Design of a sheet-beam electron gun for a Ka-band microfabricated traveling-wave tube

A novel design of a sheet beam electron gun, suitable for a Ka-band microfabricated traveling-wave tube (TWT), is described in this paper. Simulations take into account emission from a CNT field-emitter array (FEA) and the formation of the sheet beam. The rectangular FEA cathode of 2250×300 µm 2 area produces a 10 mA sheet electron beam which is compressed into a 350×150 µm 2 area. The configuration of the focusing electrodes and the anode is suitable for microfabrication. For an anode voltage of 3.7 KV, the presented simulation results show a uniform beam at the anode output.