In the light-emitting element 82R illustrated in FIG. 15(a), the first electrode 22 is positioned above the light-emitting layer 24c of the first wavelength range. The second electrode 25 is positioned below the light-emitting layer 24c of the first wavelength range. A portion of at least the upper face of the oxide layer 74a′ in contact with the oxide layer 74b is polycrystalline. That is, the upper face of the oxide layer 74a′ contains grains. The grains contained in the upper face of the oxide layer 74a′ increase an area of an interface between the upper face of the oxide layer 74a′ and the oxide layer 74b. Such a feature makes it possible to form electric dipoles more efficiently. Hence, in the light-emitting element 82R, the electrons can be injected efficiently.
In the light-emitting element 82R illustrated in FIG. 15(b), the first electrode 22 is positioned above the light-emitting layer 24c of the first wavelength range. The second electrode 25 is positioned below the light-emitting layer 24c of the first wavelength range. A portion of at least the upper face of the oxide layer 74a′ in contact with the oxide layer 74b′ is polycrystalline. The oxide layer 74b′ is made of an amorphous oxide. That is, the upper face of the oxide layer 74a′ contains grains.
