Abstract
Conduction in aluminum(III) 8-hydroxyquinoline (Alq3) was modeled based on trap-charge limited conduction of electrons in the bulk. The evolution of a narrow Gaussian distribution of localized trap states below the lowest unoccupied molecular orbital (LUMO) of Alq3, lying against a natural exponential background, was used to explain changes in the current-voltage characteristic and external quantum efficiency with time observed by many researchers for organic light-emitting diodes. Based on the change of the shape of the J-V curve, the depth of the electron trap states that were formed during aging was about 0.25 eV below the LUMO of Alq3. An increase in drive voltage and decrease in efficiency is predicted with aging by this model for current densities in a reasonable range, assuming that the evolved trap states are non-emissive and also non-quenching. The products of chemical aging can account for the generation of traps at the observed depth.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
