We report the results of the morphological, electrical and optical characterisation of double-layer Alq3-based organic emitting diodes with a lithium fluoride (LiF)/Al cathode. A detailed electron microscopy investigation of their cross-section shows the presence of LiF isolated grains underneath the Al film. Due to the introduction of the LiF layer, luminance was larger than 30,000cd/m2at a bias voltage VB=25V with a maximum external luminous efficiency as large as 46lm/W at VB=20V. Performing on/off VBcycles at a very low frequency, each time a recovery of the initial electric and luminous performance was observed. The non-exponential decay of both electric current and luminance during each on-cycle has been interpreted as the signature of dispersive transport controlled by multiple trapping on localised states in an amorphous system. © 2004 Elsevier B.V. All rights reserved.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Materials Chemistry
- Polymers and Plastics
Montereali, R. M., Gambino, S., Loreti, S., Gagliardi, S., Pace, A., Baldacchini, G., & Michelotti, F. (2004). Morphological, electrical and optical properties of organic light-emitting diodes with a LiF/Al cathode and an Al-hydroxyquinoline/diamine junction. Synthetic Metals, 143(2), 171 - 174. https://doi.org/10.1016/j.synthmet.2003.11.008