Carbon nanotube via interconnects with large current carrying capacity

We fabricated a carbon nanotube (CNT) via interconnect and evaluated its electrical properties. We found that the CNT via resistance was independent of temperatures, which suggests that the carrier transport is ballistic. From the via height dependence of the resistance, the electron mean free path was estimated to be about 80 nm, which is similar to the via height predicted for hp32-nm technology node. This indicates that it will be possible to realize CNT vias with ballistic transport for hp32-nm technology node and below. It was also found that a CNT via was able to sustain a current density as high as 5.0×10⁶ A/cm² at 105 °C for 100 hours without any deterioration.