Origin of the Electric Property Change of a Single-Wall Carbon Nanotube Caused by Low-Energy Irradiation: Defects or Substrate Charging?

Abstract

Low-energy irradiation-induced conductivity decrease of a single-wall carbon nanotube has been well established experimentally. However, its origin is still controversial. Irradiation effects on suspended single-wall carbon nanotubes, which are much less affected by substrate charging effects, were studied to distinguish possible origins. The results indicate that the conductivity decrease is not caused by substrate charging, but by irradiation-induced defect formation.

Low-Energy Irradiation Damage in Single-Walled Carbon Nanotubes

“…Hobara et al, 2004. The irradiation conditions used in those studies (4 Ccm -2 of 20-keV and 20 Ccm -2 of 10-keV electrons) roughly correspond to 10 to 1000 fold of a value that can cause a SWCNT conductivity decrease of a few orders of magnitude (Suzuki, 2011). Thus, the damage seems to be specific to SWCNTs or thin CNTs with a diameter of 1 nm.…”

“…5. Here, I focus on the intensive irradiation effects I have studied by in-situ electric measurements during electron irradiation in a SEM equipped with piezo-actuated microprobes for electric measurements (Suzuki, 2011). The device used here consists of two SWCNTs (A branch is seen between the electrodes) suspended between the drain and source electrodes (height: 300 nm), as shown in Fig.…”