Fore-Vacuum Ribbon Beam Plasma Electron Source Based on a Two-Stage Discharge System

We describe the design and main parameters of a fore-vacuum pressure, plasma-cathode electron source with an extended range of operating pressure. The source forms a ribbon electron beam with cross section 10 × 220 mm² over a pressure range from 10^–1 to 10 Pa. This wide pressure range is achieved by using two auxiliary hollow cathode discharge systems, between which there is a pressure difference. The beam current is up to 450 mA and the electron energy up to 8 keV. Inhomogeneity of the beam current density distribution is less than 15%. These beam parameters are advantageous for beam-plasma generation for the implementation of plasma chemical deposition of coatings.