Ion source operation with different magnetic confinement geometries

A comparison has been made between the longitudinal line cusp and the ‘‘continuous’’ checkerboard magnet geometries. We find that the checkerboard arrangement can provide a larger uniform density profile with approximately 20% less plasma density than the longitudinal line cusp. Results seem to indicate that the reduction in plasma density is closely related to the containment of primary ionizing electrons by the permanent magnets. A new magneto-electrostatic containment scheme was generated by using an internal magnetic cage system. The overall efficiency of this ion source was increased when it was operated with a xenon or argon plasma.