Investigation of plasma characteristics in an unbalanced magnetron sputtering system

Plasma Physics Reports (Impact Factor: 0.75). 05/2009; 35(5):399-408. DOI: 10.1134/S1063780X09050055

ABSTRACT Results are presented from experimental studies of a magnetron sputtering system for different configurations of the magnetic
field above the cathode surface. The current-voltage characteristics of a magnetron discharge at different working gas pressures
(0.08–0.3 Pa) and currents in the unbalancing coil were studied. The production and transport of charge carriers in a magnetron
discharge with an unbalanced magnetic field was investigated by means of probe measurements of plasma characteristics and
ion energies in the region between the substrate and the magnetic trap at the cathode surface. The radial distributions of
the ion current density, plasma potential, and floating potential in the unbalanced operating mode are found to have pronounced
extrema at the magnetron axis. It is shown that the plasma density near the substrate can be increased considerably when the
axial magnetic field is high enough to efficiently confine plasma electrons and prevent their escape to the chamber wall.

PACS numbers52.50.Dg-52.70.Ds-52.77.Dq

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Available from: A. A. Solov’ev, Jun 19, 2015
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