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 circu it configurations for the treatment of metals and polymer materials by plas ma immersion ion implantation are assessed. Both pulse generators were buil t 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 gen erator has a maximum capacity of 60 kV/10 A at a repetition frequency of 70 0 Hz with a long pulse rise time (of the order of 40 mus) 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 mus). 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 vol tage and implantation current from the application of both pulsers to a pla sma glow discharge are discussed using a stationary plasma circuit model. ( C) 2001 Elsevier Science B.V. All rights reserved.