| abstract |
Apparatus for producing an electric-field plasma is constructed with a hollow, electrically-conductive conduit connected in series with a radio frequency resonant circuit. The spatial relationship of the hollow conduit and the inductance of the resonant circuit is selected to avoid transformer action. The components of the generator (including the plasma) interact to effect a high Q under unloaded conditions and a low Q under loaded conditions. Flowable material, usually including a carrier gas, is displaced through the conduit while RF energy is applied to the resonant circuit. By proper adjustment of the process parameters, the gas may be excited to and maintained at preselected energization levels. Plasmas may be initiated by the application of RF energy alone without auxiliary initiation techniques. Plasmas generated at ambient pressures may optionally be either at close to thermal equilibrium or at substantial thermal nonequilibrium. Plasmas at thermal nonequilibrium may comprise noble gases (or other substances susceptible to excitation to a mestastable state) in a metastable state. |