Plasma parameter characterization of a reflex plasma source operating inoxygen

Abstract

A reflex discharge plasma, obtained as a hybrid between a Penning dischargeplasma (PDP) and a hollow-cathode discharge (HCD) plasma, is analysed as apossible direction-current, high-density plasma source. The experiment is run inoxygen at pressures of 10 mTorr and 1 mTorr, and for discharge currents of 100to 200 mA. Although the gas pressure is considerably lower than those used inHCDs, the hollow-cathode effect (HCE) occurs for current levels higher than100 mA and leads to plasma densities comparable with those obtained usinginductive plasma sources. The presence of a constant magnetic field leads to theenhancement of electron emission from cathodes under ion bombardment, and to thedecreasing of the ion loss by diffusion to the wall.