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A 2.45 GHz electron cyclotron resonance test stand based on a pure volume H− negative ion production is presently running at CEA Saclay. This negative ion source (ECRIN) is working in pulsed mode, up to 10 ms at 10 Hz. Several modifications allowed increasing the extracted H− current from the source. Those results will be summed up in the first part. With the experience collected from this source, a second one using a multi‐cups magnetic structure is under development. Magnetic calculations and simulations showed that an octupolar configuration could allow improving the H− ion production. Those simulations will be discussed and the new set up will also be presented. The source is now being assembled on a new test bench, called BETSI, for light ion source development based on permanent magnet structure.

In order to make a reliable H− ion source, a hybrid PIC 2D MCC 3D fluid code has been developed. The aim of the code is to study the effect of electron injection into a cylindrical gas chamber. This new version takes into account the 2D space charge distribution. Thus, it is possible to calculate the H− ion distribution everywhere in the plasma chamber. Many results have been brought as well as the best injected energy and the electron penetration length efficiency. Moreover, the calculations explain why it is more problematic to get an efficient volume production at high pressure (100 mTorr) than at low pressure (6 mTorr). The temporal H− production evolution is finally discussed.

At CEA‐Saclay, in 2003, the new 2.45 GHz ECR source, based on pure volume H− ion production, showed a dramatic increase of the H− extracted ion beam. In fact, since the rectangular plasma chamber is separated in two different parts by a stainless steel grid, the extracted H− current rose from few μA to 1.5 mA. Of course the grid position and its potential with respect to the plasma chamber were optimised. Ceramic plates allow increasing the electron density and lead to an improvement of the negative ion production. Plasma characterization by using Langmuir probes and positive charge analysis are also presented. The last results are reported and discussed. This work is part of the High Performance Negative Ion Sources (HPNIS) program and supported by the European Union under contract HPRI‐CT‐2001‐50021.