Drive-in Mn Before Copper Plating

摘要

Techniques for forming Cu interconnects in a dielectric are provided. In one aspect, a method of forming a Cu interconnect structure includes: forming at least one trench in a dielectric; depositing a metal liner into the trench; depositing a Mn-containing seed layer on the metal liner within the trench; annealing the Mn-containing seed layer under conditions sufficient to diffuse Mn from the Mn-containing seed layer to an interface between the dielectric and the metal liner forming a barrier layer between the dielectric and the metal liner; and depositing Cu into the trench to form the Cu interconnect, wherein the Cu is deposited into the trench after the annealing is performed. The metal liner may optionally be reflowed such that it is thicker at a bottom of the trench than along sidewalls of the trench. A Cu interconnect structure is also provided.

主权项

1. A method of forming a copper (Cu) interconnect structure, the method comprising the steps of:
forming at least one trench in a dielectric; depositing a metal liner into the trench; depositing a manganese (Mn)-containing seed layer on the metal liner within the trench; annealing the Mn-containing seed layer under conditions sufficient to diffuse Mn from the Mn-containing seed layer to an interface between the dielectric and the metal liner forming a barrier layer between the dielectric and the metal liner; and depositing Cu into the trench to form the Cu interconnect, wherein the Cu is deposited into the trench after the annealing is performed.