Reactive Gas Species Characterization of Diffused Atmospheric Pressure Cold Plasma System

Atmospheric pressure cold (non-thermal) plasmas have become increasinglyprevalent within many research and industrial applications due to their rangeof reactive gas species produced. In addition the atmospheric plasma systemsdo not require expensive vacuum systems for their operation and generate awide range of reactive ion species concentration. This experimental researchis being carried out to characterize and quantify the concentrations of thereactive ion species and other residual gases and theoretically extrapolate toradial and axial distances. The diffused atmospheric pressure cold plasmasystem is a capacitive coupled radiofrequency (RF) powered helium-oxygendischarge plasma with relatively low plasma temperatures (few degreesabove room temperature) at 3-5 mm away from the plasma source tip. Inthis system helium is the primary gas with fixed RF powers range from 60W to 180 W. Through proportionally increasing oxygen gas flow rate andapplied RF power the amount of reactive ionized species are quantify andcharacterized. The experiment is also extended to various axial distances andmeasured the decay of the reactive ion species which provides the requiredsurface treatment distances based on the application treatment requirements.Such concentrations and distance threshold data are critical for effectiveunderstanding of the reactive environment produced by the plasma system.Plasma production trials conducted also include base (no auxiliary helium oroxygen used) atmosphere conditions used to test electrical conductivity ofvarious ceramic material. Plasma application revealed electrical properties ofthe ceramics used. Spectroscopy tests allowed for elemental characterizationof the ceramics as well. These experimental systems and data collected canbe effectively used in various applications including surface processing,biomedical applications, material science analysis etc.