AVS 61st International Symposium & Exhibition
    Plasma Science and Technology Tuesday Sessions
       Session PS-TuP

Paper PS-TuP30
Anomalous Electron Cross-Field Transport in a Low Pressure Magnetized Plasma For Material Processing Applications

Tuesday, November 11, 2014, 6:30 pm, Room Hall D

Session: Plasma Science and Technology Poster Session
Presenter: Yevgeny Raitses, Princeton Plasma Physics Laboratory
Correspondent: Click to Email
The application of the magnetic field in a low pressure plasma can cause a spatial separation of cold and hot electron groups. This so-called magnetic filter effect is used for many plasma applications, including ion and neutral beam sources, plasma processing of semiconductors and nanomaterials, and plasma thrusters. In spite of successful practical applications, the magnetic filter effect is not well understood. In this work, we explore this effect by characterizing the electron and ion energy distribution functions in a plasma column with crossed electric and magnetic fields. Experimental results revealed a strong dependence of spatial variations of the plasma properties across the magnetic field on the gas pressure. In particular, the results showed the existence of the gas pressure threshold below which the increase of the magnetic field leads to a more uniform profile of the electron temperature. This surprising result is due to anomalously high electron cross-field transport that causes mixing of hot and cold electrons. For xenon and argon gases, this threshold is ~ 1 motrr. At higher gas pressures, a stronger separation of cold and hot electrons, which is favorable for the above applications, was observed.