Kinetic modeling of breakdown in sub-millimeter gaps in capacitively coupled plasma (CCP) devices

Anomalous arcing between different components can occur in various plasma sources, particularly when operating at increased power levels (e.g., current and voltage). In industrial capacitively coupled plasma (CCP) sources, various components made of different materials (e.g., insulators) are located around the powered and ground electrodes. Gas breakdown acts as a precursor to these anomalous arcing events. To investigate the physical mechanisms of breakdown, we use an idealized geometry for CCP devices. Sub-millimeter gaps between electrodes and guard rings where breakdown can occur are modeled in a two-dimensional PIC-MCC (Particle-in-Cell with Monte Carlo Collision) simulation. The kinetic modeling includes several key physical processes: electron-neutral collisions (elastic, excitation, ionization), electron- and ion-induced secondary electron emission (SEE), field emission with field enhancement, and surface charging. We will present the numerical results of single- and dual-frequency radiofrequency (RF) breakdown, compared with experimental data[1]. We will also discuss RF breakdown in the sub-millimeter gaps of CCP sources.

[1] Y. Yamashita, V. Sharma, S. Sriraman, and K. Hara, “Electron Monte Carlo simulations of single- and dual-frequency RF breakdown,” Physics of Plasmas, vol. 32, p. 043509, 04 2025