LONG LIFETIME PHOSPHORESCENT ORGANIC LIGHT EMITTING DEVICE (OLED) STRUCTURES

摘要

An organic light emitting device is provided having an emissive layer with an internal interface. The concentration of a second phosphorescent material in a second organic layer is different from the concentration of a first phosphorescent material in a first organic layer, creating the interface. The materials in the first and second organic layers may be the same or different. In addition to this interface within the emissive layer, the device has one or more features designed to mitigate failure mechanisms which may be associated with electrons or excitons passing from the cathode through the emissive layer to damage organic layers on the anode side of the emissive layer. In addition, devices are provided having an interface within the emissive layer as described above, and a lower energy emissive material on at least one side of the interface.