US Patent 11270913 BEOL metallization formation

A method is presented for back-end-of-the-line (BEOL) metallization with lines formed by subtractive patterning and vias formed by damascene processes. The method includes depositing a dielectric layer over a conductive layer formed over a substrate, forming spacers surrounding mandrel sections formed over the dielectric layer, selectively depositing gap fill material adjacent the spacers, selectively removing the spacers, etching the dielectric layer and the conductive layer to expose a top surface of the substrate, depositing and planarizing an interlayer dielectric, selectively forming openings in the dielectric layer, and filling the openings with a conductive material to define metal vias.