Kinetic simulations of capacitively coupled plasmas driven by tailored voltage waveforms with multi-frequency matching

作者：Shimin Yu, Hao Wu, Shali Yang, Lu Wang, Zhipeng Chen, Zhijiang Wang, Wei Jiang, Julian Schulze, Ya Zhang · 发表于：Plasma Sources Science and Technology · 年份：2024 · DOI：10.1088/1361-6595/ad5df7 · 被引用次数：12 · 研究领域：Plasma Diagnostics and Applications、Particle accelerators and beam dynamics、Electrostatic Discharge in Electronics

Abstract Impedance matching is crucial for optimizing plasma generation and reducing power reflection in capacitively coupled plasmas (CCP). Designing these matchings is challenging due to the varying and typically unknown impedance of the plasma, especially in the presence of multiple driving frequencies. Here, a computational design method for impedance matching networks (IMNs) for CCPs is proposed and applied to discharges driven by tailored voltage waveforms (TVW). This method is based on a self-consistent combination of particle in cell/Monte Carlo collision simulations of the plasma with Kirchhoff’s equations to describe the external electrical circuit. Two Foster second-form networks with the same structure are used to constitute an L-type matching network, and the matching capability is optimized by iteratively updating the values of variable capacitors inside the IMN. The results show that the plasma density and the power absorbed by the plasma continuously increase in the frame of this iterative process of adjusting the matching parameters until an excellent impedance matching capability is finally achieved. Impedance matching is found to affect the DC self-bias voltage, whose absolute value is maximized when the best matching is achieved. Additionally, a change in the quality of the impedance matching is found to cause an electron heating mode transition. Poor impedance matching results in a heating mode where electron power absorption in the plasma bulk by drift e...