The role of the field emission effect in direct-current argon discharges for the gaps ranging from 1 to 100 µm

Abstract

Abstract This paper contains results of experimental and simulation studies of the direct-current breakdown voltage curves in argon discharges with parallel-plane electrodes separated from 1 to 100 µ m. The negative slope of the Fowler–Nordheim plot indicates that the current flow is due to field-emitted electrons. Based on the breakdown voltage curves, the effective yield has been estimated. The secondary electron emission in microgaps depends primarily on the electric field E rather than reduced electric field E / N , leading directly to the violation of Paschen's law. The obtained results provide better insight into the role of the enhancement of the secondary electron emission due to high electric field generated in microgaps. Due to the lack of experimental data in microgaps, there are only a few values for the effective yield and no value for argon. By fitting presented experimental data, realistic values of the effective yield in microgaps are obtained and used for the calculations of the breakdown voltages representing basic design data of high-voltage equipment.