Display device and method for fabricating the same
A display device includes: a plurality of pixel electrodes disposed to be spaced apart from each other on a substrate; a plurality of light emitting elements disposed on the plurality of pixel electrodes; a first undoped semiconductor layer on the plurality of light emitting elements; a second undoped semiconductor layer between the first undoped semiconductor layer and the plurality of light emitting elements; and a common electrode layer between the first undoped semiconductor layer and the second undoped semiconductor layer, wherein the common electrode layer includes at least two parts which are separated from each other.
1 . A display device comprising:
a plurality of pixel electrodes spaced apart from each other on a substrate;
a plurality of light emitting elements disposed on the plurality of pixel electrodes;
a first undoped semiconductor layer on the plurality of light emitting elements;
a second undoped semiconductor layer between the first undoped semiconductor layer and the plurality of light emitting elements; and
a common electrode layer between the first undoped semiconductor layer and the second undoped semiconductor layer,
wherein the common electrode layer includes at least two parts which are separated from each other,
wherein the plurality of light emitting elements include:
a first light emitting element;
a second light emitting element; and
a third light emitting element,
wherein the common electrode layer includes:
a first common electrode part on the first light emitting element; and
a second common electrode part on the second light emitting element and the third light emitting element, and
wherein the first common electrode part and the second common electrode part are spaced apart from each other, and
wherein the second common electrode part on the second light emitting element and the second common electrode part on the third light emitting element are integral with each other.
2 . The display device of claim 1 , wherein
the second undoped semiconductor layer includes:
a first undoped semiconductor part on the first light emitting element; and
a second undoped semiconductor part on the second light emitting element and the third light emitting element, and
the first undoped semiconductor part and the second undoped semiconductor part are spaced apart from each other.
3 . The display device of claim 2 , wherein the second undoped semiconductor part on the second light emitting element and the second undoped semiconductor part on the third light emitting element are integral with each other.
4 . The display device of claim 3 , wherein the first undoped semiconductor layer on the first light emitting element, the second light emitting element, and the third light emitting element are integral with each other.
5 . The display device of claim 1 , wherein the first common electrode part includes a porous semiconductor layer.
6 . The display device of claim 5 , wherein the porous semiconductor layer includes porous gallium nitride (GaN).
7 . The display device of claim 5 , wherein a porous density of the first common electrode part is greater than a porous density of the second common electrode part.
8 . A method for fabrication of the display device of claim 1 , the method comprising:
forming the first undoped semiconductor layer on the substrate;
forming the common electrode layer including an n-type semiconductor on the first undoped semiconductor layer;
forming the second undoped semiconductor layer on the common electrode layer;
forming a first light emitting element of the plurality of light emitting elements on the second undoped semiconductor layer;
forming a second light emitting element of the plurality of light emitting elements on the second undoped semiconductor layer;
forming a first common electrode part of the common electrode layer in an area for forming a third light emitting element of the plurality of light emitting elements and a second common electrode part of the common electrode layer on the first and second light emitting elements by selectively removing the second undoped semiconductor layer and the common electrode layer;
forming the first common electrode part in a porous structure; and
forming the third light emitting element on the second undoped semiconductor layer.
9 . The method of claim 8 , wherein the forming of the first common electrode part in the porous structure is performed by an electro-chemical (EC) etching process.
10 . The method of claim 8 , wherein
the first common electrode part includes a porous semiconductor layer, and
the porous semiconductor layer includes porous gallium nitride (GaN).
11 . The method of claim 10 , wherein a porous density of the first common electrode part is greater than a porous density of the second common electrode part.
12 . The method of claim 8 , wherein
the first light emitting element includes a blue light emitting element,
the second light emitting element includes a green light emitting element, and
the third light emitting element includes a red light emitting element.