Kinetic Simulations of Argon Microwave Microplasmas

Microwave microplasmas have been an active research area in the last decade with applications in various fields such as metamaterials and material processing. Low-frequency microwave microplasmas have been studied experimentally and numerically. Most of these numerical studies utilize continuum modeling while kinetic methods such as Particle-in-cell with Monte Carlo collisions (PIC-MCC) can most accurately capture the nonlinearities in microplasma behavior in this regime. On the other hand, microwave microplasmas with higher frequencies have been less explored. In this regard, in the current study, we perform 1-D PIC-MCC simulations for argon microplasmas in microwave regime for a range of frequencies to explore the effect of frequency on plasma characteristics such as number density and required power to reach a specific number density. In a recent work, we used PIC-MCC for microwave microplasma with a 0.5GHz frequency which showed good agreement with the existing literature. In another study, a comparison between PIC-MCC and an in-house fluid model illustrated reasonable agreement. Another objective of this work would be comparing PIC-MCC and fluid model for higher frequencies in order to assess the validity of the fluid model in predicting microplasma behavior.