Effect of electron extraction from a grid plasma cathode on the generation of emission plasma

International Congress on Energy Fluxes and Radiation Effects

Devyatkov, V.N.^1 ; Koval, N.N.^1,2

Institute of High Current Electronics SB RAS, 2/3 Akademichesky Ave., Tomsk

634055, Russia^1

National Research Tomsk State University, 36 Lenin Ave., Tomsk

634050, Russia^2

关键词: Accelerating voltages;    Discharge power supply;    Electron extraction;    Grid stabilizations;    High voltage power supply;    Longitudinal magnetic fields;    Plasma electron sources;    Semiconductor element;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/552/1/012014/pdf
DOI  :  10.1088/1742-6596/552/1/012014

来源: IOP

【 摘 要 】

The paper describes the operating mode of a plasma electron source based on a low- pressure arc discharge with grid stabilization of the plasma emission boundary which provides a considerable (up to twofold) increase in discharge and beam currents at an Ar pressure in the vacuum chamber p 0.02-0.05 Pa, accelerating voltages of up to U 10 kV, and longitudinal magnetic field of up to Bz0.1 T. The discharge and beam currents are increased on electron extraction from the emission plasma through meshes of a fine metal grid due to the energy of a high-voltage power supply which ensures electron emission and acceleration. The electron emission from the plasma cathode and arrival of ions from the acceleration gap in the discharge changes the discharge plasma parameters near the emission grid, thus changing the potential of the emission grid electrode with respect to the discharge cathode. The load is not typical and changes the voltage polarity of the electrode gap connected to the discharge power supply, which is to be taken into account in its calculation and design. The effect of electron emission from the plasma cathode on the discharge system can not only change the discharge and beam current pulse shapes but can also lead to a breakdown of the acceleration gap and failure of semiconductor elements in the discharge power supply unit.