Inverter plasma discharge system

We have developed a bipolar pulsed dc glow plasma discharge system using an inverter power supply. A target of the developed system is a low-cost surface modification operated in a low background pressure region (101–103 Pa) obtained with rotary pumps. In this pressure region, breakdown voltages for most gases have minimum values without the help of magnetic fields like a magnetron. Accordingly, we can use simple discharge electrodes such as parallel plates that would be extended for large area processing. These electrodes are driven by the bipolar voltage pulses including dc bias components which would drive both positive ions and electrons. A composition of the developed discharge system is shown. Voltage and current waveforms and emission light signals are measured to demonstrate a discharge operation. Initial applications of the developed system using a bipolar pulse processing technique are proposed.