Hostname: page-component-78c5997874-s2hrs Total loading time: 0 Render date: 2024-11-19T06:44:20.906Z Has data issue: false hasContentIssue false
  • English
  • Français

UV Photoemission Study of Interfaces Related to Organic EL Devices

Published online by Cambridge University Press:  10 February 2011

Kiyoshi Sugiyama ,
Kazuhiko Seki ,
Eisuke Ito ,
Yukio Ouchi  and
Hisao ISHII
Kiyoshi Sugiyama
Affiliation:
Department of Chemistry, Graduate School of Science, Nagoya University, Furocho, Chikusa-ku, Nagoya 464-01, JAPAN, [email protected]
Kazuhiko Seki
Affiliation:
Department of Chemistry, Graduate School of Science, Nagoya University, Furocho, Chikusa-ku, Nagoya 464-01, JAPAN, [email protected]
Eisuke Ito
Affiliation:
Department of Chemistry, Graduate School of Science, Nagoya University, Furocho, Chikusa-ku, Nagoya 464-01, JAPAN, [email protected]
Yukio Ouchi
Affiliation:
Department of Chemistry, Graduate School of Science, Nagoya University, Furocho, Chikusa-ku, Nagoya 464-01, JAPAN, [email protected]
Hisao ISHII
Affiliation:
Department of Chemistry, Graduate School of Science, Nagoya University, Furocho, Chikusa-ku, Nagoya 464-01, JAPAN, [email protected]
Get access

Abstract

Interfacial electronic structures related to organic electroluminescent (EL) devices were studied by UV photoemission spectroscopy (UPS). The two classes of interfaces studied were: (1) interfaces in a typical multilayer device AI/AIq3TPD/ITO, where Alq3 is tris(8-hydroxyquinolino)- aluminum, TPD is N,N×-diphenyl-NN×-(3-methylphenyl)- 1, 1‘-biphenyl-4,4’-diamine, and ITO is indium tin oxide, and (2) TTN/metals and TCNQ/metals interfaces, where TTN is tetrathianaphthacene and TCNQ is tetracyanoquinodimethane. The UPS studies of the specimen formed by the successive deposition of TPD, Alq3, and Al on ITO revealed interfacial energy diagrams, with the vacuum level shift of - 0.25 eV (downward) and - 0.1 eV (downward) at the TPD / ITO and the Alq3 / TPD interfaces, respectively. The deposition of TTN and TCNQ on metals showed opposite direction of the shift of the vacuum level, with the positive and negative charge at the vacuum side. This can be explained by considering the chargetransfer between the metal and the organic molecule, with these directions being consistent with the electron donating and accepting ability of these molecules.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 488: Symposium J – Electrical, Optical & Magnetic Properties of Organic IV , 1997 , 719
Copyright
Copyright © Materials Research Society 1998

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

[1] For example, Greenham, N.C. and Friend, R. H., Solid State Phys., 49, 1 (1995).Google Scholar
[2] For a review about UPS, e.g. Photoemission in Solids, vols. 1 and 2, edited by Cardona, M. and Ley, L., (Springer, 1978, 1979).Google Scholar
[3] Narioka, S., Ishii, H., Yoshimura, D., Sei, M., Ouchi, Y., Seki, K., Hasegawa, S., Miyazaki, T., Harima, Y., and Yamashita, K., Appl. Phys. Lett., 67, 1899 (1995).Google Scholar
[4] Seki, K., Tani, T., and Ishii, H., Thin Solid Films, 273, 20 (1996).Google Scholar
[5] Sugiyama, K., Yoshimura, D., Ito, E., Miyazaki, T., Hamatani, Y., Kawamoto, I., Ouchi, Y., and Seki, K., Mol. Cryst. Liq. Cryst., 286, 561 (1996).Google Scholar
[6] Yoshimra, D., Ishii, H., Narioka, S., Sei, M., Miyazaki, T., Ouchi, Y., Hasegawa, S., Harima, Y., Yamashita, K., and Seki, K., J. Electron Spectrosc., 78, 359 (1996).Google Scholar
[7] Ishii, H., Hasegawa, S., Yoshimura, D., Sugiyama, K., Narioka, S., Sei, M., Ouchi, Y., Seki, K., Harima, Y., and Yamashita, K., Mol. Cryst. Liq. Cryst., 296, 427 (1997).Google Scholar
[8] Yoshimura, D., Ishii, H., Narioka, S., Sei, M., Miyazaki, T., Ouchi, Y., Hasegawa, S., Harima, Y., Yamashita, K., and Seki, K., Synth. Metals, 86, 2399 (1997).Google Scholar
[9] Sugiyama, K., Yoshimura, D., Ito, E., Miyazaki, T., Hamatani, Y., Kawamoto, I.,. Ishi, , Ouchi, Y., and Seki, K., Synth. Metals, 86, 2425 (1997).Google Scholar
[10] Ishii, H. and Seki, K., IEEE Trans. Electron Devices, 44, 1295 (1997).Google Scholar
[11] Seki, K., Ito, E., and Ishii, H., Syn. Metals, in press.Google Scholar
[12] Ishii, H., Sugiyama, K., Yoshimura, D., Ito, E., Ouchi, Y., and Seki, K., IEEE J. Selected Topics Quant. Electronics., in press.Google Scholar
[13] Seki, K. and Ishii, H., J. Electron Spectrosc., in press.Google Scholar
[14] Park, Y., Choong, V., Ettedgui, E., Gao, Y., Hsieh, B. R., Wehrmeister, T., and Muellen, K., Appl. Phys. Lett., 69, 1080 (1996).Google Scholar
[15] Hirose, Y., Kahn, A., Aristov, V., Soukiassian, P., Appl. Phys. Lett., 68, 217 (1996).Google Scholar
[16] Salaneck, W. R., Stafstroem, S., and Bredas, J. -L., Conjugated Polymer Surfaces and Interfaces (Cambridge Univ. Press, 1996).Google Scholar
[17] Eden, R.C., Rev. Sci. Instrum., 41, 252 (1970).Google Scholar