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Hole injection and transport in a fluorene-containing copolymer

Published online by Cambridge University Press:  11 February 2011

Rizwan U. A. Khan ,
Theo Kreouzis ,
Dmytro Poplavskyy  and
Donal D. C. Bradley
Rizwan U. A. Khan
Affiliation:
Blackett Laboratory, Imperial College London, London SW7 2BW, U.K.
Theo Kreouzis
Affiliation:
Blackett Laboratory, Imperial College London, London SW7 2BW, U.K.
Dmytro Poplavskyy
Affiliation:
Blackett Laboratory, Imperial College London, London SW7 2BW, U.K.
Donal D. C. Bradley
Affiliation:
Blackett Laboratory, Imperial College London, London SW7 2BW, U.K.
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Abstract

We have studied the electrical properties of a fluorene-containing copolymer which is currently being developed for state-of-the-art blue polymer LEDs. This copolymer is made up of three functional groups which are nominally the hole-conducting, electron conducting and emissive regions. Using a combination of current/voltage, time-of-flight and dark injection transient versus temperature measurements, the injection and transport properties of the material have been investigated. Hole injection from polystyrene sulphonate doped polyethylenedioxythiophene (PEDOT:PSS) into the polymer is found to be consistent with an ohmic contact. Hole transport within the fluorene copolymer is found to possess a mobility that is two orders of magnitude lower than that for previously studied polymers containing the copolymer constituents. Using the equations for trap-free space-charge limited current, predicted J/V characteristics have been obtained from the mobility values derived using the time-of-flight technique. We discuss both the reduced hole mobility of the copolymer, and the discrepancies between the measured and predicted J/V characteristics, in terms of variations in both the trap and transport site densities and their energetic and spatial distributions.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 734: Symposia A/B – Defect-Mediated Phenomena in Ordered Polymers – Polymer/Metal Interfaces and Defect Mediated Phenomena in Ordered Polymers , 2002 , B6.3
Copyright
Copyright © Materials Research Society 2003

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References

REFERENCES

[1] Friend, R. H., Bradley, D. D. C., and Holmes, A. B., Phys. World 5, 42 (1992).CrossRefGoogle Scholar
[2] Burroughes, J. H. and Friend, R. H., Phys. World 1, 24 (1988).CrossRefGoogle Scholar
[3] Campbell, A. J., Bradley, D. D. C., Virgili, T., Lidzey, D. G., and Antoniadis, H., Appl. Phys. Lett. 79, 3872 (2001).CrossRefGoogle Scholar
[4] Blom, P. W. M., deJong, M. J. M., and Vleggaar, J. J. M., Appl. Phys. Lett. 68, 3308 (1996).CrossRefGoogle Scholar
[5] Campbell, A. J., Bradley, D. D. C., and Lidzey, D. G., J. Appl. Phys. 82, 6326 (1997).CrossRefGoogle Scholar
[6] Janietz, S., Bradley, D. D. C., Grell, M., Biebeler, C., Inbasekaran, M., and Woo, E. P., Appl. Phys. Lett. 73, 2453 (1998).CrossRefGoogle Scholar
[7] Redecker, M., Bradley, D. D. C., Inbasekaran, M., Wu, W. W., and Woo, E. P., Adv. Mat. 11, 241 (1999).3.0.CO;2-J>CrossRefGoogle Scholar
[8] Brown, T. M., Kim, J. S., Friend, R. H., Cacialli, F., Daik, R., and Feast, W. J., Appl. Phys. Lett. 75, 1679 (1999).CrossRefGoogle Scholar
[9] Campbell, A. J., Bradley, D. D. C., Antoniadis, H., Inbasekaran, M., Wu, W. W., and Woo, E. P., Appl. Phys. Lett. 76, 1734 (2000).CrossRefGoogle Scholar
[10] Abkowitz, M., Facci, J. S., and Stolka, M., Appl. Phys. Lett. 63, 1892 (1993).CrossRefGoogle Scholar
[11] Borsenberger, P. M., Pautmeier, L., and Bässler, H., J. Chem. Phys. 94, 5447 (1991).CrossRefGoogle Scholar
[12] Martens, H. C. F., Huiberts, J. N., and Blom, P. W. M., Appl. Phys. Lett. 77, 1852 (2000).CrossRefGoogle Scholar
[13] Borsenberger, P. M. and Bässler, H., J. Chem. Phys. 95, 5327 (1991).CrossRefGoogle Scholar
[14] Giebeler, C., Antoniadis, H., Bradley, D. D. C., and Shirota, Y., Appl. Phys. Lett. 72, 2448 (1998).CrossRefGoogle Scholar
[15] Poplavskyy, D. and Nelson, J., accepted for publication in J. Appl. Phys.Google Scholar
[16] Campbell, A. J., Bradley, D. D. C., and Antoniadis, H., J. Appl. Phys. 89, 3343 (2001).CrossRefGoogle Scholar