Emission spectroscopy of Ar + H₂ + C₇H₈ plasmas: C₇H₈ flow rate dependence and pressure dependence

We have studied toluene flow rate dependence and pressure dependence of Ar emission intensities at 425.9 nm, 750.4 nm and 811.5 nm for Ar + H₂ + C₇H₈ plasmas. Electron density and the electron impact excitation rate coefficients are nearly the same for Ar(100%) and Ar+H₂(33%) plasmas. Toluene addition leads to a decrease in the high energy electron density, whereas the effective electron temperature and low energy electron density remain almost the same. The effective electron temperature, and Ar metastable density and/or low energy electron density decrease significantly with increasing the total pressure from 0.1 to 5 Torr