Fundamental comparison between non-equilibrium aspects of ICP and MIP discharges

摘要

A characterization theory is constructed to relate external control parameters to averaged values of internal plasma properties. It is based on a study on the effect of transport fluxes on elementary balances. This theory is used to compare the inductively coupled plasma (ICP) with the TIA ('torche a injection axiale', a microwave plasma) and to predict properties of He plasmas. The theory is validated by means of laser experiments on the ICP and TIA. Thomson (TS), Rayleigh (RyS) and Raman (RnS) scattering are used to get insight into spatially resolved plasma parameters. TS gives the electron number density and temperature, whereas the combination of RyS and RnS provides the densities of (entrained) air molecules and argon atoms (main gas). In particular, the influence of steep gradients and the air entrainment turn out to be of crucial importance for those situations in which the characterization theory does not properly predict the values of plasma parameters.