Resistivity scaling study of topological CoSi wires for interconnects beyond copper

We experimentally demonstrate the nanoscale resistivity‑scaling behavior of topological conductors using cobalt monosilicide (CoSi) nanowires (NWs) fabricated on 200 mm wafers with CMOS‑compatible processes. Both templated near‑epitaxial and polycrystalline CoSi NWs are evaluated, with cross-sectional areas down to 35 nm² (~6 nm diameter). Unlike Cu, which shows steep resistivity increase below ~20 nm linewidth, templated near-epitaxial CoSi NWs show an exceptional ~80% resistivity reduction when the NW cross-sectional area scales below ~100 nm² as compared to micron-scale wires. Furthermore, resistivity of polycrystalline CoSi NWs with random grain orientations also approaches CoSi bulk single-crystal resistivity when the NW cross-sectional area scales below ~200 nm². These results provide wafer‑scale validation that topological conductors can enable interconnect scaling beyond Cu.