INTEGRATED CIRCUIT HAVING IMPROVED ELECTROMIGRATION PERFORMANCE AND METHOD OF FORMING SAME
An aspect of the disclosure is directed to a method of forming an interconnect for use in an integrated circuit. The method comprises: forming an opening in a dielectric layer on a substrate; filling the opening with a metal such that an overburden outside of the opening is created; subjecting the metal to a microwave energy dose such that atoms from the overburden migrate to within the opening; and planarizing the metal to a top surface of the opening to remove the overburden, thereby forming the interconnect.
1 . An interconnect in an integrated circuit comprising:
an opening in a dielectric layer on a substrate; and
a metal layer substantially filling the opening,
wherein a concentration of vacancies within the metal layer is below an equilibrium concentration of vacancies within the metal layer.
2 . The integrated circuit of claim 1 , further comprising:
a liner layer substantially coating the opening; and
a seed layer substantially coating the liner layer within the opening and beneath the metal layer.
3 . The integrated circuit of claim 2 , wherein the liner layer includes at least one of: tantalum, tantalum nitride, tantalum-aluminum nitride, tantalum silicide, titanium, titanium nitride, titanium-silicon nitride, tungsten, cobalt, manganese, and ruthenium and
wherein the seed layer includes a copper seed layer.
4 . The integrated circuit of claim 1 , wherein the metal layer includes at least one of: copper, silver, cobalt, or gold.
5 . The integrated circuit of claim 1 , further comprising:
a dielectric cap layer over the metal layer.