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Compact High-Density Plasma Source Produced by Using Standing Helicon Waves

High-density plasmas of the order of 1013 cm-3 are produced by the m=0 standing helicon wave (SHW) in a short discharge column (10 cm). Unlike conventional helicon wave discharges, high-density plasma production is split into two modes governed by N=1 and 3 (N is the number of half-wavelengths in the plasma column) SHWs. The external static magnetic field B0 dependence of plasma density np shows that N=3 SHW can produce a density higher than N=1 SHW at low magnetic field (∼200 G). The standing waves are measured and compared using a two-dimensional wave calculation.