ELECTROLUMINESCENCE FROM LIGHT-EMITTING-DIODES FABRICATED FROM CONDUCTING POLYMERS

Diodes with excellent current-voltage characteristics can be fabricated using metals with low work function as contacts to thin films of p-type pi-polymers. Charge injection at the rectifying contact leads to radiative recombination and efficient electroluminescence, i.e. to polymer light-emitting diodes (LEDs). Even at this very early stage of development, the polymer LEDs show special promise. They have low turn-on voltages (approximately 3 V), they have relatively high quantum efficiency (1% photons out per electron in), they exhibit different colors (both green and orange have been fabricated using different polymers), and they have been fabricated on both rigid (glass) and flexible (Mylar) substrates.