Infrared absorption spectroscopy has been used to measure the absolute
densities of neutral particles in various fluorocarbon RF plasmas. Th
e densities of CF2 radicals have been measured using a tunable diode l
aser. Moreover, broadband absorption spectra obtained using a Fourier
transform spectrometer have been used to determine the densities of st
able reaction products and to assess the degree of dissociation in the
plasma. The results indicate that the rotational temperatures of all
species involved are slightly above room temperature. The density of C
F2 at high gas pressures increases close to the electrodes, indicating
production near or on the electrodes and loss in the gas phase. The d
issociation degree in plasmas of gases with a high C/F ratio can be as
high as 90%. From an analysis of the flow dependence of the degree of
dissociation the total dissociation rate coefficients of CF4, CF2Cl2,
CF3Cl and C2F4Cl2 have been calculated.