Field Emission of Individual Carbon Nanotubes in the Scanning Electron Microscope

Abstract

The field emission of individual multiwall carbon nanotubes grown by chemical vapor deposition was measured in a scanning electron microscope. By using a sharp anode, we were able to select one nanotube for measurements in carefully controlled conditions. Single nanotubes follow the Fowler-Nordheim law, and the dependence of the field enhancement with interelectrode distance and nanotube radius is in good agreement with the recent model of Edgcombe and Valdré. Our results suggest that only nanotubes with the highest field enhancement factors, i.e., at least 8x higher than those of the average nanotube population, contribute to the emitted current in usual large area measurements.

Self-Oscillations in Field Emission Nanowire Mechanical Resonators: A Nanometric dc−ac Conversion

“…17,18 The nanowire was manoeuvred in the vicinity of a metallic sphere that acted as an anode (Figure 2a). The anode or the tip was connected to either DC or AC sources as for the FE system.…”

Ageing effect on the field emission reproducibility of multiwalled carbon nanotubes

“…This may be understood if one considers the field enhancement effect and the MWCNT vacuum breakdown mechanism. According to Bonard et al [24], the MWCNTs with greater heights will contribute most to the FE current due to both the effects of field enhancement and electrostatic field screening. Furthermore, these highly emissive MWCNTs are liable to vacuum breakdown due to Joule heating [25,26].…”

Field emission from carbon nanotube fibers in varying anode-cathode gap with the consideration of contact resistance

“…The observed trend of increasing field enhancement factor with decreasing AK gap distance is in agreement with previous computational modeling 26 and experiments on CNT field emitters. 27 The drop of effective field enhancement factor for d = 1 mm and d = 1.25 mm is due to the possible change in the fiber morphology with the decreased gap, as noted in Refs. 13 and 14.…”