Comprehensive modeling of microscale gas breakdown under extremely high electric field

We develop theoretical models for microscale breakdown under extremely high electric field conditions, by incorporating physical mechanisms associated with extremely strong electric fields, such as field emission, electron runaway, ion impact ionization, and the dynamics of fast atoms, which allows for accurate predictions of trends observed in existing experiments and simulations. Specifically, the mechanisms of breakdown characteristics exhibiting a multivalued curve in helium and a single-valued curve in argon are explicitly revealed. The results from the presented model also indicate that strong field-driven heavy particle reactions occur preferentially between smooth electrodes rather than rough electrodes in a microgap. Furthermore, simplified breakdown models tailored for argon and helium under strong field conditions are proposed after excluding less significant processes, providing theoretical references for the insulation design of miniaturized gaseous electronic devices.