Best impedance matching seeking of capacitively coupled plasmas by numerical simulations*

Impedance matching can maximize the absorbed power transferred to the plasma load and minimize the reflected power, so it is critical and indispensable for capacitively coupled plasmas (CCPs). A self-consistent numerical method for coupling generalized external circuit and electrode driven plasma is proposed. The plasma is solved by a 1D PIC-MCC model, and the external circuit is solved by Kirchhoff's law. The circuit and plasma are coupled self-consistently. Based on the above method, we propose an impedance matching design method for single-frequency CCPs and tailored voltage waveform CCPs, which also has been studied by many scholars ^[1,2]. The selection method of matching network topology and the design process of matching parameters are studied in detail. The proposed method can be used to calculate the matching parameters in any condition consistently. The design method and iteration process of matching parameters are demonstrated by a simulation example of argon discharge. Through impedance matching design, the reflection coefficient of each frequency component can be reduced to a relatively low level, and the power absorption efficiency of the plasma load can reach the level of nearly 40%, which provides strong references for practical industrial design. The results show that impedance matching network plays an important role in discharge ^[3] and breakdown process ^[4].