Fabrication and characterization of carbon nanotube arrays using sandwich catalyst stacks

A novel synthesis of carbon nanotubes for field-emitter arrays with a uniform field emission current is reported. Microwave plasma chemical vapor deposition and a unique structure of a sandwich catalyst stack are used to grow vertically aligned carbon nanotubes with a high density, uniform length and diameter. After being etched in a H2/N2-microwave plasma, the overall field emission current density from the prepared emitter arrays is 1.2 A/cm2 at an electric field of 6.5 V/μm with stable and uniform emission characteristics. The threshold field is 3.2 V/cm, defined at an emission current density of 10−6 A/cm2.