Semiconductor device and method for fabricating the same

1. A semiconductor device comprising:

a semiconductor substrate;

an interlayer dielectric layer having a damascene pattern on the semiconductor substrate;

a diffusion barrier comprising a trivalent material formed in the damascene pattern;

a seed layer formed on the diffusion barrier; and

a copper interconnection formed on the seed layer;

wherein the diffusion barrier comprises CoFeN.

2. The semiconductor device according to claim 1 , wherein the diffusion barrier comprises an amorphous trivalent material.

3. The semiconductor device according to claim 1 , wherein the diffusion barrier has a thickness of about 500 Å to about 1000 Å.

4. A method of fabricating a semiconductor device, comprising:

forming an interlayer dielectric layer on a semiconductor substrate;

forming a damascene pattern in the interlayer dielectric layer;

depositing a trivalent material on the interlayer dielectric layer to form a diffusion barrier;

depositing a seed layer on the diffusion barrier; and

filling a copper interconnection in the damascene pattern;

wherein the diffusion barrier comprises CoFeN.

5. The method according to claim 4 , wherein the diffusion barrier comprises an amorphous trivalent material.

6. The method according to claim 4 , wherein the diffusion barrier has a thickness of about 500 Å to about 1000 Å