CONTROL SYSTEMS EMPLOYING DEFLECTION SENSORS TO CONTROL CLAMPING FORCES APPLIED BY ELECTROSTATIC CHUCKS, AND RELATED METHODS

摘要

A control system that includes deflection sensors which can control clamping forces applied by electrostatic chucks, and related methods are disclosed. By using a sensor to determine a deflection of a workpiece supported by an electrostatic chuck, a control system may use the deflection measured to control a clamping force applied to the workpiece by the electrostatic chuck. The control system applies a clamping voltage to the electrostatic chuck so that the clamping force reaches and maintains a target clamping force. In this manner, the clamping force may secure the workpiece to the electrostatic chuck to enable manufacturing operations to be performed while preventing workpiece damage resulting from unnecessary higher values of the clamping force.

主权项

1. A control system, comprising:
an electrostatic chuck; an interferometric sensor positioned to determine a deflection of a workpiece into at least one recess of the electrostatic chuck as the electrostatic chuck applies a clamping force to the workpiece; and a controller configured to:
determine a clamping force to apply to the workpiece based on the determined deflection; andadjust a clamping voltage at the electrostatic chuck to apply the clamping force to the workpiece.