Plasma ion source and method

摘要

A plasma ion source comprises a cathode chamber (1) with a gas input unit (2). A hollow cathode (3) forming an anode chamber (4) is connected with the cathode chamber (1) via the outlet made in the wall of the latter. The ion source structure includes an electrostatic system of ion extraction with an emission electrode (5) fixed in the anode chamber (4) outlet. With the help of a magnetic system, in the cathode (1) and anode (4) chambers the magnetic field is created with the induction vector of a preferably axial direction. An ignition electrode electrically connected with the hollow anode (3) is fixed in the cathode chamber (1). An additional electrode (10) is mounted in the outlet of the cathode chamber (1), which is insulated from the hollow anode (3) and the cathode chamber (1). The additional electrode (10) has an axial orifice with a diameter much smaller than the maximum internal cross section of the hollow anode (3). The electrical discharge between the cathode (1) and anode (4) chambers is ignited through the orifice. A particular ion source configuration and the oparation method correspond to the present invention and ensure increased energy and gas efficiency and high degree of uniformity of the generated ion current density.