A method for fabricating large-area, patterned, carbon nanotube field emitters

Abstract

A method for fabricating large-area patterned carbon nanotube field emitters is reported. Carbon nanotube films were prepared by first depositing and patterning a transition metal catalyst film on a substrate and then by heating the substrate in a hydrocarbon atmosphere. The catalytically grown carbon nanotube films had a high emission current density of about $\text{100–1000\hspace{0.05em}}{\mathrm{mA cm}}^{\mathrm{-2}}$ at a low macroscopic electric field of $\text{10–15\hspace{0.05em}}{\mathrm{V \mu m}}^{\mathrm{-1}}.$ Electron emission from the carbon nanotube films was observed at a macroscopic electric field of $\text{1–5\hspace{0.05em}}{\mathrm{V \mu m}}^{\mathrm{-1}}.$ The $\mathrm{I–V}$ curve obeyed the Fowler–Nordheim (FN) relationship at low emission current density, but at high electric field, the $\mathrm{I–V}$ curve deviated from the FN relationship due to defects on the tip of the catalytically grown carbon nanotubes. The catalytic growth of carbon nanotubes offers an inexpensive and controllable process to produce a uniform, high density of emitters on large substrate surfaces.