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The second
floor lab houses the systems we use for plasma processing (deposition
of films, etching/modification of materials, etc.) as well as some
instruments we use for characterizing plasmas and processed samples. 
Most
of the reactors we use for plasma processing are barrel-type inductively-coupled
plasma (ICP) reactors and consist of a nickel-plated copper wire coiled
around a glass barrel.
We use vacuum pumps to maintain high vacuum conditions
(10-3–10-7 Torr)
while flowing a small amount of gas through the reactor. By applying
a radio-frequency (rf) signal to the coil, electrical power is coupled
to the gas in the reactor. This causes the gas to break down into
a complex mixture of ions, electrons, radicals, and excited species. 
The
behavior of this reactive mixture is thus determined by the nature
of the gas that is flowing through the reactor (the feedgas) as well
as the gas pressure and the amount of rf power that is being coupled
to the plasma.
In addition to our ICP reactors, we also have a capacitively-coupled parallel plate plasma reactor. This reactor differs from the others in that the plasma is generated between two disk-shaped electrodes that are situated parallel to each other (like a capacitor) inside a stainless steel chamber. Having the electrodes in direct contact with the plasma creates some different plasma properties, but one of the advantages of using this reactor is that it can be used to study plasma etching without affecting the stainless steel reactor walls. This might not be the case with our other reactors, where samples might be contaminated by material etched from the glass reactor walls.