| Title |
Ionization and Attachment Coefficients in CF4, CH4, Ar Mixtures Gas |
| DOI |
https://doi.org/10.5370/KIEEP.2012.61.1.013 |
| Keywords |
Drift velocities ; Monte Carlo simulation(MCS) ; Boltzmann equation(BEq) |
| Abstract |
Ionization and Attachment Coefficients in pure CH_4, CF_4 and mixtures of CF_4 and Ar, have been analyzed over a range of the reduced electric field strength between 0.1 and 350[Td] by the two-term approximation of the Boltzmann equation (BEq.) method and the Monte Carlo simulation (MCS). The calculations of electron swarm parameters require the knowledge of several collision cross-sections of electron beam. Thus, published momentum transfer, ionization, vibration, attachment, electronic excitation, and dissociation cross-sections of electrons for CH_4, CF_4 and Ar, were used. The results of the Boltzmann equation and the Monte Carlo simulation have been compared with the data presented by several workers. The deduced transport coefficients for electrons agree reasonably well with the experimental and simulation data obtained by Nakamura and Hayashi. The energy distribution function of electrons in CF_4-Ar mixtures shows the Maxwellian distribution for energy. That is, f({\varepsilon}) has the symmetrical shape whose axis of symmetry is a most probably energy. The proposed theoretical simulation techniques in this work will be useful to predict the fundamental process of charged particles and the breakdown properties of gas mixtures. |