Light-emitting element with a pixel electrode having an uneven structure
A light-emitting element includes a pixel electrode arranged on an inorganic insulating film having an uneven structure on a first surface, and having a first electrode and a second electrode having an uneven structure finer than the uneven structure on a third surface, an electron injection layer arranged on the second electrode, an electron transport layer arranged on the electron injection layer, a light-emitting layer arranged on the electron transport layer and a common electrode arranged on the light-emitting layer.
1 . A light-emitting element comprising:
an inorganic insulating film having a first surface, the first surface has an uneven structure;
a pixel electrode arranged on the inorganic insulating film;
an electron injection layer arranged on the pixel electrode;
an electron transport layer arranged on the electron injection layer;
a light-emitting layer arranged on the electron transport layer; and
a common electrode arranged on the light-emitting layer,
wherein
the pixel electrode includes a first electrode having a second surface, and a second electrode having a third surface,
the first electrode is in contact with the first surface,
the second electrode is in contact with the second surface, and
the third surface has an uneven structure finer than the uneven structure of the first surface.
2 . The light-emitting element according to claim 1 , wherein
the pixel electrode is a cathode, and
the common electrode is an anode.
3 . The light-emitting element according to claim 1 , wherein
the first electrode contains a first metal oxide, and
the second electrode contains a second metal oxide different from the first metal oxide.
4 . The light-emitting element according to claim 3 , wherein
a lattice constant of the second metal oxide is smaller than a lattice constant of the first metal oxide.
5 . The light-emitting element according to claim 3 , wherein
the first metal oxide is ITO, and
the second metal oxide is ZnO or MoO.
6 . The light-emitting element according to claim 1 , wherein
a thickness of the second electrode is thinner than a thickness of the first electrode, and
a thickness of the electron injection layer is thinner than the thickness of the first electrode.
7 . The light-emitting element according to claim 1 , wherein
the uneven structure of the first surface has convex parts, and
a distance between one of the convex parts and another one of the convex parts adjacent to the one of the convex parts is 5 μm or less.
8 . A display device including the light-emitting element according to claim 1 , comprising:
a display unit including a plurality of the light-emitting elements; and
a control circuit electrically connected to the plurality of the light-emitting elements and controlling the plurality of the light-emitting elements.
9 . The display device according to claim 8 , wherein
the pixel electrode is a cathode, and
the common electrode is an anode.
10 . The display device according to claim 8 , wherein
the first electrode contains a first metal oxide, and
the second electrode contains a second metal oxide different from the first metal oxide.
11 . The display device according to claim 10 , wherein
a lattice constant of the second metal oxide is smaller than a lattice constant of the first metal oxide.
12 . The display device according to claim 10 , wherein
the first metal oxide is ITO, and
the second metal oxide is ZnO or MoO.
13 . The display device according to claim 8 , wherein
a thickness of the second electrode is thinner than a thickness of the first electrode, and
a thickness of the electron injection layer is thinner than the thickness of the first electrode.
14 . The display device according to claim 8 , wherein
the uneven structure of the first surface has convex parts, and
a distance between one of the convex parts and another one of the convex parts adjacent to the one of the convex parts is 5 μm or less.