Two-stage sealing system for thermally conductive chuck

摘要

A chuck (36) having two distinct portions mounts a substrate (64) within a vacuum processing chamber. A first sealing stage (92) confines a gas within a heat-transfer interface (72) between one portion of the chuck (36) and the substrate (64). A second sealing stage (98) collects gas escaping from the heat-transfer interface (72) within an intermediate space bounded by the two portions of the chuck (36) and the substrate (64). Pressure in the intermediate space is reduced with respect to pressure at the heat-transfer interface (72) to inhibit leakage of gas from the heat-transfer interface (72) into the vacuum processing chamber.