Low-pressure high-current magnetron discharge with electron injection: From self-sputtering with multiply charged metal ions to non-sputtering with “pure” gas ions

We report our experimental investigations of the effect on the ion composition, including the ion mass-to-charge composition, of electron injection into the plasma of a high-current pulsed magnetron discharge in the ultra-low operating pressure range. We show that changing the magnetron discharge voltage by injecting additional electrons with adjustable current allows implementation of two operating modes: one with a plasma in which metal ions dominate (including multiply charged ions for certain target materials with low sputtering yield), and the other a magnetron non-sputtering mode with plasma of only gaseous ions. •We report our experimental investigations of the effect on the ion composition of electron injection into the plasma of a high-current pulsed magnetron discharge in the ultra-low operating pressure range (down to 0.2 mTorr).•We show that changing the magnetron discharge voltage by injecting additional electrons with adjustable current allows realize two operating modes.•In self-sputtering mode a metal ions dominate (including multiply charged ions for certain target materials with low sputtering yield).•In non-sputtering mode only gaseous ions is dominate in high-current low-voltage magnetron discharge.