Cobalt based interconnects and methods of fabrication thereof
An embodiment includes a metal interconnect structure, comprising: a dielectric layer disposed on a substrate; an opening in the dielectric layer, wherein the opening has sidewalls and exposes a conductive region of at least one of the substrate and an interconnect line; an adhesive layer, comprising manganese, disposed over the conductive region and on the sidewalls; and a fill material, comprising cobalt, within the opening and on a surface of the adhesion layer. Other embodiments are described herein.
1. An integrated circuit structure, comprising:
a dielectric layer;
an opening in the dielectric layer, the opening having an upper portion and a lower portion, the upper portion having a width greater than a width of the lower portion;
a cobalt plug in the lower portion of the opening;
a manganese-based adhesion layer on sidewalls of the upper portion of the opening and on the cobalt plug; and
a cobalt fill material in the upper portion of the opening and on the manganese-based adhesion layer.
2. The integrated circuit structure of claim 1 , wherein the cobalt plug comprises at least 50% cobalt.
3. The integrated circuit structure of claim 2 , wherein the cobalt plug further comprises one or more of Al, Ni, Cu, Ag, Au, Mn, Ti, V, Cr, Fe, Ta, W or Ru.
4. The integrated circuit structure of claim 1 , wherein the cobalt plug comprises at least 90% cobalt.
5. The integrated circuit structure of claim 4 , wherein the cobalt plug further comprises one or more of Al, Ni, Cu, Ag, Au, Mn, Ti, V, Cr, Fe, Ta, W or Ru.
6. The integrated circuit structure of claim 1 , wherein the manganese-based adhesion layer comprises a material selected from the group consisting of Mn, MnN, MnSixNy, and MnSixOy.
7. The integrated circuit structure of claim 1 , wherein the cobalt fill material consists essentially of cobalt.
8. The integrated circuit structure of claim 1 , wherein the cobalt fill material comprises 95+% cobalt with the remainder comprising one or more of Al, Ni, Cu, Ag, Au, Mn, Ti, V, Cr, Fe, Ta, W or Ru.
9. The integrated circuit structure of claim 1 , wherein the cobalt fill material comprises a material different than the cobalt plug.
10. The integrated circuit structure of claim 1 , wherein the cobalt fill material consists essentially of cobalt, the cobalt plug comprises at least 50% cobalt, the manganese-based adhesion layer comprises a material selected from the group consisting of Mn, MnN, MnSixNy, and MnSixOy, and wherein the cobalt fill material comprises a material different than the cobalt plug.