Study of an asymmetric capacitive discharge in oxygen with global model and langmuir probe

Resumo

In this work an oxygen asymmetric capacitive radio frequency discharge was investigated with numerical global model and Langmuir Probe to evaluate the behavior of the electron density (ne) and the electron temperature (Te) as a function of input power and gas pressure. The experimental Langmuir probe measurements show that Te increases for pressures below 30 mTorr, which corresponds to low ne, as usual for Reactive Ion Etching type reactor. Moreover, the experimental and simulated electron temperature are in good agreement for gas pressure values above 25 mTorr, because in this case the electron energy distribution function (EEDF) is Maxwellian, according to assumption made in the global model, for the rate coefficient calculation. For electron density the discrepancy is higher for all pressure range, probably because the effect of secondary electron emission that is not considered in our global model simulations. © The Electrochemical Society.