Method and apparatus for safely dechucking wafers

摘要

A wafer stage installed in a process chamber for safely dechucking a wafer is provided. In one embodiment, the wafer stage comprises: a chuck support for supporting a chuck; a chuck mounted on the chuck support for receiving and attaching a wafer thereto; a support lift means for supporting the wafer; a driving means coupled to the support lift means for gradually raising the support lift means to contact the wafer in response to a variable quantity; a sensor attached to the driving means for detecting a change in the variable quantity; and a controller for controlling the variable quantity to the driving means when a predetermined variable quantity is detected in comparison to the change in the variable quantity for a predetermined time.