Improvement of plasma uniformity using ZnO-coated dielectric barrier discharge in open air

Abstract

The discharge behavior in atmospheric pressure dielectric barrier discharge using ZnO-coated dielectric layer is examined. ZnO thin film on alumina using rf magnetron sputter causes about a factor of a million higher surface conductivity than bare alumina surface. Experimental result shows that discharge uniformity is improved definitely in the case of ZnO-coated dielectric barrier discharge. Increase of surface conductivity stimulates charges to spread over the dielectric surface widely. These charge spreading enhances the uniformity and the stability of atmospheric pressure discharge in open air by initiation of consecutive streamers.

Plasma expansion of ZnO-coated surface barrier discharge in open air and its optical analysis

“…The deposition condition of ZnO film on alumina was the same as our previous report. 9 We measured the relative peak intensities of the second positive system ͑SPS͒ of nitrogen molecules ͑337.1 nm͒ and first negative system ͑FNS͒ of nitrogen molecular ions ͑391.4 nm͒ generated under the open air. The generation of two kinds of excited species, SPS and FNS, was explained mainly by the following relations:…”

“…9 ZnO thin film with high surface conductivity was deposited on the alumina surface by rf magnetron sputtering. This ZnO-coated DBD stimulates charge accumulation after one discharge pulse.…”

Processing of Open Porous Zirconia via Alkane-Phase Emulsified Suspensions for Plasma Applications

“…The main problems of the usage of DBD in different applications are the homogeneity and the stability of the discharge. Recently, homogeneous and stable discharges at atmospheric pressure, called glow dielectric barrier discharge or APGD have been obtained in helium, argon, or nitrogen 51,52 . The transition from one discharge to the other one does not only depend on the type of gas and the dielectric material but also on the slope of the excitation and the power supply characteristics including their intrinsic imperfections 51 .…”

“…But in the presence of electronegative gases, such as oxygen and water vapor, atmospheric discharges exist as streamer and nonuniform microdischarges (filamentary discharge). Therefore, most of APGDs are generated in other gases, such as He, Ar, and N 2 52 . In these discharges, metastable species of each gas prevent an electron avalanche that induces streamer discharge.…”

“…Recently, homogeneous and stable discharges at atmospheric pressure, called glow dielectric barrier discharge or APGD have been obtained in helium, argon, or nitrogen. 51,52 The transition from one discharge to the other one does not only depend on the type of gas and the dielectric material but also on the slope of the excitation and the power supply characteristics including their intrinsic imperfections. 51 Obtaining uniform and stable discharges in open air is one of the most remarkable achievements in the plasma field research.…”