Helicon ion source for plasma processing

The results of theoretical and experimental investigations of dense plasma source resonantly excited by helicon wave are presented. Driven by a single-loop low-voltage (≂300 V) antenna, a source generates a plasma of density up to 5×1011 cm−3 at gas pressures 0.5–20 mTorr, operates at magnetic fields <100 Gs, and produces low-energy ion fluxes (<60 eV) with current densities up to 7 mA/cm2 and 3.5% nonuniformity within a diameter 10 cm. A high-efficiency helicon source originates in a special kind of ‘‘resonance’’ wave discharge, where a sharp increase of plasma resistance occurs near the helicon wave dispersion branches.