Infra-red and visible electroluminescence from ErQ based OLEDs

Organic light emitting diodes have been fabricated using erbium tris(8-hydroxyquinoline) as the emitting layer and N,N′-diphenyl-N,N′-bis(3-methylphenyl)-1,1′-biphenyl-4,4′-diamine (TPD) as the hole transporting layer. Room temperature electroluminescence was observed both in the visible region and at 1.5 μm due to intra-atomic transitions between the 4I13/2 and 4I15/2 levels in the Er3+ ion. The electroluminescence of these devices was found to be dependent on the deposition conditions.