Spectroscopic characterization of an atmospheric pressure mu-jet plasma source
Nikita Bibinov, N Knake, H Bahre, Peter Awakowicz, Volker Schultz-von der Gathen
JOURNAL OF PHYSICS D-APPLIED PHYSICS, Volume: 44, Issue: 34, Article Number: 345204, DOI: 10.1088/0022-3727/44/34/345204, Published: AUG 31 2011
A new method for determination of plasma parameters under atmospheric pressure conditions is formulated and applied for characterization of a radio-frequency mu-jet plasma source using He/O(2) mixture. By applying absolutely calibrated optical emission spectroscopy and numerical simulation, the gas temperature in the active plasma region and plasma parameters (electron density and electron distribution function) are determined. The steady-state concentrations of different species such as oxygen atom and ozone in the plasma channel and in the effluent of the plasma source are calculated using measured plasma parameters and gas temperature. On the other hand, spatial distribution of steady-state densities of these species are measured using emission and absorption spectroscopy. A comparison of the results thus obtained and the validation of the new method against two-photon absorption laser-induced fluorescence spectroscopy measurements are discussed. In addition, the influence of the surface processes and gas flow regime on the loss of the active species in the plasma source are discussed.