Investigation of FEAs applied in electron gun for microwave tubes

Our previous research showed that the main technical difficulties employing field emission arrays (FEAs) in electron gun of microwave power amplifiers could be attributed to the FEAs' emission current density, emission stability and the defocus of the electron beam. The investigation of such factors are described in this paper. The current density of about several A/cm/sup 2/ and its stable working are studied and obtained. An electron gun with FEAs for microwave tubes is designed and simulated, which allows focusing of a 100 mA electron beam with a maximum 30/spl deg/ scattered angle.