Numerical simulation study on discharge characteristics of the Dual hollow cathode plasma source using magnetic mirror field

Abstract The Dual hollow cathode plasma source uses hollow cathode cylindrical sputtering and ionizing metal elements, which has a high material utilization rate and has potential application in the field of material modification. Its performance index requires the cooperation of electrode discharge parameters and the rational utilization of the inner surface of the hollow cathode. In this paper, a two-dimensional fluid model of a Dual hollow cathode structure is developed to simulate the basic distribution of the Dual hollow cathode discharge, which fills the central region of the Dual hollow cathode structure and the electrons oscillate on the axis. The effects of electrode parameters and hollow cathode radius on the discharge were investigated. The results show that the radial electron density of the hollow cathode increases with increasing heated cathode voltage, but as the hot cathode voltage continues to expand beyond 1200 V this trend becomes less obvious. The enhancement of the wall ion current by the heated cathode voltage is very pronounced, and the hollow cathode discharge is the result of the mutual enhancement of the heated cathode voltage and the hollow cathode voltage. Hollow cathode sputtering needs to reach a voltage threshold of 300 V, and the existence of an optimal radius (r = 4 mm−6 mm) to achieve a high plasma density and at the same time favor hollow cathode sputtering.