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Light-Emitting Diodes Using Semiconducting Oligothiophenes

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Abstract

The light-emitting diodes (LEDs) using semiconducting oligothiophenes, dimethylquaterthiophene (DMQtT, tetramer), dimethylquinquethiophene (DMQqT, pentamer) and dimethylsexithiophene (DMSxT, hexamer), have been investigated. These oligomers were deposited on ITO-coated glass in ultra high vacuum and an aluminum electrode was subsequently vacuum-deposited on top of the oligomers. These structures have the diode configuration with Schottky barrier between the oligomers and aluminum.

The LED using DMSxT shows good rectifying feature with the rectifying ratio of 1500 at ±10V. Red-orange emission is clearly observed above 4V bias. In this LED, DMSxT acts not only as an emitting layer but also as a hole transport layer. We have also fabricated and studied alternate layered structures of DMSxT/DMQtT and DMSxT/DMQqT as the emitting layer. In these configurations, the carrier recombination can be modulated because both DMQtT and DMQqT have energy gaps wider than that of DMSxT. The quantum efficiencies (photons emitted per carriers injected) of the LEDs using DMSxT/DMQtT and DMSxT/DMQqT are about one hundred times and one thousand times larger than that of the LED solely based on DMSxT, respectively. These results indicate that the layered structures are advantageous in increasing quantum efficiency of the emission.

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References

  1. C. W. Tang and S. A. VanSlyke, Appl. Phys. Lett. 59, 913 (1987).

    Article  Google Scholar 

  2. C. W. Tang, S. A. VanSlyke, and C. H. Chen, J. Appl. Phys. 65, 3610 (1989).

    Article  CAS  Google Scholar 

  3. C. Adachi, T. Tsutsui, and S. Saito, Appl. Phys. Lett. 55, 1489 (1989).

    Article  CAS  Google Scholar 

  4. J. H. Burroughes, D. D. C. Bradley, A. R. Brown, R. N. Marks, K. Mackay, R. H. Friend, P. L. Burns, and A. B. Holmes, Nature 347, 539 (1990).

    Article  CAS  Google Scholar 

  5. D. Braun and A. J. Heeger, Appl. Phys. Lett. 58, 1982 (1991).

    Article  CAS  Google Scholar 

  6. Y. Ohmori, M. Uchida, K. Muro, and K. Yoshino, Jpn. J. Appl. Phys. 30, L1938 (1991).

    Article  Google Scholar 

  7. T. Yamamoto, H. Wakayama, T. Fukuda, and T. Kanbara, J. Phys. Chem. 96, 8677 (1992).

    Article  CAS  Google Scholar 

  8. K. Uchiyama, H. Akimichi, S. Hotta, H. Noge, and H. Sakaki, to be published.

  9. G. Horowitz, D. Fichou, X. Peng, Z. Xu, and F. Garnier, Solid State Commun. 72, 381 (1989).

    Article  CAS  Google Scholar 

  10. F. Garnier, G. Horowitz, X. Peng, and D. Fichou, Adv. Mater. 2, 592 (1990).

    Article  CAS  Google Scholar 

  11. H. Akimichi, K. Waragai, S. Hotta, H. Kano, and H. Sakaki, Appl. Phys. Lett. 58, 1500 (1991).

    Article  CAS  Google Scholar 

  12. K. Waragai, H. Akimichi, S. Hotta, H. Kano, and H. Sakaki, Synth. Met. 57, 4053 (1993).

    Article  CAS  Google Scholar 

  13. S. Hotta and K. Waragai, J. Phys. Chem. 97, 7427 (1993).

    Article  CAS  Google Scholar 

  14. S. Hotta and K. Waragai, J. Mater. Chem. 1, 835 (1991).

    Article  CAS  Google Scholar 

  15. K. Waragai and S. Hotta, Synth. Met. 41, 519 (1991).

    Article  CAS  Google Scholar 

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Acknowledgments

We would like to thank Professor M. Gonokami for the valuable discussions and suggestions. This work is supported by Research Development Corporation of Japan (JRDC) through the Exploratory Research for Advanced Technology (ERATO) funding for Quantum Wave Project.

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Authors and Affiliations

  1. Quantum Wave Project, ERATO, Research Development Corporation of Japan, 3-10-1 Higashimita, Tama-ku, Kawasaki, 214, Japan

    K. Uchiyama, H. Akimichi, S. Hotta, H. Noge & H. Sakaki

  2. Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153, Japan

    H. Sakaki

Authors
  1. K. Uchiyama
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  2. H. Akimichi
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  3. S. Hotta
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  4. H. Noge
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  5. H. Sakaki
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Uchiyama, K., Akimichi, H., Hotta, S. et al. Light-Emitting Diodes Using Semiconducting Oligothiophenes. MRS Online Proceedings Library 328, 389–393 (1993). https://doi.org/10.1557/PROC-328-389

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  • DOI: https://doi.org/10.1557/PROC-328-389

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