HIGH PRECISION EDGE RING CENTERING FOR SUBSTRATE PROCESSING SYSTEMS

An edge ring centering system for a plasma processing system includes a processing chamber including a substrate support and R edge ring lift pins, where R is an integer greater than or equal to 3. An edge ring includes P grooves located on a bottom surface thereof, where P is an integer greater than or equal to R. A robot arm includes an end effector. A controller is configured to cause the optical sensor to sense a first position of the edge ring on the end effector; cause the robot arm to deliver the edge ring to a first center location on the edge ring lift pins; retrieve the edge ring from the edge ring lift pins; and cause the optical sensor to sense a second position of the edge ring on the end effector.