Optical characteristics of a RF DBD plasma jet in various Ar / O 2 mixtures

• Published in: Pramāṇa 2018-02, Vol.90 (2), p.1-11
• Main Authors: Falahat, A, Ganjovi, A, Taraz, M, Rostami Ravari, M N, Shahedi, A
• Format: Article
• Language: English
• Subjects: Argon; Atomic oxygen; Electron density; Emission analysis; Excitation; Optical emission spectroscopy; Optical properties; Plasma; Plasma jets; Radio frequency; Spectrum analysis
• ISSN: 0304-4289; 0973-7111
• DOI: 10.1007/s12043-018-1520-6

In this paper, using the optical emission spectroscopy (OES) technique, the optical characteristics of a radiofrequency (RF) plasma jet are examined. The Ar/O2 mixture is taken as the operational gas and, the Ar percentage in the Ar/O2 mixture is varied from 70% to 95%. Using the optical emission spectrum analysis of the RF plasma jet, the excitation temperature is determined based on the Boltzmann plot method. The electron density in the plasma medium of the RF plasma jet is obtained by the Stark broadening of the hydrogen Balmer Hβ. It is mostly seen that, the radiation intensity of Ar 4p→4s transitions at higher argon contributions in Ar/O2 mixture is higher. It is found that, at higher Ar percentages, the emission intensities from atomic oxygen (O) are higher and, the line intensities from the argon atoms and ions including O atoms linearly increase. It is observed that the quenching of Ar∗ with O2 results in higher O species with respect to O2 molecules. In addition, at higher percentages of Ar in the Ar/O2 mixture, while the excitation temperature is decreased, the electron density is increased.