Display device

1. A display device, comprising:

a substrate;

a driving circuit disposed on the substrate;

a first conductive layer disposed on the driving circuit;

at least one of light emitting units disposed on the first conductive layer and electrically connected to the driving circuit; and

a second conductive layer disposed on at least one of the light emitting units;

wherein the second conductive layer has a first surface corresponding to at least one of the light emitting units and a second surface corresponding to a region outside of the first conductive layer; and

wherein a roughness of the first surface is greater than a roughness of at least a part of the second surface.

2. The display device according to claim 1 , wherein the roughness of the first surface is greater than or equal to 3 nm and less than or equal to 100 nm.

3. The display device according to claim 1 , wherein the first conductive layer has a top surface and a bottom surface, the top surface is opposite to the bottom surface and neighbors at least one of the light emitting units, and a roughness of the top surface is greater than a roughness of at least the part of the second surface.

4. The display device according to claim 1 , wherein each of the light emitting units comprises:

a first electrode disposed on the first conductive layer;

a first semiconductor layer disposed on the first electrode;

a second semiconductor layer disposed on the first semiconductor layer; and

a second electrode disposed on the second semiconductor layer.

5. The display device according to claim 4 ,

wherein the first electrode has a third surface adjacent to the first conductive layer and the second electrode has a fourth surface adjacent to the second conductive layer; and

wherein a roughness of the fourth surface is greater than a roughness of the third surface.

6. The display device according to claim 4 ,

wherein the first semiconductor layer has a fifth surface adjacent to the first electrode and the second semiconductor layer has a sixth surface adjacent to the second electrode; and

wherein a roughness of the sixth surface is greater than a roughness of the fifth surface.

7. The display device according to claim 1 , further comprising a first scattering layer disposed on the light emitting units.

8. The display device according to claim 1 , further comprising a second scattering layer disposed on the first conductive layer.

9. The display device according to claim 8 , wherein the second scattering layer includes scattering particles.

10. A display device, comprising:

a substrate;

a driving circuit disposed on the substrate;

a first conductive layer disposed on the driving circuit; and

at least one of light emitting units disposed on the first conductive layer and electrically connected to the driving circuit, wherein each of the light emitting units comprises a first semiconductor layer disposed on the first conductive layer and a second semiconductor layer disposed on the first semiconductor layer;

wherein the first semiconductor layer has a first surface adjacent to the first conductive layer and the second semiconductor layer has a second surface farthest from the first conductive layer; and

wherein a roughness of the second surface is greater than a roughness of the first surface.

11. The display device according to claim 10 ,

wherein each of the light emitting units further comprises a first electrode disposed between the first conductive layer and the first semiconductor layer and a second electrode disposed on the second semiconductor layer;

wherein the first electrode has a third surface adjacent to the first conductive layer, and the second electrode has a fourth surface farthest from the first conductive layer; and

wherein a roughness of the fourth surface is greater than a roughness of the third surface.

12. The display device according to claim 10 , wherein the first conductive layer has a top surface and a bottom surface, the top surface is opposite to the bottom surface and neighbors at least one of the light emitting units, and a roughness of the top surface is greater than a roughness of the first surface.

13. The display device according to claim 10 , further comprising a second conductive layer and a first scattering layer successively disposed on the light emitting units.

14. The display device according to claim 10 , further comprising a second scattering layer disposed on the first conductive layer.

15. The display device according to claim 14 , wherein the second scattering layer includes scattering particles.

16. A display device, comprising:

a substrate;

a driving circuit disposed on the substrate;

a first conductive layer disposed on the driving circuit; and

at least one of light emitting units disposed on the first conductive layer and electrically connected to the driving circuit, wherein each of the light emitting units comprises a first electrode disposed on the first conductive layer, a first semiconductor layer disposed on the first electrode, a second semiconductor layer disposed on the first semiconductor layer, and a second electrode disposed on the second semiconductor layer;

wherein the first electrode has a first surface adjacent to the first conductive layer and the second electrode has a second surface farthest from the first conductive layer; and

wherein a roughness of the second surface is greater than a roughness of the first surface.

17. The display device according to claim 16 , wherein the first conductive layer has a top surface and a bottom surface, the top surface is opposite to the bottom surface and neighbors at least one of the light emitting units, and a roughness of the top surface is greater than a roughness of the first surface.

18. The display device according to claim 16 , further comprising a second conductive layer and a first scattering layer successively disposed on the light emitting units.

19. The display device according to claim 16 , further comprising a second scattering layer disposed on the first conductive layer.

20. The display device according to claim 19 , wherein the second scattering layer includes scattering particles.