• Applied Microscopy
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• v.46 no.4
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• pp.244-252
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• 2016

This paper describes a new design of carbon nanotube tip. $Nanocly^{TM}$ NC 7000 Thin Multiwall Carbon Nanotubes of carbon purity (90%) and average diameter tube 9.5 nm with a high aspect-ratio (>150) were used. These tips were manufactured by employing a drawing technique using a glass puller. The glass microemitters with internal carbon nanotubes show a switch-on effect to a high current level (1 to $20{\mu}A$). A field electron microscope with a tip (cathode)-screen (anode) separation at ~10 mm was used to characterize the electron emitters. The system was evacuated down to a base pressure of ${\sim}10^{-9}$ mbar when baked at up to ${\sim}200^{\circ}C$ overnight. This allowed measurements of typical Field Electron Emission characteristics; namely the current-voltage (I-V) characteristics and the emission images on a conductive phosphorus screen (the anode). Fowler-Nordheim plots of the current-voltage characteristics show current switch-on for each of these emitters.