Method and apparatus for handling wafers

摘要

Method for handling disk type objects (10), especially semiconductor wafers, whereby the relative position of a wafer relative to its gripper (1) is first determined. To this end the wafer is rotated within the gripper and the position of its edge scanned using an optical sensor. The scanned data are used to determine the center of the wafer relative to the center of the gripper and if necessary the position of the flat. The determined data is used in subsequent positioning of the wafer in its gripper by a robot. The invention also relates to a corresponding device.