Electrostatic Beam Focusing of Carbon Nanotubes Electron Source

In this paper, we present the realization and characterization of a carbon nanotubes (CNTs) electron gun. The gun consists of a CNT cathode with an external extracting grid, that reached a maximum current density of 0, 6 A/cm \(^{\mathrm {\mathbf {2}}}\) , assembled with an electrostatic focusing grid. The realized compact electron gun achieved a maximum output current density of 0, 11 A/cm \(^{\mathrm {\mathbf {2}}}\) . This represents one of the first examples of a CNTs electron gun with an electrostatic focusing grid with high-output current density. The assembly process and the relative issues are described in detail together with the field emission characteristics of the cathodes and of the electron gun.