Eur. Phys. J. D 10, 449-456 (2000)
https://doi.org/10.1007/s100530050567

Plasma parameters in a multidipole plasma system

Faculty of Physics, "Al. I. Cuza"University, 6600 Iasi, Romania

Received: 10 February 1999
Revised: 1 September 1999
Published online: 15 June 2000

Abstract

Plasma potential and electron number densities and electron temperatures under bi-Maxwellian approximation for electron distribution function of the multidipole argon plasma source system were measured for a gas pressure ranging between 10^-4 and 10^-3 mbar and an anode-cathode voltage ranging between 40 and 120 V but a constant discharge current intensity. The first group, as ultimate or cold electrons and main electron plasma population, results by trapping of the slow electrons produced by ionisation process due to primary-neutral collisions. The trapping process is produced by potential well due to positive plasma potential with respect to the anode so that electron temperature of the ultimate electrons does not depend on both the gas pressure and discharge voltage. The second group, as secondary or hot electrons, results as degrading process of the primaries and their number density increases while their temperature decreases with the increase of both the gas pressure and discharge voltage.