Low-pressure discharges exist within
Gas-discharge lamp
Gas-discharge lamps are a family of artificial light sources that generate light by sending an electric discharge through an ionized gas, a plasma.
Typically, such lamps use a
noble gas (argon, neon, krypton, and xenon) or a mixture of thes ...
s. The
electric discharges in gases are made under gas pressures from a few
millitorr to a little less than atmospheric.
Description
They are most often used in industry to generate
plasma
Plasma or plasm may refer to:
Science
* Plasma (physics), one of the four fundamental states of matter
* Plasma (mineral), a green translucent silica mineral
* Quark–gluon plasma, a state of matter in quantum chromodynamics
Biology
* Blood pla ...
. Less power is required to sustain the discharge at lower pressures as
volume-recombination rates are lower. It is also easier to achieve uniform discharges at low pressure.
Normally, the system is pumped down and only necessary plasma gases are then flown into the plasma chamber.
Argon
Argon is a chemical element with the symbol Ar and atomic number 18. It is in group 18 of the periodic table and is a noble gas. Argon is the third-most abundant gas in Earth's atmosphere, at 0.934% (9340 ppmv). It is more than twice as abu ...
is a typical background gas because it has low ionization potential and therefore is easier to break down and sustain.
Most discharges used in the
semiconductor industry
The semiconductor industry is the aggregate of companies engaged in the design and fabrication of semiconductors and semiconductor devices, such as transistors and integrated circuits. It formed around 1960, once the fabrication of semiconduct ...
employ low-pressure plasmas.
See also
*
References
Gas discharge lamps
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