It is an object of the present invention to provide a light emitting
element with a low driving voltage. In a light emitting element, a first
electrode; and a first composite layer, a second composite layer, a light
emitting layer, an electron transporting layer, an electron injecting
layer, and a second electrode, which are stacked over the first
electrode, are included. The first composite layer and the second
composite layer each include metal oxide and an organic compound. A
concentration of metal oxide in the first composite layer is higher than
a concentration of metal oxide in the second composite layer, whereby a
light emitting element with a low driving voltage can be obtained.
Further, the composite layer is not limited to a two-layer structure. A
multi-layer structure can be employed. However, a concentration of metal
oxide in the composite layer is gradually higher from the light emitting
layer to first electrode side.