Direct ion content measurements in a non-sputtering magnetron discharge

In present contribution we report the first direct measurements of ion fluxes in a non-sputtering magnetron discharge (NSMD) with Al cathode in Ar/O2 mixtures. The diagnostic unit comprising three-electrode electrostatic lens ion extractor, magnetic sector mass-analyzer, and a vacuum electron multiplier was calibrated and then used to record the time-resolved ion counts of Al+ and Ar+ both in NSMD and arc regimes. The results clearly indicate that in NSMD the dominant species are Ar ions while Al ion signal is lower than the sensitivity limit due to noise level, in contrast to the arc discharge. The capabilities of the diagnostics setup and its sensitivity limits are discussed.