Electron energy distribution functions and power transfer data for radio-frequency discharges in CO2 laser gas mixtures

Abstract

The electron energy distribution function (EEDF) for an RF discharge in a typical CO2 laser gas mixture was calculated by solving the time-dependent Boltzmann equation. The results were used to evaluate power transfer data to the electron system and subsequently to the different degrees of freedom of the gas mixture. In particular the authors investigated the dependence of the EEDF on the RF field frequency for specific field amplitudes EO/N up to 10-15 V cm2. A comparison has been made with the results based on a quasistationary treatment (low frequency limit) and on the stationary solution of the Boltzmann equation assuming a constant specific field. The latter case models a DC discharge as well as an RF discharge in the high-frequency limit, reading the specific field as an effective value of the RF field.