Vacuum breakdown in microgaps between stainless-steel electrodes powered by direct-current and pulsed electric field

This paper reports on the variation of the physical properties of vacuum breakdown in microgaps from the static to the pulsed electric fields in a quasi-homogeneous electric field. The measurements were performed between the spherical cathode and planar anode, both made of stainless-steel separated from 1 mu m up to 10 mu m at the pressure of similar to 1 x 10(-4) Pa. Pulse rise time was varied gradually from fast 10(11) V/s down to 3 V/s. Several stages during pre-breakdown have been distinguished dependent on the pulse rise time from the recorded current-voltage characteristics. A detailed analysis of each pre-breakdown stage was based on the field emission theory. From the Fowler-Nordheim plots, the enhancement factor, the radius of the emitting area, and the maximum current density were calculated and subsequently substituted to the General Thermal-Field emission equation to estimate the dominating mechanism of the electron emission.

Automated summary

This study examines the variation of physical properties of vacuum breakdown in microgaps under different pulsed electric field conditions. Through analysis and calculation of multiple pre-breakdown stages, the dominant mechanism of electron emission was determined.