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

The Korean Institute of Electrical and Electronic Material Engineers (한국전기전자재료학회)
권호 표지
DOI QR코드

DOI QR Code

Electrical Properties of OLEDs due to the Hole-size of Crucible Boat and Deposition Rate of Hole Transport Layer

Crucible Boat 홀 크기와 정공 수송층 증착속도에 따른 유기밭광 다이오드의 전기적 특성

  • 김원종 (광운대학교 전기응용연구실) ;
  • 신현택 (광운대학교 전기응용연구실) ;
  • 신종열 (삼육대학교 카메카트로닉스학과) ;
  • 홍진웅 (광운대학교 전기응용연구실)
  • Published : 2009.01.01
Download PDF
⟨ Previous Next ⟩

Abstract

In the structure of ITO/N,N'-diphenyl-N,N' bis (3-methylphenyl)-1,1'-biphenyl-4,4'-diamine(TPD)/tris (8-hydroxyquinoline)aluminum($Alq_3$)/Al device, we studied the efficiency improvement of organic light-emitting diodes due to variation of deposition rate of hole transport layer (TPD) materials using hole-size of crucible boat. The thickness of TPD and $Alq_3$ was manufactured 40 nm, 60 nm, respectively under a base pressure of $5{\times}10^{-6}$ Torr using a thermal evaporation. The $Alq_3$ used for an electron-transport and emissive layer were evaporated to be at a deposition rate of $2.5\;{\AA}/s$. When the deposition rate of TPD increased from 1.5 to $3.0\;{\AA}/s$, we studied the efficiency improvement of TPD using the hole-size of crucible is 1.0 mm. When the deposition rate of TPD is $2.5\;{\AA}/s$, we found that the average roughness is rather smoother, the luminous efficiency the external quantum efficiency is superior to the others. Compared to the two from the devices made with the deposition rate of TPD is $2.0\;{\AA}/s$ and $3.0\;{\AA}/s$, the external quantum efficiency was improved by four-times and two-times, respectively.

Keywords

References

  1. G. B. Blanchet, Y. L. Loo, J. A. Rogers, F. Gao, and C. R. Fincher, 'Large area, high resolution, dry printing of conducting polymers for organic electronics', Appl. Phys. Lett., Vol. 82, p. 463, 2003 https://doi.org/10.1063/1.1533110
  2. H. Mu, H. Shen, and D. Klotzkin, 'Dependence of film morphology on deposition rate in ITO/TPD/$Alq_3$/Al organic luminescent diodes', Solid-State Electronics, Vol. 48, p. 2085, 2004 https://doi.org/10.1016/j.sse.2004.05.067
  3. W. J. Kim, J. H. Yang, T. Y. Kim, J. Jeong, Y. H. Lee, H. Y. Park, T. W. Kim, and J. W. Hong, 'Efficiency improvement of organic light-emitting diodes depending on thickness of hole injection materials', Trans. EEM, Vol. 6, No. 5, p. 233, 2005
  4. Y. H. Lee, W. J. Kim, T. Y. Kim, J. Jeong, H. D. Park, T. W. Kim, and J. W. Hong, 'Electrical characteristics and efficiency of organic light-emitting diodes depending on hole-injection layer', Curr. Appl. Phys., Vol. 7, p. 409, 2007 https://doi.org/10.1016/j.cap.2006.09.021
  5. T. W. Choi and S. C. Yoo, 'Electrical and mechanical properties of ceramics', J. Mater. Sci., Vol. 15, No. 1, p. 10, 2001
  6. S. K. Kim, J. W. Hong, and T. W. Kim, 'Current voltage characteristics of organic light emitting diodes with a variation of temperature', Trans. KIEE., Vol. 51, No. C-7, p. 322, 2002
  7. C. W. Tang and S. A. VanSlyke, 'Organic electroluminescent diodes', Appl. Phys. Lett., Vol. 51, p. 913, 1987 https://doi.org/10.1063/1.98799
  8. W. J. Kim, Y. H. Lee, J. H. Yang, T. Y. Kim T. W. Kim, and J. W. Hong, 'Electrical characteristics and luminous efficiency of OLEDs depending on the hole injectioon layer', ME&D-16, p. 85, 2005
  9. W. J. Kim, Y. H. Lee, T. Y. Kim, T. W. Kim, and J. W. Hong, 'Dependence of efficiency improvement and operating- voltage reduction of OLEDs on Thickness Variation in the PTFE Hole-injection Layer', J. Korean. Phys. Soc., Vol. 51, No. 3, p. 1007, 2007 https://doi.org/10.3938/jkps.51.1007
  10. Y. H. Lee, W. J. Kim, T. Y. Kim, T. W. Kim, and J. W. Hong, 'Electrical and optical characteristics of organic light- emitting diodes for various thickness of the PTFE Layer', J. Korean. Phys. Soc., Vol. 51, No. 3, p. 1016, 2007 https://doi.org/10.3938/jkps.51.1016
  11. 김원종, 홍진웅, 'Crucible boat의 홀 크기에 따른 유기발광소자의 효율개선', 전기전자재료학회논문지, 21권, 6호, p. 569, 2008 https://doi.org/10.4313/JKEM.2008.21.6.569
  12. I. D. Parker, 'Device characteristics in polymer light-emitting diodes', J. Appl. Phys., Vol. 75, p. 1656, 1994 https://doi.org/10.1063/1.356350
  13. Y. Qiu and D. Q. Zhang, 'Dependence of the performance of the organic electro luminescent devices upon the deposition rate of organic thin films', Synth. Metals., Vol. 110, p. 241, 2000 https://doi.org/10.1016/S0379-6779(99)00300-8
  14. C. Qiu, H. Chen, and M. Wong, 'Dependence of the current and power efficiencies of organic light-emitting diode on the thickness of the constituent organic layers', IEEE T Electron Dev., Vol. 48, No. 9, p. 2131, 2001 https://doi.org/10.1109/16.944206