Patent ID: 8946693
Filing Date: 2015-02-03
Classification: H01L,H05B

Abstract:
1. An organic EL element comprising: an anode; a cathode; banks; a functional layer between the anode and the cathode, the functional layer including one or more sublayers, the one or more sublayers including a light-emitting sublayer, the light-emitting sublayer defined by the banks and containing an organic material; and a hole injection layer between the anode and the functional layer, wherein the hole injection layer comprises tungsten oxide, an Ultraviolet Photoelectron Spectroscopy (UPS) spectrum, obtained from a UPS measurement, has a protrusion appearing near a Fermi surface and within a region corresponding to a binding energy range lower than a top of a valence band, the tungsten oxide contained in the hole injection layer satisfies a condition, determined from an X-ray Photoelectron Spectroscopy (XPS) measurement, that a ratio in a number density of atoms other than tungsten atoms and oxygen atoms to the tungsten atoms does not exceed approximately 0.83, the hole injection layer has a surface facing the functional layer and has a recessed structure such that a portion of the surface overlapping with the light-emitting sublayer is located closer to the anode than other portions of the surface overlapping with the banks, the portion of the surface overlapping with the light-emitting sublayer and the other portions of the surface overlapping with the banks are located closer to the anode than a peripheral bottom surface of each of the banks, and the recessed structure comprises an inner surface that is in contact with the functional layer, the inner surface including an inner bottom surface and an inner side surface that is continuous with the inner bottom surface.