Display device and manufacturing method therefor

1. A display device comprising:

a substrate comprising a display area and a non-display area; and

a plurality of pixels on the display area, each of the plurality of pixels comprising a plurality of sub-pixels,

wherein each sub-pixel of the plurality of sub-pixels comprises an emission area and a non-emission area: a pixel circuit layer comprising at least one transistor; and a display element layer comprising at least one light emitting element connected to the at least one transistor to emit light,

wherein the display element layer further comprises:

a first electrode and a second electrode spaced apart from each other with the at least one light emitting element therebetween;

the at least one light emitting element disposed between the first electrode and the second electrode in a plan view; and

a planarization layer on the pixel circuit layer, and in direct contact with at least a portion of each of opposite ends of the at least one light emitting element,

wherein the planarization layer overlaps with each of the first electrode and the second electrode in a plan view.

2. The display device according to claim 1 , wherein a width of the planarization layer is equal to or greater than a length of the light emitting element.

3. The display device according to claim 2 , wherein the display element layer further comprises:

a first insulating layer to enclose a portion of each of the first electrode and the second electrode; and

a support layer on the first insulating layer, to support the at least one light emitting element.

4. The display device according to claim 3 , wherein the support layer is to be inserted between a lower surface of the at least one light emitting element and the first insulating layer on a surface of the pixel circuit layer that faces the lower surface of the at least one light emitting element.

5. The display device according to claim 4 , wherein the planarization layer and the support layer are integrally provided, and comprise an identical material.

6. The display device according to claim 5 , wherein the planarization layer and the support layer each comprise an organic insulating layer including an organic material.

7. The display device according to claim 3 , wherein the display element layer further comprises:

a second insulating layer on an upper surface of the at least one light emitting element;

a first contact electrode to connect any one end of the opposite ends of the at least one light emitting element with the first electrode; and

a second contact electrode to connect a remaining end of the opposite ends of the at least one light emitting element with the second electrode.

8. The display device according to claim 7 , wherein the first contact electrode and the second contact electrode are on an identical layer, and are spaced apart from each other on the second insulating layer and electrically separated from each other.

9. The display device according to claim 7 , wherein each of the first contact electrode and the second contact electrode is on the planarization layer and overlaps with the planarization layer.

10. The display device according to claim 9 , wherein the display element layer further comprises:

a third insulating layer on the first contact electrode; and

a fourth insulating layer on the second contact electrode.

11. The display device according to claim 10 , wherein the first contact electrode and the second contact electrode are on different layers and electrically separated from each other.

12. The display device according to claim 7 , wherein the display element layer further comprises a capping layer respectively between the first electrode and the first contact electrode and between the second electrode and the second contact electrode.

13. The display device according to claim 12 , wherein the first insulating layer exposes a portion of the capping layer on the first electrode so that the first electrode is electrically connected with the first contact electrode, and the first insulating layer exposes a portion of the capping layer on the second electrode so that the second electrode is electrically connected with the second contact electrode.

14. The display device according to claim 13 , wherein the at least one light emitting element comprises a light emitting diode in a shape of a cylinder having a size of a micrometer scale or a nanometer scale.

15. A display device comprising:

a substrate comprising a display area and a non-display area; and

a plurality of pixels on the display area, each of the plurality of pixels comprising a plurality of sub-pixels,

wherein each sub-pixel of the plurality of sub-pixels comprises an emission area and a non-emission area: a pixel circuit layer comprising at least one transistor; and a display element layer comprising at least one light emitting element connected to the at least one transistor to emit light,

wherein the display element layer further comprises:

a first electrode and a second electrode spaced apart from each other with the at least one light emitting element therebetween;

the at least one light emitting element disposed between the first electrode and the second electrode in a plan view; and

a planarization layer on the pixel circuit layer, and in contact with at least a portion of each of opposite ends of the at least one light emitting element,

wherein the planarization layer overlaps with each of the first electrode and the second electrode in a plan view, and

wherein a height of the planarization layer is less than a diameter of the light emitting element, in a sectional view.

16. A method of fabricating a display device, the method comprising:

providing a substrate comprising a plurality of sub-pixels, each of the plurality of sub-pixels comprising an emission area and a non-emission area; and

forming, on the substrate, a display element layer to emit light from the emission area of each of the plurality of sub-pixels,

wherein the forming the display element layer comprises:

forming a first electrode and a second electrode spaced apart from each other in the emission area of each of the plurality of sub-pixels;

forming a first insulating material layer on the first electrode and the second electrode;

aligning a plurality of light emitting elements between the first electrode and the second electrode by respectively applying corresponding alignment voltages to the first electrode and the second electrode;

forming an insulating pattern for covering each of the plurality of light emitting element and a portion of the first insulating material layer by depositing a second insulating material layer on an overall surface of the substrate and then patterning the second insulating material layer;

forming, by removing a portion of the insulating pattern through an ashing process, a planarization layer on the first insulating material layer, the planarization layer overlapping the plurality of light emitting elements;

forming a second insulating layer for covering a portion of an upper surface of the plurality of light emitting elements; and

forming a first contact electrode and a second contact electrode on the substrate including the second insulating layer.

17. The method according to claim 16 , further comprising, before the forming the first contact electrode and the second contact electrode, forming a first insulating layer by removing a portion of the first insulating material layer corresponding to the first electrode to expose the first electrode, and removing a portion of the first insulating material layer corresponding to the second electrode to expose the second electrode.

18. The method according to claim 17 , wherein the planarization layer overlaps with each of the first electrode, the second electrode, and the plurality of light emitting elements, in a plan view.

19. The method according to claim 18 , wherein the forming the planarization layer comprises forming a support layer to be inserted between a lower surface of the plurality of light emitting elements and the first insulating material layer.

20. The method according to claim 19 , wherein the planarization layer and the support layer each comprise an organic insulating layer including an organic material.