Plasma source based on ring-shaped anode layer thruster for a bipolar electron-optical system

The conceptual design of pulsed plasma source for plasma-optic application and materials modification are investigated. The source is based on plasma thruster's technology, that were developed by Goncharov's group in Institute of Physics (Kiev, Ukraine). The plasma device with its two modified closed-drift anode layer thrusters can operate in low-current high-voltage mode and in high-current plasma mode. Most attention in the paper is focused on the latter mode being similar to a glow discharge with a positive column. The study shows that under certain conditions, the discharge with closed electron drift can be accompanied by non-self-sustained hollow-cathode discharges with oscillating electrons which greatly decrease the auxiliary discharge voltage. Presented in the paper the current-voltage characteristics of this type of high-current discharge and the spatial distributions of plasma parameters are measured in the discharge region with double Langmuir probe techniques. The maximum plasma densities on the central cathode axis are (6.5 divided by 6.8)x10(12) cm(-3).