ABSTRACT
Acknowledgments .............................................................................................................. 580
References .......................................................................................................................... 580
The discovery of efficient electroluminescence in thin films of conjugated polymers in 1990
initiated a large international effort by academics, industries, and national laboratories to
understand and develop a new technology based on polymer light emitters. From the scientific
point of view, such a large effort opened new avenue for research in the area of charge transport
in disordered, highly correlated, and low-dimension materials, as well as in the novel synthesis
of semiconducting polymers and small-molecule organics with unprecedented purity. From the
technology point of view, such materials promised a complete paradigm shift in the manufac-
ture of semiconducting devices, enabling inexpensive liquid-based processing under atmos-
pheric conditions rather than expensive high-temperature and vacuum-based processing. This
promise motivated significant progress in polymer material development, purity, and stability,
and helped to revitalize the promise for two other related fields, namely organic photovoltaics
and transistors. Organic-based light-emitting devices are now competitive to many inorganic-
based devices in efficiency and stability. Nonetheless, the initial promise of inexpensive liquid-
based or print-based manufacturing has yet to be fully realized.
