US Patent 11171030 Methods and apparatus for dechucking wafers

Methods and apparatus for dechucking a wafer from a surface of an electrostatic chuck (ESC). In some embodiments, a method comprises reducing a pressure of a gas applied to a backside of the wafer to approximately zero psi; reducing a downward pressure in a cylinder bore of a lifting actuator to approximately atmospheric pressure while a processing volume of the processing chamber is in a vacuum state to create a constant upward force on the wafer, the constant upward force less than a breaking force of the wafer; and sweeping a voltage applied to the ESC to dechuck the wafer; and monitoring a sensor on the lifting actuator that is interposed between a chucking position of the lifting actuator and a transfer position of the lifting actuator to detect when the wafer is dechucked.