Gregory R. Nowling

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The α and γ modes of an atmospheric pressure, radio-frequency plasma have been investigated. The plasma source consisted of two parallel electrodes that were fed with helium and 0.4 vol% nitrogen. The transition from α to γ was accompanied by a 40% drop in voltage, a 12% decrease in current and a surge in power density from 25 to 2083 W cm−3. Optical(More)
The physics of helium and argon rf discharges have been investigated in the pressure range from 50 to 760 Torr. The plasma source consists of metal electrodes that are perforated to allow the gas to flow through them. Current and voltage plots were obtained at different purity levels and it was found that trace impurities do not affect the shape of the(More)
Silicon nitride films were deposited using an atmospheric pressure plasma source. The discharge was produced by flowing nitrogen and helium through two perforated metal electrodes that were driven by 13.56 MHz radio frequency power. Deposition occurred by mixing the plasma effluent with silane and directing the flow onto a rotating silicon wafer heated to(More)
Surface graft polymerization of 1-vinyl-2-pyrrolidone onto a silicon surface was accomplished by atmospheric pressure (AP) hydrogen plasma surface activation followed by graft polymerization in both N-methyl-2-pyrrolidone (NMP) and in an NMP/water solvent mixture. The formation of initiation sites was controlled by the plasma exposure period, radio(More)
A chamberless, remote plasma deposition process has been used to coat silicon and plastic substrates with glass at ambient conditions. The films were deposited by introducing an organosilane precursor into the afterglow of an atmospheric plasma fed with helium and 2 vol% oxygen. The precursors examined were hexamethyldisilazane, hexamethyldisiloxane,(More)
The properties of electronegative discharges operating at atmospheric pressure have been investigated. The plasma source consisted of two parallel metal electrodes into which helium was fed with 0.5–8.0 Torr carbon tetrafluoride or sulfur hexafluoride. It was found that the ionization mechanism changed from the αto the γ -mode at a critical RF power level.(More)
The physics of an atmospheric pressure, radio frequency plasma has been investigated. The discharge is generated with helium and 0.4 vol.% nitrogen passing between two metal electrodes with a 3.0-mm gap. It was discovered that at a critical power density of 2.1 kW/cm, the plasma undergoes sheath breakdown and transitions from the to the -mode. Photographs(More)
The etching of uranium oxide films was investigated with a non-thermal, atmospheric pressure plasma fed with a mixture of 2.0 kPa carbon tetrafluoride, 880.0 Pa oxygen and 97.2 kPa helium. Etching rates of up to 4.0 lm/min were recorded at a 200 C sample temperature. X-ray photoemission spectroscopy revealed that the etched surface was highly fluorinated,(More)
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