A gas flow uniformity study in large-area showerhead reactors for RF plasma deposition

A simple one-dimensional model for plasma deposition in a rectangular showe rhead reactor with single side pumping has been developed in order to expla in the mechanisms which yield uniform deposition using this gas flow config uration. Although the flow velocity increases linearly with distance toward s the pumping side, the solution of the transport equations for the neutral species shows that their number densities are constant throughout the reac tor. Consequently, the plasma and surface deposition reactions are independ ent of position in any arbitrarily-large-area showerhead reactor.