Ultra small electron beam amplifiers

Data on field emission and microfabrication technologies relevant to the development of low-power electron-beam amplifiers and oscillators are discussed. The fabrication of a thin-film field-emission (TFFE) cathode for a 1-W electron-beam amplifier is examined. Some TFFE cathodes have been developed and tested in electron guns. Recent experimental results reveal that a beam can be formed from the field-emission cathode, and the TFFE cathode is applicable for devices operating below 3 kV at currents of less than 20 mA. The use of microfabrication techniques to construct slow-wave circuits is studied, and the use of finned structures as the slow-wave circuit for an electron-beam oscillator or amplifier is proposed.