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Curved magnetic filters are often used for the removal of macroparticles from cathodic arc plasmas. This study addresses the need to further reduce losses and improving plasma throughput. The central figure of merit is the system coefficient Kappa defined as filtered ion current normalized by the plasma-producing arc current. The coefficient Kappa is investigated as a function of DC and pulsed magnetic field operation, magnetic field strength, external electric bias, and arc amplitude. It increases with positive filter bias but saturates at about 15 V for relatively low magnetic field (~10 mT), whereas stronger magnetic fields lead to higher Kappa with saturation at about 25 V. Further increase of positive bias reduces Kappa. These findings are true for both pulsed and DC filters. Bias of pulsed filters has been realized using the voltage drop across a self-bias resistor, eliminating the need for a separate bias circuit. Almost 100 A of filtered copper ions have been obtained in pulsed mode, corresponding to Kappa approximately equal to 0.04. The results are interpreted by a simplified potential trough model.

Ion plating has been introduced about four decades ago, and recently much progress has been made in deeper understanding of ion beam assisted and self-ion assisted deposition techniques. A variety of energetic deposition processes have been developed which involve either plasmas, or low-energy ion beams, or both. Of particular interest are hybrid processes such as plasma immersion techniques that have several energy and species "knobs" to tune and tailor properties of coatings, graded layers, and multilayers. These processes will be briefly reviewed. Increasing the energy of condensing species leads to the formation of intermixed layers, usually accompanied with improved adhesion. Energetic deposition often leads to high compressive stress; however, stress relief can be obtained under certain conditions, especially when using high-energy ions at low duty cycle. The choice of energy and duty cycle of the high-energy particle fraction is dictated, among other factors, by the average power limits, temperature tolerance of the substrate, and the effect of re-sputtering from the growing film.

A miniature multiple beamlet approach to an injector system was recently proposed in order to reduce the size, cost, and power requirements of the injector. The beamlets of very high current density are needed to meet the brightness requirement. Besides vacuum arc ion sources, cold-cathode gas ion sources are candidates for this application. Vacuum-arc metal ion sources and vacuum-arc-like gas ion sources are discussed. Experiments are presented that focus on the short-pulse plasma composition and ion charge state distribution. Mg and Sr have been identified as the most promising metals leading to mono-species beams when 20 mu s arc pulses are used. It is shown that the efficient production of gas ions requires the presence of a magnetic field.