Skip to main content
Log in

Effect of the flow rate of oxygen and hydrogen gases on the characteristics of organic light emitting diodes with Al-doped ZnO anodes

  • Published:
Electronic Materials Letters Aims and scope Submit manuscript

Abstract

We investigate the effect of the flow rate of oxygen and hydrogen gases on the characteristics of OLEDs (organic light emitting diodes) with Al-doped ZnO (AZO) anodes. The AZO thin films are deposited by radio frequency (RF) magnetron sputtering under different ambient gases (Ar, Ar + O2, and Ar + H2) at 300°C. To investigate the influences of the ambient gases, the flow rate of oxygen and hydrogen in argon was varied from 0.1 sccm to 5 sccm. The AZO thin films were preferentially oriented to the (002) direction regardless of the ambient gase used. The electrical resistivity of the AZO thin films increased with increasing O2 flow rates, whereas the electrical resistivity decreased sharply under an Ar + H2 atmosphere and was nearly the same regardless of the H2 flow rate used. The change of electrical resistivity with changes in the ambient gas composition was mainly interpreted in terms of the charge carrier concentration rather than the charge carrier mobility. All the films showed an average transmittance of over 85% in the visible range. The optical band gap of the AZO films increased with increasing H2 flow rates, whereas the optical band gap of the AZO films deposited in an O2 atmosphere decreased with increasing O2 flow rates. The current density and the luminance of the OLED devices with AZO thin films deposited in 5 sccm of H2 ambient gas were the highest among all the films. The optical band gap energy of AZO thin films plays a major role in OLED device performance, especially the current density and luminance.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. K. Tominaga, T. Ueda, T. Ao, M. Kataoka, and I. Mori, Thin Solid Films 281–282, 194 (1996).

    Article  Google Scholar 

  2. Y. Hoshi, H. Kato, and K. Funatsu, Thin Solid Films 445, 245 (2003).

    Article  CAS  Google Scholar 

  3. K. K. Kim, H. Kim, S. N. Lee, and S. Cho, Electron. Mater. Lett. 7, 145 (2011).

    Article  CAS  Google Scholar 

  4. N. Taga, M. Maekawa, Y. Shigesato, I. Yasui, M. Kamei, and T. E. Haynes, Jpn. J. Appl. Phys. 37, 6524 (1998).

    Article  CAS  Google Scholar 

  5. C. N. de Carvalho, A. M. B. do Rego, A. Amaral, P. Brogueira, and G. Lavareda, Surface and Coatings Technology 124, 70 (2000).

    Article  Google Scholar 

  6. X. Jiang, F. L. Wong, M. K. Fung, and S. T. Lee, Appl. Phys. Lett. 83, 1875 (2003).

    Article  CAS  Google Scholar 

  7. J. Hu and R. G. Gordon, J. Appl. Phys. 71, 880 (1992).

    Article  CAS  Google Scholar 

  8. F. K. Shan and Y. S. Yu, J. Eur. Ceram. Soc. 24, 1869 (2004).

    Article  CAS  Google Scholar 

  9. D. Horwat, Thin Solid Flms 515, 5444 (2007).

    Article  CAS  Google Scholar 

  10. W. Liu, G. Du, Y. Sun, Y. Xu, T. Yang, X. Wang, Y. Chang, and F. Qiu, Thin Solid Flms 515, 3057 (2007).

    Article  CAS  Google Scholar 

  11. K. H. Yoon, J. W. Choi, and D. H. Lee, Thin Solid Films 302, 116 (1997).

    Article  CAS  Google Scholar 

  12. N. Oka, K. Kimura, T. Yagi, N. Taketoshi, T. Baba, and Y. Shigesato, J. Appl. Phys. 111, 093701 (2112).

    Article  Google Scholar 

  13. J. Jia, A. Takasaki, N. Oka, and Y. Shigesato, J. Appl. Phys. 112, 013718 (2112).

    Article  Google Scholar 

  14. D. H. Hwang, H. H. Ahn, K. N. Hui, K. S. Hui, and Y. G. Son, J. Ceram. Proc. Res. 12, 150 (2011).

    Google Scholar 

  15. D. Xu, Z. Deng, Y. Xu, J. Xiao, C. Liang, Z. Pei, and C. Sun, Phys. Lett. A 346, 148 (2005).

    Article  CAS  Google Scholar 

  16. X. T. Hao, L. W. Tan, K. S. Ong, and F. Zhu, J. Cryst. Growth 287, 44 (2006).

    Article  CAS  Google Scholar 

  17. R. Das, K. Adhikary, and S. Ray, Appl. Surf. Sci. 253, 6068 (2007).

    Article  CAS  Google Scholar 

  18. J. Tauc, R. Grigorovichi, and A. Vancu, Phys. Status Solidi 15, 627 (1966).

    Article  CAS  Google Scholar 

  19. D. H. Oh, Y. S. No, S. Y. Kim, W. J. Cho, J. Y. Kim, and T. W. Kim, J. Ceram. Proc. Res. 12, 488 (2011).

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Kyu-Mann Lee.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Han, SH., Jo, DB. & Lee, KM. Effect of the flow rate of oxygen and hydrogen gases on the characteristics of organic light emitting diodes with Al-doped ZnO anodes. Electron. Mater. Lett. 9 (Suppl 1), 43–48 (2013). https://doi.org/10.1007/s13391-013-3178-z

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s13391-013-3178-z

Keywords

Navigation