Low Resistivity Tin-Doped Copper Nanowires

This letter presents Sn-doped Cu nanowires, Cu(Sn) NWs, synthesized by chemical vapor deposition using Cu and ${\rm SnCl}_{2}$ powders as precursors at low temperature $({\leqq}{400}^{\circ}{\rm C})$ and their electrical properties. The Sn not only plays a role as a catalyst to enhance reduction of Cu, but also as a dopant for Cu(Sn) NWs. The Sn thickness, substrate pretreatment, substrate temperature, process pressure, and precursor compositions are optimized to obtain high-density nanowires. Results show that Cu(Sn) NWs, 30 $\mu{\rm m}$ in length and 50–620 nm in diameter, are synthesized successfully at 350 $^{\circ}{\rm C}$ . The Cu(Sn) NWs exhibit low resistivity (2.84 $\mu\Omega \hbox {-}{\rm cm}$ ), which is the lowest value reported thus far, and a failure current density of $3.16\times 10^{7}~{\rm A}/{\rm cm}^{2}$ .