Enhanced field emission of thin multiwall carbon nanotubes by electron multiplication from microchannel plate

We report on a method to amplify electron emission from thin multiwall carbon nanotube (MWCNTs) field emitters using an electron multiplier microchannel plate. High density thin MWCNTs were synthesized by thermal chemical vapor deposition. Density of thin MWCNTs was increased by decreasing the amount of Al2O3 in the catalyst solution. The high density of nanotubes led to their vertical orientation. The thin MWCNTs showed low turn-on electric field and high electron emissivity which could be attributed to their wall thinness and high aspect ratio (similar to 1500) resulting in high field enhancement factor (similar to 9300). Emission current was stable with an average fluctuation of 2%. A microchannel plate positioned between cathode and anode increased the total emission current by 7.5 times. (c) 2006 American Institute of Physics.