Green OLED’s: Electroluminescence and the electrical carrier transport


Organic Light Emitting Diodes (OLED) based on metal chelate complexes (Alq3) as the emmiting layer has been prepareded and studied in order to characterise their optical and electrical properties. Electrical measurements have been performed in order to establish the nature of carrier transport. The results point to a trap charge-limited conduction (TCL) with characteristic trap energy near 0.13 eV. In electroluminescence a large green band with a maximum at 2.4 eV was found as a result of three overlapping bands that are correlated with the organic layers. The origin of this luminescence spectrum was analysed.

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Pereira, L., Pontes, R. & Lopes, P. Green OLED’s: Electroluminescence and the electrical carrier transport. MRS Online Proceedings Library 771, 431 (2003).

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