OICC Press Journal of Theoretical and Applied Physics 2251-7235 6 1 2023 11 17 Characterization of argon/air atmospheric pressure capacitively coupled radio frequency dielectric barrier discharge regarding parasitic capacitor at 13.56 MHz 10.1186/2251-7235-6-32 EN Farshad Sohbatzadeh Department of Atomic and Molecular Physics, Faculty of Basic Sciences, University of Mazandaran, Babolsar, Iran Saeed Mirzanejhad Department of Atomic and Molecular Physics, Science Faculty, University of Mazandaran, Babolsar, Iran Hoda Mahdavi Department of Atomic and Molecular Physics, Science Faculty, University of Mazandaran, Babolsar, Iran Zahra Omidi Department of Atomic and Molecular Physics, Science Faculty, University of Mazandaran, Babolsar, Iran Journal Article 2023 11 17 AbstractIn this paper, uniform argon glow discharge at atmospheric pressure in a diffuse mode driven by a 300-W radio-frequency (13.56 MHz) power supply based on dielectric barrier discharge was investigated. In this work, the effect of the parasitic capacitor on the electrical characteristics of the capacitively coupled atmospheric pressure plasma was investigated. It was revealed that more than half of the RF current is parasitic in our system as a characteristic of the capacitively coupled plasma. It was also proved that the discharge resistance and sheath capacitance increase at higher input powers while the impedance decreases. In order to recognize plasma, optical emission spectroscopy apparatus was used. Argon, oxygen, copper, and nitrogen spectrum lines were diagnosed. The plasma gas temperature and electronic excitation temperature were investigated showing a non-equilibrium discharge.