Patent ID: 6845174
Filing Date: 2005-01-18
Classification: G06K

Abstract:
1. An arrangement for the identification of a substrate, in particular a semiconductor wafer, having at least one identification marking that is located in a predefined position with respect to a position mark on the edge zone of the substrate, comprising a turntable for rotating a substrate placed thereon about a rotation axis; an illumination source and a receiving device for evaluating the intensity of the light emerging from the illumination source, the illumination source and receiving device being arranged in such a way that the edge zone of the substrate, upon rotation thereof, influences the light intensity striking the receiving device; a device for reading the identification marking, having a sensing region that senses only a subregion of the substrate placed on the turntable, the position of the sensing region relative to the rotation axis being modifiable; and a calculation device that calculates, from the intensity changes ascertained during the rotation, a manipulated variable for a correction rotation angle about the rotation axis for alignment of the identification marking with respect to the sensing region, and a manipulated variable for a correction motion for changing the position of the sensing region with respect to the rotation axis or with respect to the actual position of the identification marking, and outputs them to a positioning device.