Cobalt interconnect structure including noble metal layer

1. A process for forming a metal interconnect layer, the process comprising:

lithographically patterning and etching a dielectric layer to form one or more openings, wherein the one or more openings exposes a conductive region of an underlying interconnect structure or substrate;

conformally depositing a liner layer;

conformally depositing a noble metal layer onto the liner layer, wherein the noble metal layer comprises iridium or rhodium;

conformally depositing one or more layers of cobalt onto the noble metal layer; and

thermally annealing at a temperature and time effective to reflow the cobalt to at least partially fill the one or more openings to form one or more partially cobalt filled openings;

wherein the conformally deposited noble metal layer partially fills the one or more openings and exposing side surfaces.

2. The process of claim 1 further comprising filling the one or more partially cobalt filled openings with a metal comprising copper, aluminum, tungsten, nickel or alloys thereof.

3. The process of claim 1 , wherein conformally depositing the one or more layers of cobalt comprises a chemical vapor deposition process or an atomic layer deposition process.

4. The process of claim 1 , wherein the conformal liner layer comprises titanium, tantalum, tungsten, nitrides thereof or combinations thereof.

5. The process of claim 1 , wherein the dielectric layer comprises SiO 2 , silsesquioxanes, carbon doped oxides that include atoms of Si, C, O and H, thermosetting polyarylene ethers, or multilayers thereof.

6. The process of claim 1 , wherein the one or more openings in the metal interconnect layer comprises a via and a trench, wherein the metal interconnect layer comprises partially cobalt filled vias, completely cobalt filled vias, partially cobalt filled trenches and/or completely cobalt filled vias and trenches.

7. The process of claim 1 further comprising removing the liner layer from the exposed conductive region of the underlying interconnect structure or substrate subsequent to conformally depositing the liner layer.

8. The process of claim 6 further comprising depositing copper, aluminum, nickel tungsten or alloys thereof into unfilled or partially cobalt filled vias and trenches.

9. The process of claim 1 , wherein the temperature is from about 200° C. to about 900° C.

10. The process of claim 1 , wherein thermally annealing comprises furnace annealing at the temperature within a range of about 200° C. to about 350° C. for the time within the range of about 10 minutes to about 4 hours.

11. The process of claim 1 , wherein thermally annealing comprises laser annealing at the temperature within a range of about 350° C. to about 900° C. for the time within the range of about 50 nanoseconds to about 5 minutes.

12. The process of claim 1 , wherein the conformally deposited cobalt coats the inner sidewalls and the base of the noble metal layer.