Diagnostics of argon inductively coupled plasma and dielectric barrier discharge plasma by optical emission spectroscopy

An experimental setup was built up to carry out radio frequency (RF) inductively coupled plasma (ICP) and dielectric barrier discharge (DBD), and to depict the optical emission spectra (OES) of the discharges. OES from argon ICP and DBD plasmas in visible and near ultraviolet region were measured. For argon ICP, the higher RF power input (higher than 500 W for authors' machine), the higher degree of argon plasma ionization. But that does not mean a higher mean electron energy. With the increasing in the power input, the mean electron energy increases slightly, whereas the density of electron increases apparently. On the contrary, argon DBD discharge behaves in the manner of a pulsed DC discharge on optical emission spectroscopy and V-I characteristics. DBD current is composed of a series of pulses equally spaced in temporal domain. The kinetics of DBD emission strength is mainly governed by the frequency of the current pulse