High performance organic polymer light-emitting heterostructure devices

We report a high performance electroluminescence device based on bi-layer c onjugated polymer structures consisting of a hole transporting (amine-fluor ene) and an emissive (benzothiadiazole-fluorene) polymer layers prepared by the spin-coating technique on the glass substrate. Devices showed green em ission with an electroluminescence peak located at around 545 nm and a full width at half maximum of about 80 nm. Our devices have also shown a high b rightness (similar to 10 000 cd/m(2) at 0.84 mA/mm(2)), good emission effic iency (similar to 14.5 cd/A) and luminous efficiency (2.26 lm/W), a large e xternal quantum efficiency (3.8%), and a reasonable forward-to-reverse bias current rectification ratio (>10(3) at +/-25 V). (C) 1999 American Institu te of Physics. [S0003-6951(99)04316-8].