Organic EL element

摘要

Provided is an organic EL element which withstands mass production of organic EL display panels, and promises driving at a low voltage and high luminous efficiency due to excellent hole-injection efficiency. Specifically, an organic EL element is formed by sequentially laminating an anode, a hole injection layer, a buffer layer, a light-emitting layer, and a cathode on one surface of a substrate. The hole injection layer is a at least 2 nm thick tungsten oxide layer formed under predetermined film forming conditions, and includes an occupied energy level that is 1.8 eV to 3.6 eV lower than a lowest energy level of a valence band of the hole injection layer in terms of a binding energy. This reduces the hole injection barrier between the anode and the hole injection layer and the hole injection barrier between the hole injection layer and the buffer layer.

主权项

1. An organic EL element, comprising:
an anode; a functional layer containing an organic material; and a hole injection layer for injecting holes to the functional layer, the hole injection layer being between the anode and the functional layer and in contact with the anode, wherein the hole injection layer comprises tungsten oxide, is at least 2 nm thick, and includes an occupied energy level that is 1.8 electron volts to 3.6 electron volts lower than a lowest energy level of a valence band of the hole injection layer in terms of a binding energy, and the occupied energy level at an interface between the hole injection layer and the anode is approximately equal to an energy level of a Fermi level of the anode in terms of the binding energy.