Characterization of an asymmetric DBD plasma jet source at atmospheric pressure

Non-thermal atmospheric pressure plasma jets or plasma plumes have recently been largely investigated in applications like materials processing, biomedical treatment and analytical chemistry. In this paper He-discharges in an asymmetrical Dielectric Barrier Discharge (DBD) have been experimentally studied with an Intensified Charge Coupled Device (ICCD) camera, Optical Emission Spectroscopy (OES) and Time-Of-Flight Mass Spectrometry (TOF-MS) measurements. The development of the plasma plume, its apparent length and the spatial distribution of the excited and ionized species along the plasma plume have been characterized as a function of the applied voltage and the gas flow rate. A TOF-MS spectrometer has been used to characterize ionized species (positive and negative ions) produced by the plasma alone and the plasma with addition of ethanol, both as a function of the distance between the plasma plume and the vacuum interface of the spectrometer.