Kinetics of Ar+*(2G9/2) metastable ions and transport of argon ions in ICP reactor

The decay time of the argon Ar~~(2G912) metastable ions was measured in the afterglow of a low pressure pulsed helicon reactor. From the argon pressure and electron density dependence of this decay time, rate coefficients for quenching of these ions by argon atoms and by plasma electrons have been deduced. The velocity distribution of the metastable Ar~ (2G912) ions in the presheath of an inductively coupled plasma has been obtained by using the Doppler shifted laser induced fluorescence technique. Drift of the ions along the electric field in the presheath is observed and distribution functions of the velocity in both parallel and perpendicular directions, relative to the E-field, are deduced at 5 and 40 mTorr. we show that in high density plasmas the velocity distribution of the inetastable ions is directly related to that of the ground state argon ions.