Fabrication and Characterization of a Planar Triode Structure Based on Honeycomb Carbon Nanotubes

We report a planar triode with metal-gate-free electrode based on carbon nanotubes. Excellent field emission properties with 1.4 mA/cm
²
at the gate voltage of 32 V are obtained. A turn-off phenomenon is observed when the gate voltage decreases to 0 V. The field emission at 1.2 mA/cm
²
is recorded for 20 h with the fluctuation of the emission current . The results would be of significance to the development of field emission triode structure in the future.