Ion implantation by vacuum arc plasmas

Plasma immersion ion implantation (PILI) is a promising new method to modif y surfaces of materials by ion implantation. Pm works without expensive acc elerators and therefore this method should have the potential for more appl ications than conventional ion accelerators. By this method, the samples ar e immersed into a plasma and high voltage pulses are applied to it for extr acting ions from the plasma. Neither an extraction system nor other ion opt ics are needed. In addition to this great advantage, by using PIII, higher ion current densities and shorter implantation times are possible. The most commonly used plasma immersion arrangements extract the ion current from e xcited gases, especially from nitrogen; The vacuum are is an option to prod uce hydrogen-free carbon plasmas or metal vapor plasmas. These plasmas exte nd the possibilities of the immersion ion implantation considerably. For an efficient use of PIII in thin film technology, ion sources with currents h igher than 1.0 A are necessary. Moreover, the source has to be a compact to ol. We have developed an ion source based on a pulsed high current are. For the separation of the macroparticles, a magnetic plasma filter is used. Th e efficiency of the system was proved by implantation of carbon into silico n and niobium into a high-grade steel alloy. The implantation depths were 1 00 nm for carbon and 30 nm for niobium. (C) 1999 American Vacuum Society. [ S0734-211X(99)01602-9].