| abstract |
The present invention is directed to simplified OLED structures comprising an anode layer (611), a hole injecting layer (HIL) (612) in direct contact with an anode layer, an emissive organic electron transporting layer (ETL) (613) in direct contact with the hole injecting layer, and a cathode layer (614) in direct contact with the emissive organic electron transporting layer. The hole injecting material used in the hole injection layer is characterized, in particular, as being an organic material having an ionization potential that is not more than about 0.7 eV greater than the ionization potential of the material used for the anode. |