MAGNETIC BIASING EFFECTS WHILE USING AN UNBALANCED PLANAR MAGNETRON

Magnetic biasing of a floating substrate affects the plasma of an unbalanced magnetron, changing the plasma distribution near the substrate and, therefore, varying the ion bombardment of the substrate. Biasing magnets which focus the plasma flow increase two parameters as measured by electrical probes located in the center of the sputtering zone: floating potential and ion current at the floating potential. Biasing magnets which defocus the plasma flow decrease the floating potential and ion energy flux, but cause little variation of the ion current. In both magnet configurations, a small plasma is confined near the top of the biasing magnets.