OSA's Digital Library

Journal of Display Technology

Journal of Display Technology

| A JOINT IEEE/OSA PUBLICATION

  • Vol. 2, Iss. 4 — Dec. 1, 2006
  • pp: 341–346

Measurement of Electron Mobility in Alq3 From Optical Modulation Measurements in Multilayer Organic Light-Emitting Diodes

Haichuan Mu and David Klotzkin

Journal of Display Technology, Vol. 2, Issue 4, pp. 341-346 (2006)


View Full Text Article

Acrobat PDF (328 KB)





Browse Journals / Lookup Meetings

Browse by Journal and Year


   


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools

Share
Citations
  • Export Citation/Save Click for help

Abstract

The dynamic characteristics of multilayer organic light-emitting diodes (OLEDs) determine the refresh rate in display applications, and are of great importance for practical organic displays. They also serve as an important tool in studying the transport mechanisms in organic conductors. Here, the modulation characteristics of several conventional small-molecule OLED structures [consisting of ITO/PEDOT:PSS(50 nm)/TPD(50 nm)/Alq3(various)/LiF(1 nm)/Al(90 nm)] are measured and analyzed in terms of mobility in and thickness of the Alq3 layer. Their optical response was shown to be limited by electron transport across the Alq3. Extracted electron mobilities were about 2-4×10-6 cm2/V · s (consistent with that reported in the literature) and near-identical values for mobility were obtained from devices of different thicknesses, suggesting that this method measures mobility independent of interface trap charging. This novel technique is a complement to large signal time of flight or delay time measurements (which can include interface and trap charging during the measurement) and can serve as a flexible method to study transport in actual devices.

© 2006 IEEE

Citation
Haichuan Mu and David Klotzkin, "Measurement of Electron Mobility in Alq3 From Optical Modulation Measurements in Multilayer Organic Light-Emitting Diodes," J. Display Technol. 2, 341-346 (2006)
http://www.opticsinfobase.org/jdt/abstract.cfm?URI=jdt-2-4-341


Sort:  Journal  |  Reset

References

  1. J. Kido, H. Hayase, K. Hongawa, K. Nagai, K. Okuyama, "Bright red light-emitting organic electroluminescent devices having a europium complex as an emitter," Appl. Phys. Lett. 65, 2124-2126 (1994).
  2. C. Adachi, T. Tsutsui, S. Saito, "Organic electroluminescent device having a hole conductor as an emitting layer," Appl. Phys. Lett. 55, 1489-1491 (1989).
  3. M. Ikai, S. Tokito, Y. Sakamoto, T. Suzuki, Y. Taga, "Highly efficient phosphorescence from organic light-emitting devices with an exciton-block layer," Appl. Phys. Lett. 79, 156-158 (2001).
  4. C. Adachi, M. A. Baldo, M. E. Thompson, S. R. Forrest, "Nearly 100% internal phosphorescence efficiency in an organic light-emitting device," J. Appl. Phys. 90, 5048-5051 (2001).
  5. D. V. Khramtchenkov, H. Bassler, V. I. Arkhipov, "A model of electroluminescence in organic double-layer light-emitting diodes," J. Appl. Phys. 79, 9283-9290 (1996).
  6. H. Kajii, T. Tsukagawa, T. Taneda, K. Yoshino, M. Ozaki, A. Fujii, M. Hikita, S. Tomaru, S. Imamura, H. Takenaka, J. Kobayashi, F. Yamamoto, Y. Ohmori, "Transient properties of organic electroluminescent diode using 8-hydroxyquinoline aluminum doped with rubrene as an electro-optical conversion device for polymeric integrated devices," Jpn. J. Appl. Phys. 41, 12746-2748 (2002).
  7. D. Braun, D. Moses, C. Zhang, A. J. Heeger, "Nanosecond transient electroluminescence from polymer light-emitting diodes," Appl. Phys. Lett. 61, 3092-3094 (1992).
  8. S. Das, A. J. Pal, "Transient electroluminescence under double voltage pulse: charge accumulation in light-emitting devices based on alizarin violet," Appl. Phys. Lett. 76, 1770-1772 (2000).
  9. C. Hosokawa, H. Tokailin, H. Higashi, T. Kusumoto, "Transient behavior of organic thin film electroluminescence," Appl. Phys. Lett. 60, 1220-1222 (1992).
  10. V. R. Nikitenko, V. I. Arkhipov, Y.-H. Tak, J. Pommerehne, H. Bassler, H.-H. Horhold, "The overshoot effect in transient electroluminescence from organic bilayer light emitting diodes: experiment and theory," J. Appl. Phys. 81, 7514-7525 (1997).
  11. L. Hassine, H. Bouchriha, J. Roussel, J.-L. Fave, "Transient response of a bilayer organic light emitting diode: building-up of external and recombination currents," J. Appl. Phys. 91, 5170-5175 (2002).
  12. R. Nagarajan, M. Ishikawa, T. Fukushima, R. S. Geels, J. E. Bowers, "High speed quantum well lasers and carrier transport effects," IEEE J. Quantum Electron. 28, 1990-2008 (1992).
  13. S. Barth, P. Muller, H. Riel, P. F. Seidler, W. Rieb, H. Vestweber, H. Bassler, "Electron mobility in tris(8-hydroxy-quinoline)aluminum thin films determined via transient electroluminescence from single- and multilayer organic light-emitting diodes," J. Appl. Phys. 89, 3711-3719 (2001).
  14. W. Brutting, H. Riel, T. Beierlein, W. Riess, "Influence of trapped and interfacial charges in organic multilayer light-emitting devices," J. Appl. Phys. 89, 1704-1712 (2001).
  15. J. Wang, R. G. Sun, G. Yu, A. J. Heeger, "Fast pulsed electroluminescence from polymer light-emitting diodes," J. Appl. Phys. 91, 2417-2422 (2002).
  16. M. Ichikawa, J. Amagai, Y. Horiba, T. Koyama, Y. Taniguchi, "Dynamic turn-on behavior of organic light-emitting devices with different work function cathode metals under fast pulse excitation," J. Appl. Phys. 94, 7796-7800 (2003).
  17. H. C. F. Martens, W. F. Pasveer, H. B. Brom, J. N. Huiberts, P. W. M. Blom, "Crossover from space-charge-limited to recombination-limited transport in polymer light-emitting diodes," Phys. Rev. B 63, 125328-1-125328-7 (2001).
  18. D. M. Pai, "Transient photoconductivity in Poly(N-vinylcarbazole)," J. Chem. Phys. 52, 2285-2291 (1970).
  19. M. Hiramoto, K. Koyama, K. Nakayama, M. Yokoyama, "Direct measurement of internal potential distribution in organic electroluminescent diodes during operation," Appl. Phys. Lett. 76, 1336-1338 (2000).
  20. E. Tutis, D. Berner, L. Zuppiroli, "Internal electric field and charge distribution in multilayer organic light-emitting diodes," J. Appl. Phys. 93, 4594-4602 (2003).
  21. S. C. Tse, H. H. Fong, S. K. So, "Electron transit time and reliable mobility measurements from thick film hydroxyquinoline-based organic light-emitting diode," J. Appl. Phys. 94, 2033-2037 (2004).
  22. S. P. Singh, V. L. Gupta, "Effect of electric field and temperature on hole mobility in ${\hbox{Alq}}_{3}$ material," Electron. Lett. 39, 862-863 (2003).
  23. H. H. P. Gommans, M. Kemerink, G. G. Andersson, R. M. T. Pijper, "Charge transport and trapping in Cs-doped poly(dialkoyx-p-phenylene vinylene)," Phys. Rev. B 69, 155216-1-155216-10 (2004).
  24. H. C. F. Martens, H. B. Brom, P. W. M. Blom, "Frequency-dependent electrical response of holes in poly(p-phenylene vinylene)," Phys. Rev. B 60, R8489-R8492 (1999).
  25. D. Poplavskyy, F. So, "Bipolar carrier transport in a conjugated polymer by complex admittance spectroscopy," J. Appl. Phys. 99, 33707-1 -33707-9 (2006).
  26. H. C. F. Martens, J. N. Huiberts, P. W. M. Blom, "Simultaneous measurement of electron and hole mobilities in polymer light-emitting diodes," Appl. Phys. Lett. 77, 1852-1854 (2000).

Cited By

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited