Display device

1. A display device comprising:

a substrate having an active area and a non-active area;

a thin film transistor arranged on the active area of the substrate;

at least two planarization layers arranged on the thin film transistor;

signal links arranged on the non-active area of the substrate;

a first outer cover layer overlapping upper and side surfaces of the signal links in the non-active area;

conductive pads connected to the signal links;

a light emitting element connected to the thin film transistor; and

at least one dam arranged between the conductive pads and the light emitting element in the non-active area,

wherein the at least two planarization layers comprise:

a first planarization layer arranged on a protective film covering the thin film transistor in the active area, and

a second planarization layer arranged on the first planarization layer in the active area,

wherein the first outer cover layer is formed of a same material as the first planarization layer arranged on the protective film in the non-active area, and

the first outer cover layer is arranged between the at least one dam arranged on the protective film and the conductive pads in the non-active area.

2. The display device according to claim 1 , wherein the first outer cover layer is spaced apart from the at least two planarization layers.

3. The display device according to claim 1 , further comprising a pixel connection electrode connected to a drain electrode of the thin film transistor and arranged between the first and second planarization layers.

4. The display device according to claim 3 , wherein the pixel connection electrode is formed of a material which is a same material as the drain electrode.

5. The display device according to claim 3 , wherein

the signal links comprise:

a lower link formed of a same material as a gate electrode of the thin film transistor and coplanar with the gate electrode; and

an upper link formed of a same material as a source electrode and the drain electrode of the thin film transistor, the upper link being coplanar with the source electrode and the drain electrode and connected to the lower link,

wherein the first outer cover layer is formed of the same material as the first planarization layer and arranged on the protective film, and

wherein the protective film is arranged on the upper link.

6. The display device according to claim 5 , further comprising at least one link contact hole in an interlayer insulating film arranged between the source and drain electrodes and the gate electrode, the link contact hole exposing the lower link, wherein

the upper link is connected to the lower link through the at least one link contact hole, and

the first outer cover layer overlaps the at least one link contact hole.

7. The display device according to claim 3 , further comprising:

an encapsulation unit arranged on the light emitting element; and

a second outer cover layer arranged between the at least one dam and the conductive pads,

wherein the second outer cover layer is formed of a same material as the pixel connection electrode in the non-active area.

8. The display device according to claim 7 , wherein the encapsulation unit comprises an organic encapsulation layer, a first inorganic encapsulation layer, and a second inorganic encapsulation layer, wherein the first and the second inorganic encapsulation layers are formed of an inorganic insulating material.

9. The display device according to claim 7 , wherein the second outer cover layer is formed on the signal links to have a greater line width than that of the signal links.

10. The display device according to claim 7 , wherein:

the signal links are formed of a same material as a source electrode and the drain electrode of the thin film transistor; and

the second outer cover layer is formed of a same material as the pixel connection electrode so as to be in a same layer as the pixel connection electrode.

11. The display device according to claim 7 , further comprising a third outer cover layer formed on the second outer cover layer to have a greater line width than that of the second outer cover layer,

wherein the third outer cover layer is formed of a same material as the second planarization layer.

12. The display device according to claim 1 , further comprising: high voltage supply lines including first and second high voltage supply lines connected through line contact holes passing through the protective film and the first planarization layer.

13. The display device according to claim 12 , further comprising a pixel connection electrode arranged between the first and second planarization layers, and wherein the first high voltage supply line is formed of a same material as source and drain electrodes of the thin film transistor so as to be coplanar with the source and drain electrodes, and the second high voltage supply line is formed of a same material as the pixel connection electrode so as to be coplanar with the pixel connection electrode.

14. The display device according to claim 1 , wherein the first outer cover layer includes a plurality of first outer cover layer portions corresponding to a plurality of signal links in the signal links respectively.

15. The display device according to claim 14 , wherein each of the plurality of first outer cover layer portions has a flat upper surface or a stepwise upper surface on the signal links.