Discharge Plasma Parameters of Magnetron Sputtering System in Gas and Vacuum (Gasless) Operating Modes

We present the results of probe measurements of plasma parameters and ion mass-to-charge state of a DC magnetron sputtering system (MSS) in gas and vacuum (gasless) operating modes at operating pressures from 2 down to 0.05 mTorr. It is shown that, in comparison with the gas operating mode, the discharge plasma of the vacuum magnetron is characterized by higher values of electron temperature and plasma potential, along with the generation of multiply charged metal ions of the target material. This mode is also characterized by a higher degree of ionization of sputtered material and enhanced ion current density onto the substrate. The revealed differences may be useful for improving quality and properties of formed coatings.