Time-resolved Langmuir probe measurements of the sheath dynamics and ion flux measurements in static and dynamic modes have been made. In the case of supersonic moving sheaths the experimental data qualitatively shows that the presheath is suppressed. The results of the sheath measurements are compared to a modified model description for the non-stationary sheath during plasma immersion implantation, which includes the suppression of the presheath at supersonic velocity of the plasma boundary.Analytical formulas are given for planar, cylindrical and spherical geometry. Reasonable agreement is obtained for spherical geometry according to a dome-like boundary around a small, flat substrate.

The design of a high-voltage pulsing system for a plasma immersion ion implantation (PIII) facility is presented. A list of requirements, which have to be fulfilled by a high-voltage pulse generator to get best results and a optimum operation of the PIII system, is given. A simple electrical model of the plasma is presented which describes the plasma as a capacitive–resistive load. The model parameters are determined to fit experimental results. The requirements for the pulse generator can be fulfilled well using a pulse generator design which employs a hard tube switch. A pulse generator design is presented which is especially optimized for PIII systems. The hard tube control is especially optimized for obtaining voltage rise times as short as possible.

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