Stabilization and control of a high-pressure glow discharge by means of a m
icrohollow cathode discharge has been demonstrated. The microhollow cathode
discharge, which is sustained between two closely spaced electrodes with o
penings of approximately 100 mu m diam, serves as plasma cathode for the hi
gh-pressure glow. Small variations in the microhollow cathode discharge vol
tage generate large variations in the microhollow cathode discharge current
and consequently in the glow discharge current. In this mode of operation
the electrical characteristic of this system of coupled discharges resemble
s that of a vacuum triode. Using the microhollow cathode discharge as plasm
a cathode it was possible to generate stable, direct current discharges in
argon up to atmospheric pressure, with estimated electron densities in the
range from 10(11) to 10(12) cm(-3). The recently demonstrated parallel oper
ation of these discharges indicates the potential of this technique for the
generation of large volume plasmas at high gas pressure through superposit
ion of individual glow discharges. (C) 1999 American Institute of Physics.
[S0021-8979(99)07304-1].