Focused electron beam in guns with a plasma emitter: study and application

Authors: Kornilov S. Yu., Rempe N. G.

Annotation: The paper presents the results of latest research, devoted to the study of the features of the electron-optical system with a plasma emitter, and aimed at the forming of focused electron beams with a small diameter. It is shown that the beamforming in the electron-optical system with a plasma emitter occurs in a magnetic field penetrating from the discharge chamber. The results of calculations of this field are presented. It is found that the beam focusing can be significantly improved by producing a quasi-uniform magnetic field in the electron–optical system with a plasma emitter. The mechanisms of gas influence on the energy inhomogeneity of the beam and its current in the regions of beam primary formation, acceleration, and transport are described. The measurement results for the brightness of an electron beam from gun with a plasma emitter are presented. The brightness of the focused beam of a gun with a plasma emitter is not inferior to the brightness of beams in guns with a hot cathode. The results of studies aimed at creating a device to extract the electron beam to the atmosphere, for gun with a plasma emitter, are presented. It is shown, that the pressure drop to the atmospheric one in the system of electron beam extraction to the atmosphere, can be ensured by two gas-dynamic window stages evacuated by pumps with optimal performance. The construction of a device for electron-beam transportation to the atmosphere is described and its key characteristics are presented. The experience results of both the technological application of guns with a plasma emitter and in the structure of research facilities are given.

Keywords: gun with a plasma emitter, electron-optical system, electron beam, plasma emitter, focusing, electron-beam technologies