Etch stop layer-based approaches for conductive via fabrication and structures resulting therefrom

An integrated circuit structure, comprising:

• a plurality of conductive lines in an inter-layer dielectric (ILD) layer above a substrate;
• a hardmask layer on the plurality of conductive lines and on an uppermost surface of the ILD layer, the hardmask layer comprising a first hardmask component on and aligned with the uppermost surface of the plurality of conductive lines, and a second hardmask component on and aligned with regions of the uppermost surface of the ILD layer, the first and second hardmask components differing in composition from one another, and the first hardmask component comprising a lower etch stop layer and an upper layer different from the lower etch stop layer, the lower etch stop layer confined to the uppermost surface of the plurality of conductive lines;
• and
• a conductive via in an opening in the hardmask layer and on a portion of one of the plurality of conductive lines.

A method of fabricating an integrated circuit structure, the method comprising:

• forming a plurality of conductive lines in an inter-layer dielectric (ILD) layer above a substrate, wherein each of the plurality of conductive lines has a bulk portion comprising a metal;
• treating the plurality of conductive lines to form an uppermost surface comprising the metal and a non-metal;
• forming a hardmask layer on the plurality of conductive lines and on an uppermost surface of the ILD layer, the hardmask layer comprising a first hardmask component on and aligned with the uppermost surface of the plurality of conductive lines, and a second hardmask component on an aligned with regions of the uppermost surface of the ILD layer, the first and second hardmask components differing in composition from one another;
• forming an opening in the hardmask layer exposing a portion of one of the plurality of metal lines;
• modifying the exposed portion of the one of the plurality of metal lines to remove the non-metal from the uppermost surface of the exposed portion of the one of the plurality of metal lines;
• and
• forming a conductive via in the opening in the hardmask layer and on the modified exposed portion of the one of the plurality of conductive lines.