Pulse Current Generator with Improved Waveform Fidelity for High Voltage Capacitively-Coupled Plasma System

This paper proposes a novel structure of power converter solution on the basis of current source type topology for a highly capacitively-coupled plasma application system. In overall system, two current sources are connected in parallel to generate the different output current of high precision in different switching intervals. The overall system consists of four major functional blocks; bias current generator, bias current modulator, slope current generator, and slope current modulator. The proposed solution also employs SiC MOSFET type power semiconductor switch of 1200V/90A in order to meet the fast transient requirement. The proposed converter system successfully satisfies the specification of output voltage of 4.5kV and output current of 40A with the rising/falling time of less than 100ns. This proposed topology makes it possible to accurately shape the output load voltage in a highly capacitively-coupled plasma application system with reduced level of voltage spike and distortion as compared to the state-of-the-arts solutions of voltage source type converters.