Patent ID: 8048226

Claim:
A processing system for treating a substrate, comprising: a process chamber; a substrate holder coupled to said process chamber and configured to support the substrate; a gas distribution system coupled to said process chamber, wherein said gas distribution system is configured to introduce a process gas to a process space above an upper surface of said substrate; and a pumping system coupled to said process chamber and configured to evacuate said process chamber from below said substrate holder such that a flow of the process gas proceeds radially outward along said surface of the substrate holder; a flow modulation element coupled to said substrate holder at a position beyond a peripheral edge of said substrate, wherein said flow modulation element comprises a plurality of gas distribution plenums configured to receive a flow of additive process gas from a plurality of gas distribution passages and distribute the respective flows of additive process gas to corresponding groups of gas injection orifices which are provided at said position beyond said peripheral edge of said substrate and configured to introduce a flow of said additive process gas that proceeds in a direction substantially away from said substrate and having a directional component, in a downstream direction from the substrate such that the flow of additive process gas adjusts the flow of process gas along the substrate proximate the edge of the substrate relative to along the substrate proximate a center of the substrate, and wherein each flow of additive process gas is coupled to each gas distribution passage from separate and distinct gas supply passages provided in the substrate holder.