Title |
Electrical Variable Capacitor based on Symmetrical Switch Structure for RF Plasma System |
Authors |
Juhwa Min ; Beomseok Chae ; Hyunbae Kimand Yongsug Suh |
DOI |
https://doi.org/10.6113/TKPE/2019.24.3.161 |
Keywords |
EVC(Electrical Variable Capacitor) ; RF plasma system ; Voltage stress |
Abstract |
This study introduces a new topology to decrease the voltage stress experienced by a 13.56 MHz electrical variable capacitor (EVC) circuit with an asymmetrical switch structure applied to the impedance matching circuit of a radio frequency (RF) plasma system. The method adopts a symmetrical switch structure instead of an asymmetrical one in each of the capacitor’s leg in the EVC circuit. The proposed topology successfully reduces voltage stress in the EVC circuit due to the symmetrical charging and discharging mode. This topology can also be applied to the impedance matching circuit of a high-power and high-frequency RF etching system. The target features of the proposed circuit topology are investigated via simulation and experiment. Voltage stress on the switch of the EVC circuit is successfully reduced by more than 40%. |