US Patent 11594485 Local interconnect with air gap

An integrated circuit includes a base comprising an insulating dielectric. A plurality of conductive lines extends vertically above the base in a spaced-apart arrangement, the plurality including a first conductive line and a second conductive line adjacent to the first conductive line. A void is between the first and second conductive lines. A cap of insulating material is located above the void and defines an upper boundary of the void such that the void is further located between the base and the cap of insulating material. In some embodiments, one or more vias contacts an upper end of one or more of the conductive lines.