Process for forming a redundant structure

1. A method of fabricating a device, comprising:

forming a trench in a metal stripe of a dual damascene line;

depositing a barrier layer in the trench;

filling a remainder of the trench with metal; and

forming a second trench, wherein at least a portion of the second trench extends through the barrier layer.

2. The method in accordance with claim 1 , wherein the forming of the trench comprises one of reactive ion etching and wet etching.

3. The method in accordance with claim 1 , further comprising:

polishing an upper surface of the metal filling the remainder of the trench to form a metal stripe in a smooth structure upper surface.

4. The method in accordance with claim 3 , further comprising:

depositing a cap layer over the smooth structure upper surface;

depositing an interlevel layer over the cap layer, wherein the second trench is formed in the interlevel layer.

5. The method in accordance with claim 4 , further comprising:

depositing a second barrier layer in the second trench;

filling a remainder of the second trench with metal; and

polishing an upper surface of the metal filling the remainder of the second trench to form a second metal stripe in a second smooth structure upper surface.

6. The method in accordance with claim 5 , further comprising:

depositing a second cap layer over the second smooth structure upper surface;

depositing a second interlevel layer over the second cap layer;

forming a third trench in the second interlevel layer, wherein at least a portion of the third trench extends through the second barrier layer;

depositing a second barrier layer in the third trench;

filling a remainder of the third trench with metal; and

polishing an upper surface of the metal filling the remainder of the third trench to form a metal stripe in a third smooth structure upper surface.

7. An interconnection structure formed according to the method of claim 1 .

8. A method for fabricating an interconnect structure, comprising:

forming a trench in a substrate;

depositing metal in the trench;

forming a second trench in the metal;

depositing a redundant liner in the second trench;

depositing metal in the second trench; and

forming a third trench in which at least a portion of the third trench extends through the redundant liner.

9. The method in accordance with claim 8 , further comprising:

depositing an interlevel layer over the substrate; and

forming the third trench in the interlevel layer.

10. The method in accordance with claim 9 , further comprising depositing metal into the third trench.

11. The method in accordance with claim 10 , wherein, prior to depositing the metal into the third trench, the method comprises depositing an interlevel layer barrier liner into the third trench.

12. A redundant structure formed in accordance with the method of claim 8 .