Ion Bombardment Secondaty Electron Maintenance of Steady RF Discharge

The results of both theoretical and experimental study of a steady E-type RF discharge, in which ionization is controlled by fast electrons generated in RF sheaths near the electrodes (y regime), are presented. It is shown that the transition of an RF discharge into the ? regime is of a threshold nature and is accompanied by a sharp increase in plasma density and a decrease in electron temperature. The suggested theoretical model of an RF discharge in the ? regime satisfactorily describes experiments carried out in a wide range of frequencies, RF voltages, and gas pressures.