In this review paper, we discuss the current status of the physics of charged particle swarms, mainly electrons, having plasma modelling in mind. The measurements of the swarm coefficients and the availability of the data are briefly discussed. We try to give a summary of the past ten years and cite the main reviews and databases, which store the majority of the earlier work. The need for reinitiating the swarm experiments and where and how those would be useful is pointed out. We also add some guidance on how to find information on ions and fast neutrals. Most space is devoted to interpretation of transport data, analysis of kinetic phenomena, and accuracy of calculation and proper use of transport data in plasma models. We have tried to show which aspects of kinetic theory developed for swarm physics and which segments of data would be important for further improvement of plasma models. Finally, several examples are given where actual models are mostly based on the physics of swarms and those include Townsend discharges, afterglows, breakdown and some atmospheric phenomena. Finally we stress that, while complex, some of the results from the kinetic theory of swarms and the related phenomenology must be used either to test the plasma models or even to bring in new physics or higher accuracy and reliability to the models.

In this review we discuss the current status of the physics of charged particle swarms, mainly electrons. The whole field is analysed mainly through its relationship to plasma modelling and illustrated by some recent examples developed mainly by our group. The measurements of the swarm coefficients and the availability of the data are briefly discussed. More time is devoted to the development of complete electron-molecule cross section sets along with recent examples such as NO, CF 4 and HBr. We extend the discussion to the availability of ion and fast neutral data and how swarm experiments may serve to provide new data. As a point where new insight into the kinetics of charge particle transport is provided, the role of kinetic phenomena is discussed and recent examples are listed. We focus here on giving two examples on how non-conservative processes make dramatic effects in transport, the negative absolute mobility and the negative differential conductivity for positrons in argon. Finally we discuss the applicability of swarm data in plasma modelling and the relationship to other fields where swarm experiments and analysis make significant contributions.

Electron kinetics determines the rate of production of chemically active species in processing plasmas. Precise transport coefficients are needed to describe conditions such as those found in plasma assisted technologies for semiconductor production, but these are affected by the density of free radicals, which in themselves depend on the chemical kinetics. We present transport coefficients for electrons in mixtures of CF 4 with CF 2 (and we also show similar results for other radicals) for ratios of the electric field to the gas number density E/N from 1 to 1000 Td (1 Td = 10 −21 V m 2 ). Our analysis of non-conservative collisions revealed a range of E/N where electron attachment to radicals significantly changes the electron kinetics compared with pure CF 4 gas. The results are obtained using simple solutions for Boltzmann's equation and exact Monte Carlo simulations.

In this paper we show predictions for the low-energy cross-sections and transport properties for the F − in Ar/BF3 mixtures which does not exist in the literature. These data are needed for modelling in numerous applications of technologically important Ar/BF3 discharges. Results for transport coefficients as a function of E/N (E is the electric field, N the gas density) were obtained by using the Monte Carlo technique. The Monte Carlo method is applied to obtain swarm parameters at the temperature T = 300 K.

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