LIGHT-EMITTING ELEMENT, LIGHT-EMITTING DEVICE, DISPLAY, AND ELECTRONIC DEVICE

摘要

In the light-emitting element in which a plurality of EL layers is separated from each other by a charge generation layer, provided are an electron relay layer in contact with an anode side of the charge generation region and an electron transport layer in contact with the electron relay layer. The electron transport layer contains an alkaline earth metal. A concentration gradient of the alkaline earth metal contained in the electron transport layer is such that the concentration of the alkaline earth metal becomes lower from an interface between the electron transport layer and the electron relay layer to the anode.