ION SOURCE Russian patent published in 1996 - IPC

FIELD: devices producing ion beams. SUBSTANCE: ion source has hollow equipotential cathode, ring anode, magnetic system, multiaperture extraction system, auxiliary space, and cone. Working gas is admitted through sealed space 12 with annular exit clearance towards central rod 14 and through contracting slit 2, to space of hollow cathode 1. With voltage applied between anode 4 and cathode 1 in presence of radial magnetic field, main discharge is fired up between space 12 and anode. Ions produced in the process penetrate through contracting slits into hollow cathode 1 and cause firing of auxiliary discharge due to secondary electrons from walls of hollow cathode. Secondary electrons from cone 15 made of high-secondary-emission material move through slit 2 to anode and generate additional ions. Insert shape makes it possible to prevent distortion of full flux formed in hollow cathode. Insert is located in region where specific density of ions is maximal and where it can be intensively cooled down when active gases are used. In the case of inert gases, thermal emission and additional decrease in discharge voltage may be expected due to use of heat seal. EFFECT: extended service life and improved electric economic efficiency of ion source based on cold-cathode discharge contracted in crossed electric and magnetic fields. 2 cl, 1 dwg