Copper deposition for filling features in manufacture of microelectronic devices

A method for metallizing an electrical interconnect feature with copper, the electrical interconnect feature being located in a dielectric material on a semiconductor integrated circuit device substrate, wherein the dielectric material has a top-field surface and the electrical interconnect feature has a bottom, a sidewall having a depth and a top opening having an opening dimension, the method comprising:

• in sequence,
• forming a deposit of copper wettable metal, wherein said forming said deposit is by a process selected from the group consisting of physical vapor deposition (PVD), plasma-enhanced physical vapor deposition (PE-PVD), chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PE-CVD), and atomic layer deposition (ALD), wherein the copper wettable metal is ruthenium;
• forming a copper-based deposit on the top-field surface and a copper seed layer on the bottom and the sidewall of the interconnect feature, wherein said forming comprises a process selected from the group consisting of physical vapor deposition (PVD), plasma-enhanced physical vapor deposition (PE-PVD), chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PE-CVD), and atomic layer deposition (ALD);
• partially filling the interconnect feature by electrolytic Cu deposition;
• dissolving a portion of the copper seed layer to thereby form an initial metal profile comprising copper metal deposited on the bottom of the electrical interconnect feature and a segment of the sidewall having essentially no copper thereon, wherein said dissolving is performed by anodic dissolution, and wherein said dissolving also dissolves said copper based deposit on the top-field surface in addition to said dissolving the portion of the copper seed layer;
• and
• filling the electrical interconnect feature having the initial metal profile therein with copper to thereby metallize the electrical interconnect feature, wherein said filling comprises electroless Cu deposition.