Concepedia

Abstract

The environment in which organic light-emitting diodes (OLEDs) are fabricated can profoundly affect device performance, as shown here. The previously reported asymmetric injection behavior of Mg:Ag/Alq3/Mg:Ag structures (where Alq3 is tris(8-hydroxyquinoline) aluminum) is investigated by fabricating and testing these structures under ultra-high vacuum with and without exposing the bottom electrode to oxygen and water vapor. It is demonstrated that devices fabricated under strict vacuum conditions exhibit symmetric I–V characteristics while those exposed to air do not.