A double-plasma source of continuous bipolar ion-ion beam

A double-plasma source capable of the generation of a continuous bipolar ion-ion beam is described. The quasi-neutral ion-ion flow to an extraction electrode is formed in the system containing primary inductively coupled plasma separated from a secondary plasma by an electrostatic grid-type filter. The total current of each ion species to the 250mm diameter extraction electrode is about 80mA; the electron current does not exceed 30% of the ion current. Method of positive/negative ion current ratio control is proposed, allowing the ion currents ratio variation in wide range. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4788711]