Controlled Growth of Oriented CoSi Nanowires in Dielectric Trenches via Chemical Vapor Deposition

Topological semiconductors such as CoSi are ideal candidates for back-end-of-line (BEOL) interconnects due to their surface-state-dominated transport and potential to suppress electron scattering. However, achieving single-crystalline and orientation-controlled growth on amorphous dielectrics such as $SiO{_2}$ remains challenge. In this work, we demonstrate the growth of CoSi nanowires in lithographically defined dielectric trenches using a dual-source chemical vapor deposition (CVD) approach, where $CoCl{_2}$ serves as the cobalt precursor and a sputtered thin layer of silicon provides the silicon source. This bottom-up strategy offers a promising route for integrating orientation-controlled topological interconnects in amorphous substrates.