Axial Distribution of the Ion Mass-to-Charge State in a Magnetron Discharge Plasma

The axial distribution of the ion mass-to-charge state in planar magnetron plasma has been studied. Copper is used as a target material, and argon was used as an operating gas. To study the ion mass-to-charge state, an upgraded quadrupole mass spectrometer was used. Measurements were carried out along the discharge system axis at a distance of 15 to 45 cm from the magnetron target. The operating pressure in a continuous mode was changed in the range from 1.2·10 –3 to 3·10 –3 Torr at discharge currents from 100 to 500 ma. It has been shown that at a distance of 15 cm from the magnetron, argon ions predominate in a fractional ratio. At the maximum distance, a significant copper ion fraction is observed. The fraction of argon ions decreases with increase in the discharge current and the operating pressure.