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Indexed by:期刊论文

Date of Publication:2009-03-01

Journal:CHINESE PHYSICS B

Included Journals:SCIE、EI、ISTIC、Scopus

Volume:18

Issue:3

Page Number:1177-1180

ISSN No.:1674-1056

Key Words:high-voltage nanosecond pulse; PIC-MCC model; EEDF; IEDF

Abstract:This paper reports that a simulation of glow discharge in pure helium gas at the pressure of 1.333 x 10(3) Pa under a high-voltage nanosecond pulse is performed by using a one-dimensional particle-in-cell Monte Carlo collisions (PIC-MCC) model. Numerical modelling results show that the cathode sheath is much thicker than that of anode during the pulse discharge, and that there exists the phenomenon of field reversal at relative high pressures near the end of the pulse, which results from the cumulative positive charges due to their finite mobility during the cathode sheath expansion. Moreover, electron energy distribution function (EEDF) and ion energy distribution function (IEDF) have been also observed. In the early stage of the pulse, a large amount of electrons can be accelerated above the ionization threshold energy. However, in the second half of the pulse, as the field in bulk plasma decreases and thereafter the reverse field forms due to the excessive charges in cathode sheath, although the plasma density grows, the high energy part of EEDF decreases. It concludes that the large volume non-equilibrium plasmas can be obtained with high-voltage nanosecond pulse discharges.