Method and apparatus for directing fluid through a semiconductor

Abstract

A method and apparatus for directing a process gas through a wafer processing apparatus, such as a vapor deposition chamber is provided. The apparatus comprises a pumping plate (4) defining a central opening (62) surrounding the wafer (W) and having an upper surface (64) facing the processing chamber (12) and a opposite, lower surface (66) facing a pumping channel (14). The plate defines a plurality of circumferentially spaced gas holes (90) extending between the first and second surfaces for discharging process gases from the chamber into the pumping channel. The gas holes are essentially straight so that they flow directly through the pumping plate, thereby minimizing the residence time of the gases within the processing chamber and reducing the time required to clean the gas holes. In addition, the gas holes extend in a radially outward direction relative to the central opening to substantially uniformly discharge the gas from the processing chamber. The radial orientation of the gas holes also allows the inlets of the gas holes to be located near the wafer so that the pumping plate can be designed to minimize the volume of the processing chamber.