Abstract: Disclosed is a method of making a semiconductor structure, wherein the method includes forming an interlayer dielectric (ILD) layer on a semiconductor layer, forming a conductive plating enhancement layer (PEL) on the ILD, patterning the ILD and PEL, depositing a seed layer into the pattern formed by the ILD and PEL, and then plating copper on the seed layer. The PEL serves to decrease the resistance across the wafer so to facilitate the plating of the copper. The PEL preferably is an optically transparent and conductive layer.

Abstract: A chemical mechanical polishing (CMP) step is used to remove excess conductive material (e.g., Cu) overlying a low-k or ultralow-k interlevel dielectric layer (ILD) layer having trenches filled with conductive material, for a damascene interconnect structure. A reactive ion etch (RIE) or a Gas Cluster Ion Beam (GCIB) process is used to remove a portion of a liner which is atop a hard mask. A wet etch step is used to remove an oxide portion of the hard mask overlying the ILD, followed by a final touch-up Cu CMP (CMP) step which chops the protruding Cu patterns off and lands on the SiCOH hard mask. In this manner, processes used to remove excess conductive material substantially do not affect the portion of the hard mask overlying the interlevel dielectric layer.