Display device and manufacturing method thereof
A display device includes pixels. Each of the pixels includes light emitting elements including a first end portion and a second end portion disposed in a length direction; an intermediate layer that exposes a portion of each of the light emitting elements and fixes each of the light emitting elements in the length direction; a pixel circuit layer including at least one transistor electrically connected to one of the first end portion and the second end portion of each of the light emitting elements; a first electrode disposed on the at least one transistor and electrically connected to the a least one transistor; and a second electrode electrically connected to the other of the first end portion and the second end portion of each of the light emitting elements. The first electrode and the second electrode include different materials and are disposed in different layers.
1 . A display device comprising:
pixels, wherein each of the pixels includes:
a base layer;
an encapsulation layer disposed on the base layer;
light emitting elements disposed between the base layer and the encapsulation layer, each of the light emitting elements including a first end portion and a second end portion disposed in a length direction;
an intermediate layer disposed between the base layer and the encapsulation layer and including a single groove that exposes a portion of each of the light emitting elements, the intermediate layer fixing each of the light emitting elements in the length direction;
a pixel circuit layer disposed between the intermediate layer and the encapsulation layer and including at least one transistor electrically connected to one of the first end portion and the second end portion of each of the light emitting elements;
a first electrode disposed between the pixel circuit layer and the light emitting elements, disposed between the at least one transistor and the encapsulation layer, and electrically connecting the one of the first end portion and the second end portion of each of the light emitting elements to the at least one transistor; and
a second electrode disposed between the base layer and the light emitting elements and electrically connected to the other of the first end portion and the second end portion of each of the light emitting elements, and
wherein the first electrode and the second electrode include different materials and are disposed in different layers.
2 . The display device of claim 1 , wherein
one of the first electrode and the second electrode includes a transparent conductive material, and
the other of the first electrode and the second electrode includes an opaque conductive material.
3 . The display device of claim 2 , wherein the intermediate layer includes a curable material.
4 . The display device of claim 3 , wherein
the pixel circuit layer is disposed on the light emitting elements and the intermediate layer,
the first electrode is disposed above the light emitting elements, and the second electrode is disposed below the light emitting elements,
the first electrode is disposed on the second electrode, and
the light emitting elements are disposed between the first electrode and the second electrode.
5 . The display device of claim 4 , wherein
the first electrode includes a transparent conductive material, and
the second electrode includes an opaque conductive material.
6 . The display device of claim 5 , wherein the second electrode reflects light emitted from the light emitting elements in an upper direction of the light emitting elements.
7 . The display device of claim 5 , wherein each of the light emitting elements includes:
a first semiconductor layer contacting the first electrode and electrically connected to the first electrode;
a second semiconductor layer contacting the second electrode and electrically connected to the second electrode; and
an active layer disposed between the first semiconductor layer and the second semiconductor layer, wherein
the first semiconductor layer is a p-type semiconductor layer doped with a p-type dopant, and
the second semiconductor layer is an n-type semiconductor layer doped with an n-type dopant.
8 . The display device of claim 7 , wherein
the first end portion of each of the light emitting elements is disposed at an upper end portion of a corresponding light emitting element along the length direction,
the second end portion of each of the light emitting elements is disposed at a lower end portion of the corresponding light emitting element along the length direction;
the first semiconductor layer is disposed at the first end portion of each of the light emitting elements, and
the second semiconductor layer is disposed at the second end portion of each of the light emitting elements.
9 . The display device of claim 8 , wherein
the pixel circuit layer includes at least one insulating layer,
the at least one insulating layer includes a first opening in which a portion is removed from an area overlapping the light emitting elements, and
the first electrode is disposed on the first end portion of each of the light emitting elements within the first opening of the at least one insulating layer.
10 . The display device of claim 9 , further comprising:
a conductive pattern disposed on at least a portion of the first electrode within the first opening of the at least one insulating layer,
wherein the conductive pattern does not overlap the light emitting elements in a cross-sectional view.
11 . The display device of claim 9 , further comprising:
a bank disposed between the second electrode and the pixel circuit layer, surrounding the light emitting elements, and including a second opening exposing a portion of the second electrode;
a first passivation layer overlapping the first electrode;
a second passivation layer disposed on the first passivation layer; and
a third passivation layer overlapping the second electrode,
wherein the intermediate layer fills the second opening of the bank, and
wherein the groove exposes the first end portion of each of the light emitting elements.
12 . The display device of claim 11 , wherein the first opening of the at least one insulating layer coincides with the second opening.
13 . The display device of claim 11 , wherein
the intermediate layer is disposed between the second electrode and the pixel circuit layer, and
the groove exposes the first end portion of each of the light emitting elements.
14 . The display device of claim 11 , wherein the pixel circuit layer is disposed between the bank and the encapsulation layer and includes a light blocking member overlapping the at least one transistor.
15 . The display device of claim 3 , further comprising:
a substrate on which the pixels are disposed, wherein
the pixel circuit layer is disposed between the substrate and the light emitting elements,
the first electrode is disposed below the light emitting elements,
the second electrode is disposed above the light emitting elements,
the second electrode is disposed on the first electrode, and
the light emitting elements are disposed between the first electrode and the second electrode.
16 . The display device of claim 15 , wherein
the first electrode includes an opaque conductive material,
the second electrode includes a transparent conductive material, and
the first electrode reflects light emitted from the light emitting elements in an upper direction of the light emitting elements.
17 . The display device of claim 16 , wherein
each of the light emitting elements includes:
a p-type semiconductor layer doped with a p-type dopant, the p-type semiconductor layer contacting the first electrode and electrically connected to the first electrode;
a n-type semiconductor layer doped with a n-type dopant, the n-type semiconductor layer contacting the second electrode and electrically connected to the second electrode; and
an active layer disposed between the p-type semiconductor layer and the n-type semiconductor layer,
the p-type semiconductor layer directly contacts the first electrode and/or the n-type semiconductor layer directly contacts the second electrode,
the first end portion of each of the light emitting elements is disposed at a lower end portion of a corresponding light emitting element along the length direction,
the second end portion of each of the light emitting elements is disposed at an upper end portion of the corresponding light emitting element along the length direction,
the p-type semiconductor layer is disposed at the first end portion of each of the light emitting elements, and
the n-type semiconductor layer is disposed at the second end portion of each of the light emitting elements.