Vibrational Temperature Estimation of Nitrogen Molecules in Radio-Frequency (RF) Produced Plasma

A capacitive coupled radio frequency (RF) plasma system has been developed for producing tungsten coated graphite tiles using assisted chemical vapor deposition (PACVD) technique. To characterize the chamber optimal parameters, small amount of air is released into hydrogen purposefully to measure its gas temperature spectral bands nitrogen molecule. Optical emission spectra in wavelength range 350 900 nm have recorded with a miniature spectrometer. Molecular N2 (B3Πg-A3 Σu+ ) observed and identified as three from 1PS (Δν = 2, 3 & 4). These are simulated MATLAB code in-house by considering Boltzmann distribution particles vibrational states. The experimental modelled spectrum through best-fit technique iterating latter one different values. plot method also utilized evaluate bands. estimated modelling matches fairly well method. temperatures ∼7000 - 8000 K, an order higher than room ∼300 K.