Patent ID: 6843704
Filing Date: 2005-01-18
Classification: B24B,H01L

Abstract:
1. A method for automatically transferring wafer crystals with respect to a double-sided polishing machine of the type having an upper and a lower polishing plate, and runner disks resting on the lower polishing plate the runner disks having individual reception openings in the runner disks for the wafer crystals, and a controlled drive for moving the individual runner disks to a predetermined loading and unloading position, the method characterized by: a) measuring and storing a position of each center of the respective reception openings in a runner disk located at a loading position using a first optical identification system; b) successively orienting a gripping means of a loading arm of a robot without a wafer towards the measured center position of each of the reception openings; c) determining and storing a more precise position of each of the centers of the respective individual reception openings using a second optical identification system mounted on the arm during the successive orientation of the gripping means; and d) inserting individual wafer crystals into respective reception openings of the runner disk in a predetermined sequence using the gripping means of the loading arm using the stored more precise positions.