Transport coefficients and scattering cross-sections for plasma modelling in CF4-Ar mixtures: a swarm analysis

Electron transport coefficients and the excitation, attachment and ionization rates in pure CF4 and in CF4-Ar mixtures have been calculated for a set of cross-sections which was based on the work of Nakamura (1991 Gaseous Electronics and Their Applications ed R W Crompton et al (Tokyo: KTK Scientific) pp 178-200) but which was modified to include more complex dissociation and ionization kinetics required to develop an adequate plasma chemical model. The procedure for the calculation was the direct numerical procedure (DNP) solution to the Boltzmann equation which makes no approximations in the number of terms used to represent the anisotropy of the distribution function in the velocity space. However, its accuracy may be limited by the density of the grid used. In this paper, we apply the DNP technique to establish its adequacy for plasma modelling in pure CF4 and in 5% CF4-Ar mixture, as well as establishing the adequacy of the cross-section set that was used.

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