Gas breakdown in radio-frequency field within MHz range: a review of the state of the art

Low-temperature plasmas (LTPs) driven by 1–100 MHz radio-frequency (MRF) are essential for many industrial applications, and their breakdown characteristics are different to that of direct current (DC) breakdown. This review seeks to understand the state of the art of electric breakdown in the MRF field and provide references for related basic and applied research. We have given a brief history of research into MRF-driven breakdown, including Paschen curves, the corresponding discharge modes and parameter spaces, and the evolution of the parameters during the breakdown process. It is shown that the focus has been transferred from the breakdown voltage and V-I characteristics to the evolution of plasma parameters during the breakdown, both in experiments and simulations. It is shown that many fundamental and applied problems still need to be investigated, especially with the new global model and the incorporation of the external circuit model.