On the extraction of positive and negative ions from electron-beam-generated plasmas

Walton, S. G.; Leonhardt, D.; Fernsler, R. F.; Meger, R. A.
July 2003
Applied Physics Letters;7/28/2003, Vol. 83 Issue 4, p626
Academic Journal
The results of investigations using pulsed, electron-beam-produced plasmas in Ar/SF[sub6] mixtures are reported. Positive and negative ions were extracted during the active phase of plasma production using a low-frequency, low-voltage bias applied to the sampling electrode. Time-averaged energy distributions, accumulated over several extraction periods, were employed to investigate the flux of both the positive and negative ions. The extraction of negative ions in large quantities suggests the formation of ion–ion plasmas, and the time-averaged energy distributions are in agreement with estimates of sheath formation at the biased electrode.


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