Display device including metal compound layer surrounding wiring layer stack for reducing light reflectance

1. A display device comprising:

a substrate; and

a wiring layer disposed on the substrate, the wiring layer including a conductive metal layer and a metal compound layer of the conductive metal layer,

wherein the metal compound layer surrounds the conductive metal layer;

wherein the wiring layer includes a first conductive metal layer, a second conductive metal layer, a third conductive metal layer, and a first metal compound layer which are sequentially disposed on the substrate,

wherein the first conductive metal layer and the third conductive metal layer include a first metal, the second conductive metal layer includes a second metal different from the first metal, and the first metal compound layer includes the second metal,

wherein the first metal compound layer covers a top surface of the third conductive metal layer, and

wherein the first metal is titanium (Ti), the second metal is copper (Cu), and the first metal compound is at least one of copper oxide (CuOx) or copper nitride (CuNx).

2. The display device of claim 1 , wherein the first metal compound layer has a light reflectance lower than that of the first conductive metal layer, the second conductive metal layer, and the third conductive metal layer.

3. The display device of claim 1 , further comprising:

a second metal compound layer surrounding a side surface of the first conductive metal layer and having a light reflectance lower than that of the first conductive metal layer, the second metal compound layer including a metal included in the first conductive metal layer;

a third metal compound layer surrounding a side surface of the second conductive metal layer and having a light reflectance lower than that of the second conductive metal layer, the third metal compound layer including a metal included in the second conductive metal layer; and

a fourth metal compound layer surrounding a side surface of the third conductive metal layer and having a light reflectance lower than that of the third conductive metal layer, the fourth metal compound layer including a metal included in the third conductive metal layer.

4. The display device of claim 3 , wherein side surfaces of the first metal compound layer, the second metal compound layer, the third metal compound layer, and the fourth metal compound layer are aligned with each other.

5. The display device of claim 4 , wherein side surfaces of the first conductive metal layer, the second conductive metal layer, and the third conductive metal layer are aligned with each other.

6. The display device of claim 3 , wherein the second metal compound layer and the fourth metal compound layer include at least one of titanium oxide (TiOx) or titanium nitride (TiNx), and the third metal compound layer includes at least one of copper oxide (CuOx) or copper nitride (CuNx).

7. The display device of claim 1 , wherein the first metal compound layer has an uneven surface.

8. The display device of claim 1 , wherein the wiring layer is a gate line or a data line.

9. The display device of claim 8 , further comprising an insulating layer disposed on the wiring layer and including a contact hole, and a pixel electrode disposed on the insulating layer,

wherein the first metal layer exposes at least a part of the third conductive metal layer, and the pixel electrode is in contact with the third conductive metal layer exposed by the contact hole.

10. A display device comprising:

a substrate;

a first wiring layer disposed on the substrate and including a gate signal wiring;

a first insulating layer disposed on the first wiring layer;

a second wiring layer disposed on the first insulating layer and including a data signal wiring, a data pad connected to the data signal wiring, and a drain electrode spaced apart from the data signal wiring;

a second insulating layer disposed on the second wiring layer; and

a pixel electrode disposed on the second insulating layer and electrically connected to the drain electrode,

wherein the second wiring layer includes a first conductive metal layer and a metal compound layer which includes an oxide or a nitride of the first conductive metal layer and is disposed on the first conductive metal layer,

wherein the metal compound layer has a reflectance lower than that of the first conductive metal layer, and

wherein the metal compound layer has a resistance higher than that of the first area conductive metal layer;

wherein the first conductive metal layer includes a first conductive metal layer, a second conductive metal layer, and a third conductive metal layer which are sequentially disposed on the substrate, and

wherein the metal compound layer includes a first metal compound layer covering a side surface of the first conductive metal layer, a second metal compound layer covering a side surface of the second conductive metal layer, a third metal compound layer covering a side surface of the third conductive metal layer, and a fourth metal compound layer covering a top surface of the third conductive metal layer.

11. The display device of claim 10 , wherein the data signal wiring includes the metal compound layer covering a top surface of the first conductive metal layer, the data pad includes the metal compound layer completely exposing a top surface of the first conductive metal layer, and the drain electrode includes the metal compound layer partially exposing a top surface of the first conductive metal layer.

12. The display device of claim 11 , wherein the pixel electrode is in contact with the top surface of the first conductive metal layer partially exposed by a contact hole disposed in the metal compound layer.

13. The display device of claim 3 , wherein the first conductive metal layer and the third conductive metal layer include titanium (Ti), and the second conductive metal layer includes copper (Cu), and

wherein the first metal oxide layer and the third metal oxide layer include at least one of titanium nitride (TiNx) or titanium oxide (TiOx), and the second metal oxide layer and the fourth metal oxide layer include at least one of copper nitride (CuNx) or copper oxide (CuOx).