A method for manufacturing a microelectronic circuit includes the steps of providing a first wiring level comprising first wiring level conductors separated by a first wiring level dielectric material; forming a plurality of alternating layers of layer dielectric material and sacrificial material over the first wiring level; and forming a plurality of interconnect openings and a plurality of gap openings in the alternating layers of layer dielectric material and sacrificial material. The interconnect openings are formed over the first wiring level conductors. The method further includes forming (i) metallic conductors comprising second wiring level conductors, and (ii) interconnects, at the interconnect openings; and removing the layers of the sacrificial material through the gap openings.