Hostname: page-component-78c5997874-dh8gc Total loading time: 0 Render date: 2024-11-15T02:26:04.501Z Has data issue: false hasContentIssue false
  • English
  • Français

Conjugated Polymer Surfaces and Interfaces for Light-Emitting Devices

Published online by Cambridge University Press:  29 November 2013

W.R. Salaneck  and
J.L. Brédas
Get access

Extract

Since the discovery of high electrical conductivity in doped polyacetylene in 1977, π-conjugated polymers have emerged as viable semiconducting electronic materials for numerous applications. In the context of polymer electronic devices, one must understand the nature of the polymer surface's electronic structure and the interface with metals. For conjugated polymers, photoelectron spectroscopy—especially in connection with quantum-chemical modeling—provides a maximum amount of both chemical and electronic structural information in one (type of) measurement. Some details of the early stages of interface formation with metals on the surfaces of conjugated polymers and model molecular solids in connection with polymer-based light-emitting devices (LEDs) are outlined. Then a chosen set of issues is summarized in a band structure diagram for a polymer LED, based upon a “clean calcium electrode” on the clean surface of a thin film of poly(p-phenylene vinylene) (PPV). This diagram helps to point out the complexity of the systems involved in polymer LEDs. No such thing as “an ideal metal-on-polymer contact” exists. There is always some chemistry occurring at the interface.

Type
Polymeric and Organic Electronic Materials and Applications
Information
MRS Bulletin , Volume 22 , Issue 6 , June 1997 , pp. 46 - 51
Copyright
Copyright © Materials Research Society 1997

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.Brédas, J.L. and Silbey, R., Conjugated Polymers (Kluwer Academic Publishers, Dordrecht, 1991).CrossRefGoogle ScholarPubMed
2.Salaneck, W.R., Lundström, I., and B. Rånby, , in Proc. 81st Nobel Symp. in Chemistry: Conjugated Polymers and Related Materials; The Interconnection of Chemical and Electronic Structure (Oxford University Press, Oxford, 1993).Google Scholar
3.Skotheim, T., Reynolds, J.R., and Elsenbaumer, R.L., Handbook of Conducting Polymers-II (Marcel Dekker, Inc., New York, 1997).Google Scholar
4.Burroughes, J.H., Bradley, D.D.C., Brown, A.R., Marks, R.N., Mackay, K., Friend, R.H., Burn, P.L., and Holmes, A.B., Nature 347 (1990) p. 539.CrossRefGoogle Scholar
5.Friend, R.H., in Nobel Symposium in Chemistry: Conjugated Polymers and Related Materials; The Interconnection of Chemical and Electronic Structure, edited by Salaneck, W.R., Lundström, I., and Rånby, B. (Oxford University Press, Oxford, 1993) p. 285.Google Scholar
6.Braun, D. and Heeger, A.J., Appl. Phys. Lett. 58 (1991) p. 1982.CrossRefGoogle Scholar
7.Burn, P.L., Holmes, A.B., Kraft, A., Bradley, D.D.C., Brown, A.R., and Friend, R.H., J. Chem. Soc., Chem. Commun. (1992) p. 32.Google Scholar
8.Burn, P.L., Kraft, A., Bradley, D.D.C., Brown, A.R., Friend, R.H., Gymer, R.W., and Jackson, R.W., J. Am. Chem. Soc. 115 (1993) p. 10117.CrossRefGoogle Scholar
9.Gill, R.E., Malliaras, G.G., Wildeman, J., and Hadziioannou, G., Adv. Mater. 6 (1994) p. 132.CrossRefGoogle Scholar
10.Grem, G., Leditzky, G., Ultrich, B., and Leising, G., Adv. Mater. 4 (1992) p. 36.CrossRefGoogle Scholar
11.Gustavsson, G., Cao, Y., Treacy, G.M., Klavetter, F., Colaneri, N., and Heeger, A.J., Nature 357 (1992) p. 477.CrossRefGoogle Scholar
12.Halliday, D.A., Burn, P.L., Bradley, D.D.C., Friend, R.H., Gelsen, O.M., Holmes, A.B., Kraft, A., Martens, J.H.F., and Pichler, K., Adv. Mater. 5 (1993) p. 40.CrossRefGoogle Scholar
13.Ohmori, Y., Uchida, M., Muro, K., and Yoshino, K., Jpn. J. Appl. Phys. 30 (1991) p. L1938.CrossRefGoogle Scholar
14.Ohmori, Y., Uchida, M., Muro, K., and Yoshino, K., Solid State Commun. 80 (1991) p. 605.CrossRefGoogle Scholar
15.Parker, I.D., J. Appl. Phys. 75 (1994) p. 1656.CrossRefGoogle Scholar
16.Greenham, N.C., Moratti, S.C., Bradley, D.D.C., Friend, R.H., and Holmes, A.B., Nature 365 (1993) p. 628.CrossRefGoogle Scholar
17.Salaneck, W.R., Stafström, S., and Brédas, J.L., Conjugated Polymer Surfaces and Interfaces (Cambridge University Press, Cambridge, 1996).CrossRefGoogle Scholar
18.Lögdlund, M., Dannetun, P., and Salaneck, W.R., “Electronic and Chemical Structure of Polymer Surfaces and Interfaces as studied by Photoelectron Spectroscopy,” in Handbook of Conducting Polymers-II, edited by Skotheim, T., Reynolds, J.R., and Elsenbaumer, R.L. (Marcel Dekker, Inc., New York, 1997).Google Scholar
19.Fahlman, M., Beljonne, D., Lögdlund, M., Burn, P.L., Holmes, A.B., Friend, R.H., Brédas, J.L., and Salaneck, W.R., Chem. Phys. Lett. 214 (1993) p. 327.CrossRefGoogle Scholar
20.Dannetun, P., private communication.Google Scholar
21.Fahlman, M., Rasmusson, J., Kaeriyama, K., Clark, D.T., Beamson, G., and Salaneck, W.R., Synth. Met. 66 (1994) p. 123.CrossRefGoogle Scholar
22.Fahlman, M., Moratti, S., Holmes, A.B., Salaneck, W.R., and Bredas, J.L., Chem. Eur. J. in press.Google Scholar
23.Salaneck, W.R., Inganäs, O., Thémans, B., Nilsson, J.O., Sjögren, B., Österholm, J-E., Bredas, J-L., and Svensson, S., J. Chem. Phys. 89 (1988) p. 4613.CrossRefGoogle Scholar
24.Lögdlund, M., Lazzaroni, R., Stafström, S., Salaneck, W.R., and Brédas, J.L., Phys. Rev. Lett. 63 (1989) p. 1841.CrossRefGoogle Scholar
25.Lazzaroni, R., Lögdlund, M., Stafström, S., Salaneck, W.R., and Brédas, J.L., J. Chem. Phys. 93 (1990) p. 6.CrossRefGoogle Scholar
26.Lazzaroni, R., Lögdlund, M., Stafström, S., Salaneck, W.R., Bradley, D.D.C., Friend, R.H., Sato, N., Orti, E., and Brédas, J.L., “Electronic Structure of Processable Conducting Polymers,” Conjugated Polymeric Materials Opportunities in Electronics: Optoelectronics, and Molecular Electronics, edited by Brédas, J.L. and Chance, R. (NATO ASI Series E, vol. 182, Kluwer Academic, Dordrecht, 1990) p. 149.CrossRefGoogle Scholar
27.Lazzaroni, R., Lögdlund, M., Calderone, A., Brédas, J.L., Dannetun, P., Fauquet, C., Fredriksson, C., Stafström, S., and Salaneck, W.R., Synth. Met. 71 (1995) p. 2159.CrossRefGoogle Scholar
28.Spangler, C.W., Nickel, E.G., and Hall, T.J., Am. Chem. Soc., Div. Polym. Chem. 28 (1987) p. 219.Google Scholar
29.Lögdlund, M., Dannetun, P., Sjögren, B., Boman, M., Fredriksson, C., Stafström, S., and Salaneck, W.R., Synth. Met. 51 (1992) p. 187.CrossRefGoogle Scholar
30.Lögdlund, M., Dannetun, P., Stafström, S., Salaneck, W.R., Ramsey, M.G., Spangler, C.W., Fredriksson, C., and Brédas, J.L., Phys. Rev. Lett. 70 (1993) p. 970.CrossRefGoogle Scholar
31.Dannetun, P., Boman, M., Stafström, S., Salaneck, W.R., Lazzaroni, R., Fredriksson, C., Brédas, J.L., Zamboni, R., and Taliani, C., J. Chem. Phys. 99 (1993) p. 664.CrossRefGoogle Scholar
32.Salaneck, W.R. and Brédas, J.L., Adv. Mater. 8 (1996) p. 48.CrossRefGoogle Scholar
33.André, J.M., Dekhalle, J., and Brédas, J.L., Quantum Chemistry Aided Design of Organic Polymers (World Scientific, Singapore, 1991).CrossRefGoogle Scholar
34.Brédas, J.L., Chance, R.R., Silbey, R., Nicolas, G., and Durand, P., J. Chem. Phys. 75 (1981) p. 255.CrossRefGoogle Scholar
35.Brédas, J.L. and Salaneck, W.R., “Characterization of the Interfaces between Low Work Function Metals and Conjugated Polymers in Light Emitting Diodes,” Organic Electroluminescence, edited by Bradley, D.D.C. and Tsutsui, T. (Cambridge University Press, Cambridge) in press.Google Scholar
36.Fredriksson, C. and Brédas, J.L., J. Chem. Phys. 98 (1993) p. 4253.CrossRefGoogle Scholar
37.Dannetun, P., Lögdlund, M., Fredriksson, C., Lazzaroni, R., Fauquet, C., Stafström, S., Spangler, C.W., Brédas, J.L., and Salaneck, W.R., J. Chem. Phys. 100 (1994) p. 6765.CrossRefGoogle Scholar
38.Dannetun, P., Fahlman, M., Fauquet, C., Kaerijama, K., Sonoda, Y., Lazzaroni, R., Bredas, J.L., and Salaneck, W.R., “Interface Formation Between Poly(2,5-diheptyl-p-phenylenevinylene) and Calcium: Implications for Light Emitting diodes,” Organic Materials for Electronics: Conjugated Polymer Interfaces with Metals and Semiconductors,” edited by Brédas, J.L., Salaneck, W.R., and Wegner, G. (North Holland, Amsterdam, 1994) p. 113.Google Scholar
39.Ettedgui, E., Razafitrimo, H., Gao, Y., and Hsieh, B.R., Synth. Met. 78 (1996) p. 247.CrossRefGoogle Scholar
40.Gao, Y., Park, K.T., and Hsieh, B.R., J. Chem. Phys. 97 (1992) p. 6991.CrossRefGoogle Scholar
41.Schott, M., “Undoped (Semiconducting) Conjugated Polymers,” Organic Conductors: Fundamentals and Applications, edited by Farges, J.P. (Marcel Dekker, Inc., New York, 1994) p. 539.Google Scholar
42.Salaneck, W.R., “Intermolecular Relaxation Energies in the Ultraviolet Photoelectron Spectroscopy of Molecular Solids: Molecular-Ion States in Aromatic Pendant Group Polyrhers,” Characterization of Molecular Structure of Polymers by Photon, Electron and Ion Probes,” edited by Fabish, T.J., Dwight, D., and Thomas, H.R. (Am. Chem. Soc., Washington, DC, 1981) p. 121.CrossRefGoogle Scholar
43.Greenham, N.C. and Friend, R.H., Solid State Phys. 49 (1996) p. 1.CrossRefGoogle Scholar
44.Hsieh, B.R., Ettedgui, E., Park, K.T., and Gao, Y., Mol. Cryst. Liq. Cryst. 256 (1994) p. 71.CrossRefGoogle Scholar
45.Park, Y., Ettedgui, E., Choong, V., Gao, Y., Hsieh, B.R., Wehrmeister, T., and Mullen, K., Appl. Phys. Lett. 69 (1996) p. 1080.CrossRefGoogle Scholar
46.Bröms, P., Birgersson, J., Johnsson, N., Lögdlund, M., and Salaneck, W.R., Synth. Met. 74 (1995) p. 179.CrossRefGoogle Scholar
47.Lobatch, A., Rubin, I.R., and Sobolev, A.B., Status Solidi B 161 (1990) p. 271.CrossRefGoogle Scholar
48.Kirm, M., Feldbach, E., Kink, R., Lushchik, A., Lushchik, C., Maaroos, A., and Martinson, I., J. Elec. Spec. Rel. Phenom. 79 (1996) p. 91.CrossRefGoogle Scholar