Anin situinvestigation of electromigration in Cu nanowires

Abstract

Electromigration in copper (Cu) nanowires deposited by electron beam evaporation has been investigated using both resistance measurement and the in situ scanning electron microscopy technique. During electromigration, voids formed at the cathode end while hillocks (or extrusions) grew close to the anode end. The failure lifetimes were measured for various applied current densities and the mean temperature in the wire was estimated. Electromigration activation energies of 1.06 eV and 0.94 eV were found for the wire widths of 90 nm and 141 nm, respectively. These results suggest that the mass transport of Cu during electromigration mainly occurs along the wire surfaces. Further investigations of the Auger electron spectrum show that both Cu atoms and the surface contaminants of carbon and oxygen migrate from cathode to anode under the electrical stressing.

One hundred fold increase in current carrying capacity in a carbon nanotube–copper composite

“…Further, we note that this estimation of the activation energy ( E a ) is independent of the choice of pre-exponential factor ( A ) and current-density exponent ( n ). The value of 2.03 eV was identical to that of Cu lattice diffusion172829 (∼2.0–2.3 eV), which means that the Cu diffusion follows the most difficult pathway. For bulk Cu, diffusion occurs at the surfaces and grain boundaries that possess much lower activation energies172829 (∼0.7 eV and ∼1.0 eV, respectively).…”

“…The value of 2.03 eV was identical to that of Cu lattice diffusion172829 (∼2.0–2.3 eV), which means that the Cu diffusion follows the most difficult pathway. For bulk Cu, diffusion occurs at the surfaces and grain boundaries that possess much lower activation energies172829 (∼0.7 eV and ∼1.0 eV, respectively). Our results showed that for the CNT–Cu composite, the Cu diffusion pathways through surface and grain boundaries were greatly suppressed.…”

“…1g). These results demonstrate that Cu had diffused away from this region and that the failure mechanism of the CNT–Cu composite was Cu electromigration272829.…”

Annealing-induced enhancement of ferromagnetism in SnO2-core/Cu-shell coaxial nanowires

“…On the other hand, copper (Cu) nanowires have many useful physical properties, such as their low electrical resistivity and low cost, and they are particularly suitable for *Corresponding author: hyounwoo@hanyang.ac.kr ©KIM and Springer applications in nanodevices [37]. In ultra-large-scale integration (ULSI) circuits, Cu has been widely used for interconnects to reduce the resistance-capacitance delay, the amount of electromigration, and the cost of fabrication [38]. Also, Cu doping has been studied for a variety of applications, including Cu-doped ZnO nanowires for photodetectors [39] and ferromagnetism [40,41].…”

Preparation and annealing of GaN/Cu core-shell nanowires

“…On the other hand, copper (Cu) nanowires display many useful physical properties; they are particularly suitable for applications in nanodevices owing to their low electrical resistivity and low cost [15]. For example, Cu has been widely used as ultra-large-scale integration (ULSI) interconnects to reduce the resistance-capacitance delay, the amount of electromigration, and the cost of fabrication [16]. Cu doping has been studied for a variety of applications, including Cu-doped ZnO nanowires for photodetectors [17] and ferromagnetism [18,19].…”