Studies about Flow Rate Effect on Atomic Fluorine Generation in Inductively Coupled CF4 Plasmas: A Global Model Investigation

Abstract

A volume-averaged global model for inductively coupled carbon tetrafluoride (CF4) plasma was used to study the role of the different processes of production and loss of atomic fluorine on the two different ways to vary the gas pressure: under variable or constant gas flow rate. The results obtained by plasma modeling confirm the behavior of atomic fluorine density with pressure observed in others studies [1-3] when the gas flow rate effect is considered. It's noticeable that the fluorine atoms are created mainly by dissociative processes and lost by recombination to the reactor walls for both gas flow conditions. The relative reaction rate for dissociative processes presents a similar behavior to the fluorine density with the variation of the gas pressure. We also note that the applied power has an important role in reducing the recombination of atomic fluorine to the walls, but does not affect the flow rate effect.