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Approaches to Advanced Organic Light Emitting Diodes: Materials and Devices

Published online by Cambridge University Press:  21 March 2011

Masamichi Ikai  and
Yasunori Taga
Masamichi Ikai
Affiliation:
TOYOTA Central Research & Development Laboratories, Inc., Nagakute, Aichi 480-1192, Japan
Yasunori Taga
Affiliation:
TOYOTA Central Research & Development Laboratories, Inc., Nagakute, Aichi 480-1192, Japan
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Abstract

We present our recent findings on the development of organic light emitting diodes (OLEDs). One of the keys to highly efficient phosphorescent emission in organic light-emitting diodes is to confine triplet excitons generated within the emitting layer. To confine triplet excitons, we employ perfluorinated phenylene dendrimers (C60F42) as a both hole- and exciton-block layer, and a hole-transport material (4,4',4”-tris(N-carbazolyl) triphenylamine [TCTA]) as a host for the phosphorescent dopant, Ir(ppy)3, in the emitting layer. The maximum external quantum efficiency reaches to 19.2%, and is over 15% even at high injection current densities of 10 to 20 mA/cm2, where the brightness of the device reaches to approximately 10,000 cd/m2.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 665: Symposium C – Electronic, Optical and Optoelectronic Polymers and Oligomers , 2001 , C4.3
Copyright
Copyright © Materials Research Society 2001

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References

REFERENCES

1. Baldo, M.A., O'Brien, D.F., You, Y., Shoustikov, A., Sibley, S., Thompson, M.E., and Forrest, S.R., Nature 395, 151 (1998).Google Scholar
2. Adachi, C., Baldo, M.A., Forrest, S.R., and Thompson, M.E., Appl. Phys. Lett. 77, 904 (2000).Google Scholar
3. O'Brien, D.F., Baldo, M.A., Thompson, M.E., and Forrest, S.R., Appl. Phys. Lett. 74, 442 (1999).Google Scholar
4. Baldo, M.A., Lamansky, S., Burrows, P.E., Thompson, M.E., and Forrest, S.R., Appl. Phys. Lett. 75, 4 (1999).Google Scholar
5. Baldo, M.A., Thompson, M.E., and Forrest, S.R., Nature 403, 750 (2000).Google Scholar
6. Tsutsui, T. and Saito, S., in Intrinsically Conducting Polymers: An Emerging Technology, edited by Aldissi, M. (Kluwer Academic, Dordrecht, 1993), Vol. 246, p. 123.Google Scholar
7. Rothberg, L.J. and Lovinger, A.J., J. Mater. Res. 11, 3174 (1996).Google Scholar
8. Yang, M.-J., and Tsutsui, T., Proceedings of the 10th International Workshop on Inorganic and Organic Electroluminescence, December 4-7 (2000), Hamamatsu, Japan, p.227–230.Google Scholar
9. Fukase, A., and Kido, J., Proceedings of the 10th International Workshop on Inorganic and Organic Electroluminescence, December 4-7 (2000), Hamamatsu, Japan, p.293–295.Google Scholar
10. Baldo, M.A., Adachi, C., and Forrest, S.R., Phys. Rev. B. 62, 10967 (2000).Google Scholar
11. Stolka, M., Yanus, J.F., and Pai, D.M., J. Phys. Chem. 88, 4707 (1984).Google Scholar
12. Kuwabara, Y., Ogawa, H., Inada, H., Noma, N., and Shirota, Y., Adv. Mater. 6, 677 (1994).Google Scholar
13. Sakamoto, Y., Suzuki, T., Miura, A., Fujikawa, H., Tokito, S., and Taga, Y., J. Am. Chem. Soc. 122, 1832 (2000).Google Scholar
14. (a)Chemistry of Organic Fluorine Compounds II: Critical Review; Hudlicky, M., Pavlath, A.E., Eds.; ACS Monograph 187; (American Chemical Society, Washington DC, 1995). (b) Organofluorine Chemistry: Principle and Commercial Applications; R.E. Banks, B.E. Smart, J.C. Tatlow, Eds.; (Topics in Applied Chemistry; Plenum Press: New York, 1994).Google Scholar
15. Tokito, S., Noda, K., Fujikawa, H. and Taga, Y., (unpublished)Google Scholar
16. Shiga, T., Tokito, S., and Taga, Y., Proceedings of the 10th International Workshop on Inorganic and Organic Electroluminescence, December 4-7 (2000), Hamamatsu, Japan, p.179–182.Google Scholar
17. Mori, T., Tokito, S., and Taga, Y.., (unpublished) (the HOMO and LUMO levels of Ir(ppy)3 are 5.2eV and 2.8eV, respectively.)Google Scholar
18. Cleave, V., Yahioglu, G., Barny, P.L., Hwang, D.-H., Holmes, A.B., Friend, R.H. and Tessler, N., Adv. Mater. 13, 44 (2001).Google Scholar