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Electrically Detected Magnetic Resonance of MEH-PPV diodes

Published online by Cambridge University Press:  01 February 2011

George B. Silva ,
Lucas F. Santos ,
Roberto M. Faria  and
Carlos F. O. Graeff
George B. Silva
Affiliation:
Departamento de Física e Matemática-FFCLRP-USP, Av. Bandeirantes 3900, 14040-901 Ribeirão Preto, Brazil
Lucas F. Santos
Affiliation:
Instituto de Física de São Carlos-USP, C.P. 369, 13560-970 São Carlos, Brazil
Roberto M. Faria
Affiliation:
Instituto de Física de São Carlos-USP, C.P. 369, 13560-970 São Carlos, Brazil
Carlos F. O. Graeff
Affiliation:
Departamento de Física e Matemática-FFCLRP-USP, Av. Bandeirantes 3900, 14040-901 Ribeirão Preto, Brazil
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Abstract

In this work electrically detected magnetic resonance (EDMR) is used to study the electronic properties of poly(2-methoxy-5-(2'-ethyl-hexoxy)-1,4-phenylene vinylene) (MEHPPV) diodes. Two kinds of MEH-PPV diodes were characterized. The first one was a bipolar light emitting diode whose structure was ITO/MEH-PPV/Al. In this diode the EDMR signal is composed of two lines, a line that can be fitted by a lorentzian with peak-to-peak linewidth of 5.0 ± 0.5 G and the other best fitted with gaussian line with a linewidth of 24 ± 1 G. The g factor of both components is 2.002 ± 0.001 and signals were only observed at forward bias. The second diode is a hole only device, with a structure ITO/MEH-PPV/Au, the EDMR signal in this case is dominated by a gaussian line with peak-to-peak linewidth of 5 ± 1 G and average g factor of 2.0014 ± 0.0002. In high forward bias (V > 30 volts at T = 130K) a second line could be observed with a linewidth of 10 ± 2 G and a g factor of 2.0012 ± 0.0004. The signal from both types of diodes is quenching, and tipically10-5 in amplitude. The EDMR signal is assigned to the spin-dependent fusion of two like-charged polarons. Our results indicate that the narrower component is coming from positive polarons while the broader to negative polarons.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 725: Symposium P – Organic and Polymeric Materials and Devices-Optical, Electrical, and Optoelectronic Properties , 2002 , P4.18
Copyright
Copyright © Materials Research Society 2002

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References

[1] Heeger, A.J. Solid State Comun. 107, 673 (1998).Google Scholar
[2] Heeger, A.J. in Conjugated Polymers: The Interconnection of Chemical and Electronic Structure, Proceedings of the Nobel Symposium (Ed. Salaneck, W.R. Lundström, I. and Ranby, B.), Oxford University Press, Oxford, (1993).Google Scholar
[3] Solomon, I. Biegelsen, D. Knights, J. C. Solid State Comun. 22 (1977) 505.Google Scholar
[4] Dersch, H. Schweitzer, L. Knights, J. C. Phys. Rev. B 28, 4678 (1983).Google Scholar
[5] Stich, B. Greulich-Weber, S., and Spaeth, J.M. J. Appl. Phys. 77, 1546 (1995).Google Scholar
[6] Graeff, C. F. O. Brunello, C. A. J Non-Cryst Solids 273, 289 (2000)Google Scholar
[7] Graeff, C.F.O. Brunello, C.A. Faria, R.M. Synthetic Met. 101, 805 (1999)Google Scholar
[8] Swanson, A.R. Shinar, J. Brown, A.R. Bradley, D.D.C. Friend, R. H. Burn, P.L. Kraft, A. and Holmes, B. Phys. Rev. B 46, 15072 (1992).Google Scholar
[9] Lepine, D.J. Phys. Rev. B 6, 463 (1972).Google Scholar
[10] Silva, G.B. Santos, L.F. Faria, R.M. Graeff, C.F.O, Physica B 308-310, 1078 (2001).Google Scholar
[11] Wudl, F. Srdanov, G. US Patent No. 5, 189, 136, 1993.Google Scholar
[12] Cumpston, H. and Jensen, K.F. J. Appl. Pol. Science 69, 2451 (1998).Google Scholar
[13] Kuroda, S. Ohnishi, T. and Nogushi, T. Phys. Rev. Lett. 72, 286 (1994).Google Scholar
[14] Shinar, J. in: Handbook of organic Conductive Molecules and Polymers: vol 3, ed. Nalwa, H.S. (John Wiley & Sons, New York, 1997).Google Scholar
[15] Blom, P.W.M. Jong, M.J.M. de, Vleggaar, J.J.M. Appl. Phys. Lett. 68, 3308 (1996).Google Scholar