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

Abstract

A two-dimensional fluid model of a double hollow cathode discharge structure constrained by a magnetic mirror field is established. The discharge is ignited by a hot cathode arc, and the length of the discharge arc column fills the entire central region of the double hollow cathode structure under the action of the magnetic field, with the electrons self-sustainedly oscillating on the axis. The electron density within the hollow cathode tube does not increase all the time with the arc voltage, the enhancement of the wall ion current by the arc voltage is very obvious, and the hollow cathode discharge is a result of the mutual enhancement of the arc voltage and the hollow cathode voltage. Hollow cathode sputtering needs to reach a certain voltage threshold to ensure that the inner wall has sufficient ion energy and that there exists an optimal radius range to maintain the discharge chamber to achieve a high plasma density and to favor hollow cathode sputtering.