Temperature dependence of current transport and electroluminescence in vacuum deposited organic light emitting devices

Publication Type:

Journal Article

Source:

Jpn. J. Appl. Phys., IOP Publishing, Volume 35, Issue 3B, p.L401 (1996)

Keywords:

1996, 2013 and earlier

Abstract:

We measure the temperature dependence of the current-voltage (I-V) and electroluminescence (EL) characteristics of organic light emitting devices
based on the molecular compound; tris(8-hydroxyquinoline) aluminum (Alq3).
We find that the current is limited by a large density of traps with an
exponential energy distribution below the Alq3 lowest unoccupied molecular
orbital. The measured trap density suggests that each molecular site may
serve as an electron trap, and that EL arises from the recombination of
trapped charge. The relationship between the I-V characteristics and EL
provides insight into the optimization of vacuum deposited organic light
emitting devices.