Abstract: An ECR (Electron Cyclotron Resonance) ion source includes a plasma chamber having a circular cylindrical cross-section, magnets for generating a magnetic field for confinement of the plasma in the plasma chamber, and a microwave generator disposed outside the plasma chamber and generating at least two microwave signals. Several antennas protrude radially into the plasma chamber with a predetermined angular offset ?. The antennas receive phase-shifted microwave signals from the microwave generator and radiate linearly polarized microwaves, which in turn produce a circularly polarized microwave inside the plasma chamber. A method for operating an ECR ion source is also described.

Abstract: An ECR (Electron Cyclotron Resonance) ion source includes a plasma chamber having a circular cylindrical cross-section, magnets for generating a magnetic field for confinement of the plasma in the plasma chamber, and a microwave generator disposed outside the plasma chamber and generating at least two microwave signals. Several antennas protrude radially into the plasma chamber with a predetermined angular offset ?. The antennas receive phase-shifted microwave signals from the microwave generator and radiate linearly polarized microwaves, which in turn produce a circularly polarized microwave inside the plasma chamber. A method for operating an ECR ion source is also described.