Patent ID: 6328803
Filing Date: 2001-12-11
Classification: C23C,H01J

Abstract:
A method for controlling a vacuum process for semiconductor wafers comprising:providing a plurality of vacuum process chambers configured to perform the vacuum process, the chambers comprising pressure sensors configured to detect vacuum pressures in the chambers, valves in flow communication with the chambers configured to adjust the vacuum pressures, and controllers in signal communication with the pressure sensors configured to control the valves;determining defects on selected wafers processed in the chambers using the vacuum process;determining an optimal rate of pressure change in the chambers for reducing the defects during the vacuum process;placing the wafers in the chambers and performing the vacuum process;sensing the vacuum pressures in the chambers during the vacuum process using the pressure sensors; andcontrolling the vacuum pressures to reduce the defects by maintaining the optimal rate of pressure change in the chambers during a pump down cycle and a vent up cycle of the vacuum process using the valves and the controllers.