Outer Ring-Shaped Radio Frequency Magnetized Plasma Source for Target Utilization in Specific Area

A capacitively coupled radio frequency outer ring-shaped magnetized plasma discharge has been proposed with a concentrically monopole arrangement of magnets to erode the target in a specific area, especially, near the chamber wall. The three concentric monopole magnet arrangements with a center magnet and magnets in setups: 1) three circles; 2) two circles; and 3) one circle were investigated. From the magnetic flux lines profiles, it was found that the magnetic flux density in component parallel to the target surface has a peak magnitude in the outer circle of magnets for all setups. Ring-shaped plasma in the specific outer area was observed. The ion saturation current, I
_isat
were 0.6, 0.79, and 0.46 mA, for setups 1)-3), respectively, at r = 47 mm, where r = 0 mm is the center of the target. It was found that I
_isat
is very high in the outer target region near the chamber wall for setups 1) and 2), where I
_isat
for setup 3) decreases slowly. The results showed that the target utilization could be controlled in the outer specific area near the discharge chamber wall.