Method for preventing contamination in a plasma process chamber

Abstract

A method and an apparatus for preventing contamination in a plasma process chamber when the primary heating means for the chamber is turned off is provided. In the method, a heated gas is flown over the top chamber lid of the plasma process chamber. A suitable heated gas can be nitrogen gas that is heated to a temperature between about 100° C and about 150° C. The present invention is further directed to an apparatus of a plasma process chamber that is equipped with a primary heating means and an auxiliary heating means. The auxiliary heating means is turned on as soon as the primary heating means is turned off such that a heated gas is flown onto the top chamber lid, thus preventing contaminating particles from falling off the chamber wall and preventing contamination of a wafer situated inside the chamber.

Dependencies are inferred from the claim text.