Argon Ion and Neutral Metastable Levels Destruction in a Magnetically Enhanced Inductively Coupled Plasma Reactor

This paper deals with pure argon plasma studied in a magnetically enhanced inductively coupled reactor.Laser induced fluorescence technique was performed with an optical parametric oscillator laser on the 3d 4 F 7/2 and 3d 2 G 9/2 Ar+ metastable levels and on the (2P 3/2 0 )4s 2 neutral metastable state to determine their relative densities.Langmuir probe was used as a complementary diagnostic to measure the electron energy distribution functions.When increasing the confinement magnetic field, the metastable state density collapses for all cited levels, by contrast with n e which is continuously growing.Calculations were carried out for neutral argon to explain this behaviour.The results show that the metastable population is depleted by electron-impact excitation and ionization, these loss processes becoming dominant compared to the metastable state creation term.