Wire structure, method for fabricating wire, thin film transistor substrate, and method for fabricating thin film transistor substrate

1. A method for fabricating a wire, the method comprising:

forming a barrier layer including copper nitride on a substrate;

forming a copper conductive layer including copper or a copper alloy on the barrier layer;

forming a capping layer including molybdenum or a molybdenum alloy on the copper conductive layer; and

etching the capping layer, the copper conductive layer, and the barrier layer to form a pattern, wherein a concentration of copper nitride in the barrier layer is greater near the substrate than near the copper conductive layer.

2. The method of claim 1 , wherein the forming of the barrier layer comprises performing sputtering with a target of copper or a copper alloy in an atmosphere including nitrogen.

3. The method of claim 2 , wherein the forming of the copper conductive layer is performed in-situ subsequently to the forming of the barrier layer in an atmosphere of nitrogen.

4. The method of claim 1 , wherein the thickness of the barrier layer is in a range of less than 100 Å.

5. The method of claim 1 , wherein the barrier layer includes nitrogen in an amount of 0.001-50 atomic percent.

6. The method of claim 1 , wherein the substrate is an insulating substrate, a semiconductor layer, an insulating layer, or glass.

7. The method of claim 1 , wherein the etching of the capping layer, the copper conductive layer, and the barrier layer is performed in a batch process.

8. The method of claim 1 , wherein the etching of the capping layer, the copper conductive layer, and the barrier layer is performed using a same etchant.

9. The method of claim 1 , wherein as a concentration of nitrogen in the barrier layer is increased, a thickness of the barrier layer may be made smaller.