Nature 347, 539 - 541 (11 October 1990); doi:10.1038/347539a0

Light-emitting diodes based on conjugated polymers

J. H. Burroughes^*‡, D. D. C. Bradley^*, A. R. Brown^*, R. N. Marks^*, K. Mackay^*, R. H. Friend^*, P. L. Burns^† & A. B. Holmes^†

^*Cavendish Laboratory, Madingley Road, Cambridge CBS OHE, UK
^†University Chemistry Laboratory, Lensfield Road, Cambridge CB2 1EW, UK
^‡Present address: IBM Thomas J. Watson Research Centre, Yorktown Heights, New York 10598, USA.

CONJUGATED polymers are organic semiconductors, the semiconducting behaviour being associated with the molecular orbitals delocalized along the polymer chain. Their main advantage over non-polymeric organic semiconductors is the possibility of processing the polymer to form useful and robust structures. The response of the system to electronic excitation is nonlinear—the injection of an electron and a hole on the conjugated chain can lead to a self-localized excited state which can then decay radiatively, suggesting the possibility of using these materials in electroluminescent devices. We demonstrate here that poly(p-phenylene vinylene), prepared by way of a solution-processable precursor, can be used as the active element in a large-area light-emitting diode. The combination of good structural properties of this polymer, its ease of fabrication, and light emission in the green–yellow part of the spectrum with reasonably high efficiency, suggest that the polymer can be used for the development of large-area light-emitting displays.

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