Applied Materials, Inc.
System For Determining Cleaning Process Endpoint

Abstract:

A system for determining when a cleaning process has completed is disclosed. This system relies on an increase in the amount of gas in the processing chamber that occurs when the cleaning is complete. This increase in the amount of gas may be detected in several ways. In one embodiment, a downstream pendulum valve is used to maintain the pressure within the processing chamber at a predetermined value. An increase in the size of the opening in the pendulum valve is indicative of the amount of gas in the system. In another embodiment, a sensor may be used to monitor the pressure within the processing chamber, while the incoming and outgoing flow rates are held constant. An increase in the pressure is indicative of an increase in the amount of gas in the processing chamber. This increase in the amount of gas is used to terminate the cleaning process.