2. RF plasmas

2.1 Principles

RF thermal plasmas are characterized by a total absence of electrodes, with energy transfer from the source to the plasma performed by inductive coupling. The operating principle is very similar to that of inductive metal heating . However, the "charge", i.e. the conductive plasma, has a much lower electrical conductivity than most metals (see table 1 ). This has a direct influence on the optimum frequency, reactor size and minimum power required to maintain a stable discharge.

Classical induction heating theory states that eddy currents will flow in a cylindrical tube of outer radius r _n and thickness δ (skin thickness),...