Electron Cyclotron Resonance Multiply Charged Ion Sources

We describe three ion sources working in our laboratory that deliver multiply charged ion beams. All of them are E.C.R. ion sources and are characterized by the fact that the electrons are emitted by the plasma itself and are accelerated to the adequate energy through electron cyclotron resonance (E.C.R.). They can work without interruption during several months in a quasi-continuous regime. (Duty cycle: <.5). Their charge state distributions (C.S.D.) depend on the size and the characteristics of the plasma. For the smallest source the performances are comparable to those of P.I.G. sources. For the biggest source, the C.S.D. tend towards those obtained by EBIS-type sources. Experimental results and guiding ideas concerning these three ion sources are reviewed.