On the Ion Flux From Beam Plasma to a Metal Target Irradiated by a Pulsed Electron Beam in the Forevacuum Pressure Range

Abstract

We describe our investigations of the influence of electron beam parameters and working gas on the ion flux coming from the beam-produced plasma (beam plasma) to a target irradiated by a pulsed low-energy (up to 9 keV) electron beam in the forevacuum pressure range 4–15 Pa. The ion current from the beam-produced plasma to the target increases with increasing gas pressure and beam current, but decreases with increasing beam accelerating voltage. The use of gas with a greater ionization cross section leads to greater ion flux and correspondingly higher ion current to the irradiated target. The value of ion current to the target from the beam-plasma does not exceed 20% of the electron beam current. The observed dependencies of ion flux (current) to the target are due to changes in the beam-plasma density near the target. These results contribute to our understanding of the generation of beam-plasma by a pulsed electron beam and suggest the application of the ion flux from the beam-plasma to assist in electron-beam modification of dielectric materials in the forevacuum pressure region.