A method for automatically calibrating the position of a wafer handling robot relative to a wafer carrier. The method comprises providing a semiconductor processing assembly comprising the wafer carrier and the wafer handling robot having an end effector, placing a wafer on a wafer support surface of the end effector, moving the end effector to an end position adjacent the wafer carrier, determining a displacement of the wafer on the wafer support surface, repeating these steps until the magnitude of the displacement meets a set end criterion, and storing the latest used end position as a calibrated end position.