Field emission from carbon nanotube FEAs in hydrogen

Field emission in hydrogen at pressures near 10^-4 torr increases the current produced by carbon nanotube field emitter arrays. In this paper, a more detailed current and energy analysis including the effects of cracking the hydrogen using a hot filament, long-term exposure, and the production of ions is reported. The carbon nanotubes are grown using PECVD. With the gate voltage held at 24 V, the anode current increased from 0.4 μA before exposure to H, to 4 μA after half an hour under atomic hydrogen. Fowler-Nordheim analysis suggests a reduced work function or emitter radius and reduced emission area or reduced density of states.