A Study of the Factors Influencing Multipactor to Low-Pressure Gas Discharge

Multipactor and low-pressure gas discharges have a negative impact on the performance and security of microwave components in space. In this manuscript, a 2-dimensional parallel flat plate structural model was designed to simulate the breakdown of multipactor to low-pressure gas discharges. The breakdown levels in the pressure range of 0.1 to 100 torr were verified under the conditions of the Ag material, 4-mm gap, 2.6-GHz frequency, and air as the background gas. Random secondary electron emission and gas molecule collision processes are incorporated, and the effect of their transition section is studied using trajectory tracking and Monte Carlo methods. A comparison of the model to the available experimental data demonstrates the model’s accuracy. On this basis, the variation of gas adsorption in relation to the surface secondary electron yields was considered, and the effect of the gas adsorption issues on breakdown level was calculated by means of numerical simulations based on some assumptions. The calculation reveals that in a finite volume of space, smaller desorption volumes cause negligible pressure changes, but the secondary electron emission capacity of the material decreases, which, in turn, leads to a flat or rising breakdown level. On the contrary, the larger the desorption volume, the more the gas is collisionally ionized and the breakdown level decreases.