Ion Composition of Plasma of a Planar Magnetron in the Gaseous and Vacuum Modes of Operation

Results of experimental study and numerical simulation of the fractional content of argon and copper ions in plasma generated in a direct-current planar magnetron with a copper target in the gaseous (at argon pressure at the level of 0.1 Pa) and vacuum (at residual-gas pressure of 0.004 Pa) operation modes are presented. It is demonstrated that fractions of copper ions in the gaseous and vacuum operation modes at the discharge current, sufficiently high for sustaining the self-sputtering regime (10 A), are close to each other and are equal to 97 and 100%, respectively. The results of experiments and numerical estimates are indicative of the possibility of achieving a stable continuous discharge and obtaining a flow of metal ions in high vacuum in a planar magnetron without effects of thermal evaporation or sublimation of the copper target.