A comparative study of plasma parameters and gas phase compositions in Cl2 and HCl direct current glow discharges

The investigations of plasma parameters and active particles kinetics in Cl2 and HCl direct current glow discharges (p = 40–300 Pa, jd = 8.5 × 10− 3 A/cm2) were carried out. The investigation combined plasma diagnostics by Langmuir probes, absorption spectroscopy and self-consistent 0-dimensional plasma modeling based on the solution of Boltzmann kinetic equation. It was found that the model provides an outstanding agreement with experiment on the reduced electric field strength (E/N), Cl atom density and the total flux of positive ions and thus, gives an adequate description of basic kinetic effects determining the steady-state plasma parameters and composition. Under the same operating conditions, Cl2 plasma provides higher E/N, mean electron energy, dissociation degree and electronegativity that can be explained by the peculiarities of formation-decay kinetics analyzed in both systems.