For production of ionized atom fluxes a method of evaporating materials in vacuum by means of non-self-maintained discharge was developed. The conditions of the initiation discharge were examined. The necessary conditions are attainment of fixed vapor or gas pressure between the electrodes and presence of pre-breakdown current. The characteristics of the discharge in the voltage range from 30 to 700 V with currents of 1 to 50 A were investigated. The discharge plasma was studied with the assistance of electrostatic probes. The considered discharge region occupies the transition region from glow to arc. The cathode temperature is one of the fundamental parameters which defines the type of discharge and its burning. The regulation of temperature and discharge power influences on the processes which proceed on the cathode and in the space between the electrodes. The operation in different regimes results in the ability to control of ionization degree from 2 to 100%.
M. M. Nikitin,
"Non-self-maintained discharge in vacuum", Proc. SPIE 2259, XVI International Symposium on Discharges and Electrical Insulation in Vacuum, (1 May 1994); doi: 10.1117/12.174545; https://doi.org/10.1117/12.174545