Modelling of reactors for plasma processing I. Silicon etching by CF₄ in a radial flow reactor

Modelling of glow discharge (plasma) processes is illustrated by the formulation of a reaction engineering model for a radial flow, parallel plate plasma reactor. Features of the discharge structure are described along with a brief discussion of the modelling necessary to predict ion concentrations, electron density and energy. In the present case, electron density and energy are included as parameters in the reactor continuity balances. The industrially important etching of silicon in CF₄ is used as an example. The modeling equations are solved by finite element methods and the model predictions are used to demonstrate the influence of operating parameters on etch rate magnitude and uniformity.