Patent attributes
A vacuum valve assembly for use in a vacuum processing chamber includes a seat defining an opening in the vacuum valve, with the seat having a sealing face adjacent the opening and normal to the direction of the opening; and a gate having a sealing face adapted to mate with the seat sealing face, the gate being movable toward and away from the seat sealing face to seal and open the vacuum valve opening. A continuous elastomeric seal extends around the vacuum valve opening between the gate sealing face and the seat sealing face of sufficient size such that when the gate is positioned to seal the vacuum valve opening, there exists a gap between the gate sealing face and the seat sealing face. A purge gas port system, disposed in the seat or in the gate, has an inlet for a purge gas, an essentially continuous outlet extending around the vacuum valve opening and adjacent the elastomeric seal and gap, and a manifold system connecting the inlet and the outlet. When a purge gas is introduced through the inlet, the manifold distributes the gas to the outlet which evenly distributes the gas to the vicinity of the continuous elastomeric seal around the vacuum valve opening in the gap between the gate sealing face and the seat sealing face.
