US Patent 11189528 Subtractive RIE interconnect

A method is presented for constructing interconnects by employing a subtractive etch process. The method includes forming a plurality of first conductive lines within an interlayer dielectric, depositing dielectric layers over the plurality of first conductive lines, depositing a photoresist layer over the dielectric layers, patterning the photoresist layer to create vias to top surfaces of one or more of the plurality of first conductive lines, and depositing a conductive material such that the conductive material fills the vias and provides for a sheet of metal for second conductive lines formed above the first conductive lines.