Plasma immersion ion implantation experiments with long and short rise time pulses using high voltage hard tube pulser

The performances of two high voltage pulse generators using different circuit configurations for the treatment of metals and polymer materials by plasma immersion ion implantation are assessed. Both pulse generators were built in the circuit category of hard tube type which uses a high power tetrode as a fast on–off switch to control the pulse duration. The first pulse generator has a maximum capacity of 60 kV/10 A at a repetition frequency of 700 Hz with a long pulse rise time (of the order of 40 μs) while the second one is able to operate with full voltage and current of 30 kV and 30 A at 1 kHz with a very short pulse rise time (less than 1 μs). It is shown that the better performance of the latter pulser in terms of rise time is due to a different configuration circuit employed in its construction. Target voltage and implantation current from the application of both pulsers to a plasma glow discharge are discussed using a stationary plasma circuit model.