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Abstract: Radiofrequency discharges fed with CCl4-Cl2 mixtures have been studied in the pressure range 0.3 to 0.6 torr by means of emission spectroscopic actinometry with Ar, He, and N2 as actinometers. Two different reactors, a parallel plate and a capacitively coupled tubular one, have been utilized for this study to obtain information for a large range of electron energy distributions. Analysis of the experimental results demonstrates the following: the utilization of actinometry and its range of validity, the importance of electron attachment to CClx species during the plasma decomposition process, and the effects of the presence of chlorine and “glowpolymer” in the discharge medium.

A diagnostic study q (energy transfer processes in a He-N2 flowing discharge and afterglow has been performed in a radiofrequency-produced plasma cooled in a liquid nitrogen hath. Optical emission spectroscopy in the visible and infrared spectral range as well as Langrnuir probe diagnostics were used. The vibrational kinetics of CO injected in such an afterglow has been examined. It shows a slow cooling of the electrons in the afterglow regime. The electron kinetics responsible joy CO vibrahonal excitation is turned off when N2 is added to the He discharge, while that for vibrationally excited N2 molecules is turned on. The results are discussed on the basis of previous theorerical calculations and experiments on the He-N2 system.

A fast and simple method for estimating the rotational temperature from the partially resolved (3, 0) band of the first positive system of N2(B3Πg-A3Σu+) has been developed by numerical simulation of tire (3, 0) band profile, polynomial linear least-square fitting, and polynomial interpolation. Tire sensitivity of the proposed method is based on the temperature dependence of the relative population of the 3ΠΩ>) substates. Simple polynomial formulas allow calculation of the rotational temperature in the range of 200–1500 K from the (3, 0) band profile after reading the subband head peak values. This method has been tested on the experimental (3, 0) band emission recorded in N2pulsed rf discharges.