Method of depositing a uniform barrier layer and metal seed layer with reduced overhang over a plurality of recessed semiconductor features

A method of depositing a metal seed layer on a substrate comprising a plurality of recessed device features, the method comprising:

• (a) depositing a first portion of a barrier layer onto the substrate in a manner which produces substantially no overhang at an opening present in an upper surface of the recessed device features, using sufficiently low bias that the bottom surface of the recessed device features in the substrate is not resputtered in any amount which would be harmful to device feature performance;
• (b) sculpturing deposited barrier layer material using ion deposition sputtering with sufficiently high substrate bias that there is a net loss in the thickness of the barrier layer at the upper surface of the recessed device features, while there is a net gain in the thickness of the barrier layer on the sidewalls and at particular locations on the bottom surface of the recessed device features;
• (c) depositing a first portion of the metal seed layer onto the substrate in a manner which produces substantially no overhang at an opening present in an upper surface of the recessed device features, using sufficiently low substrate bias that the metal seed layer deposited on a bottom surface of the recessed device features is not resputtered in any amount which would be harmful to device feature performance;
• and
• (d) sculpturing deposited metal seed layer using ion deposition sputtering with sufficiently high substrate bias that there is a net loss in the thickness of the metal seed layer at the upper surface of the recessed device features, while there is a net gain in the thickness of the metal seed layer on the sidewalls and at particular locations on the bottom surface of the recessed device features.