분 도핑을 이용한 청색 인광 OLEDs의 전기 및 광학적 특성

Electrical and Optical Properties of Partially Doped Blue Phosphorescent OLEOs

  • 서유석 (순천향대학교 신소재공학과) ;
  • 문대규 (순천향대학교 신소재공학과)
  • 발행 : 2009.06.01
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초록

We have fabricated blue phosphorescent organic light emitting diodes (PHOLEDs) using a 3,5'-N,N'-dicarbazole-benzene (mCP) host and iridium (III) bis[(4,6-difluorophenyl)-pyridinato-N,$C^{2'}$] picolinate (Flrpic) guest materials, The Flrpic was partially doped into the mCP host layer, for investigating recombination zone, current efficiency, and emission characteristics of the blue PHOLEDs. The recombination of electrons and holes takes place inside the mCP layer adjacent to the mCP/hole blocking layer interface. The best current efficiency was obtained in a device with an emission layer structure of mCP (10 nm)/mCP:Flrpic (20 nm, 10%). The high current efficiency in this device was attributed to the confinement of Ffrpic triplet excitons by the undoped mCP layer with high triplet energy, which blocks diffusion of Ffrpic excitons to the adjacent hole transport layer with a lower triplet energy.

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참고문헌

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