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 being carried out by inductive coupling. The operating principle is very similar to that of induction heating of metals . However, the "load," i.e., the conductive plasma, has a significantly lower electrical conductivity than most metals (see table 1 ). This has a direct influence on the optimal frequency, reactor size, and minimum power required to maintain a stable discharge.

The classical theory of induction heating indicates that eddy currents will flow in a cylindrical tube with external radius r _n ...