Patent attributes
Self-aligned pitch split techniques for metal wiring involving a hybrid (subtractive patterning/damascene) metallization approach are provided. In one aspect, a method for forming a metal wiring layer on a wafer includes the following steps. A copper layer is formed on the wafer. A patterned hardmask is formed on the copper layer. The copper layer is subtractively patterned using the patterned hardmask to form a plurality of first copper lines. Spacers are formed on opposite sides of the first copper lines. A planarizing dielectric material is deposited onto the wafer, filling spaces between the first copper lines. One or more trenches are etched in the planarizing dielectric material. The trenches are filled with copper to form a plurality of second copper lines that are self-aligned with the first copper lines. An electronic device is also provided.