Light-emitting element and light-emitting device
摘要
說明書
The amorphous oxide contained in the oxide layer 74b′ can provide excellent coverage on the oxide layer 74a′ having grains. Such a feature facilitates formation of the electric dipoles 1. Moreover, the amorphous oxide of the oxide layer 74b′ allows the oxide layer 74b′ to have greater uniformity in film thickness. Such a feature makes it possible to transport the electrons more uniformly in the oxide layer 74b′. 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 83R, the electrons can be injected efficiently.
Note that, in this embodiment, a laser beam is used to thermally treat a portion including the upper face of the oxide layer 74a′ in order to polycrystallize the upper face of the oxide layer 74a′. However, the technique of the polycrystallization shall not be limited to such a technique. The technique to polycrystallize the oxide layer 74a′ and the kind of a polycrystalline oxide contained in the oxide layer 74a′ shall not be limited to a particular technique and a particular kind, as long as the density of the oxygen atoms in the oxide layer (the ETL) 74a′ is lower than the density of the oxygen atoms in the oxide layer 74b, or the density of the oxygen atoms in the oxide layer 74b′.
