Variable vent pressure and flow for flushing loadlock chamber

Abstract

A workpiece processing system has a process chamber for processing a workpiece. A loadlock chamber has a workpiece support to support the workpiece. A vacuum isolation valve permits the workpiece to transfer between the workpiece support and the process environment. An atmospheric isolation valve permits the workpiece to transfer between the workpiece support and an atmospheric environment. A vent gas control device controls a pressure or a flow rate of a vent gas to the loadlock volume. A workpiece location system determines a presence of the workpiece on the workpiece support. The vent gas control device is controlled based on the workpiece being present on the workpiece support, the process time, and the vent time, maximizing the pressure or flow rate of the vent gas when the workpiece is not on the workpiece support, and maximizing conditioning of the loadlock chamber.

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