Nanometer-level temperature mapping of Joule-heated carbon nanotubes by plasmon spectroscopy

We map the temperature distribution of suspended carbon nanotubes down to the 5-nm level inside a trans-mission electron microscope, by using electron energy-loss plasmon spectroscopy. The nanotubes are Joule heated in-situ, by individually contacting them using a biasing holder. The nanotubes can withstand current densities of over 5 x 107 A/cm2 and temperatures of over 2000 K without breaking. The temperature reaches its maximum around the nanoprobe contact, due to the comparatively large electrical resistance and small thermally-conductive area. The temperature remains high along the entire length of the CNTs, due to the excellent in-plane thermal conductivity (up to 2800 W/m/K) of the graphitic lattice. These results verify the expected robustness of these structures and confirm them as ideal candidates for applications as interconnects under extremely high current densities and temperatures.

Automated summary

We have mapped the temperature distribution of suspended carbon nanotubes at the 5-nm level inside a transmission electron microscope using electron energy-loss plasmon spectroscopy. The results show that these nanotubes can withstand extremely high current densities and temperatures, confirming them as ideal candidates for interconnects.