Atmospheric Pressure DC Plasma Microdischarges: A Characterization Study

Atmospheric pressure dc plasma microdischarges were generated between a thin cylindrical electrode and a flat surface. The glow discharges were characterized both experimentally and numerically. As the applied voltage is increased, the plasma potential in the plasma microdischarge remains constant while the plasma current increases proportionally. For the types of electrode materials and the range of the electrode diameters considered, the current-voltage characteristics of the plasma microdischarge are almost independent of the electrode material and the diameter of the electrodes. Predictions from a numerical model of the argon microdischarge compare favorably with the experimental measurements and the visualization studies. The atmospheric pressure plasma microdischarge can be used for deposition of thin films and for microfabrication.