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

The Korean Institute of Electrical and Electronic Material Engineers (한국전기전자재료학회)
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Effects of Electron Transport Layers on Electrical and Optical Characteristics of Blue Phosphorescent Organic Light Emitting Diodes

전자수송층이 청색 인광 OLED의 전기 및 광학적 특성에 미치는 영향

  • 서원규 (순천향대학교 디스플레이신소재공학과) ;
  • 문대규 (순천향대학교 디스플레이신소재공학과)
  • Published : 2009.04.01
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Abstract

We have developed blue-emitting phosphorescent organic light emitting diodes (OLEDs) using 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and tris (8-quinolinolato)aluminum ($Alq_3$) electron transport layers. As blue dopant and host materials, bis[(4,6-di-fluorophenyl)-pyridinate-N,C2']picolinate (FIrpic) and N,N'-dicarbazolyl-3,5-benzene (mCP) were used, respectively. The driving voltage, current efficiency and emission characteristics of devices were investigated. While the driving voltage was about $1{\sim}2$ V lower in the device with an $Alq_3$ layer, the current efficiency was about 66 % higher in the device with BCP electron transport layer. the blue phosphorescent OLED with BCP layer exhibited higher purity of color, resulting from a relatively weak electroluminescence intensity at 500 nm.

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References

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