US Patent 11923246 Via CD controllable top via structure

A method of via formation including forming a sacrificial mask over a conductive layer, forming a plurality of pillars in the sacrificial mask and the conductive layer, wherein each pillar of the plurality of pillars includes a sacrificial cap and a first conductive via, depositing a spacer between the plurality of pillars, masking at least one of the sacrificial caps, removing at least one of the sacrificial caps to create openings, forming second conductive vias in the openings, and depositing a dielectric coplanar to a top surface of the second conductive vias.