Wafer center finding with charge-coupled devices

• Main Authors: KILEY CHRISTOPHER C, FOGEL PAUL E, VAN DER MEULEN PETER, BUZAN FORREST T
• Format: Patent
• Language: English
• Published: 28.08.2012
• Subjects: BASIC ELECTRIC ELEMENTS; CONVEYING; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; HANDLING THIN OR FILAMENTARY MATERIAL; MEASURING; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS; MEASURING LENGTH, THICKNESS OR SIMILAR LINEARDIMENSIONS; PACKING; PERFORMING OPERATIONS; PHYSICS; PNEUMATIC TUBE CONVEYORS; SEMICONDUCTOR DEVICES; SHOP CONVEYOR SYSTEMS; STORING; TECHNICAL SUBJECTS COVERED BY FORMER USPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ARTCOLLECTIONS [XRACs] AND DIGESTS; TESTING; TRANSPORT OR STORAGE DEVICES, e.g. CONVEYORS FOR LOADING ORTIPPING; TRANSPORTING

A device for handling a substantially circular wafer is provided. The device includes an interior accessible through a plurality of entrances, and a plurality of sensors consisting of two sensors for each one of the plurality of entrances, each sensor capable of detecting a presence of the substantially circular wafer, at a predetermined location within the interior, wherein the plurality of sensors are arranged so that at least two of the plurality of sensors detect the wafer for any position of the wafer entirely within the interior, wherein a first one of the two sensors is positioned to detect the wafer when the wafer has passed entirely into the interior through one of the plurality of entrances, and a second one of the two sensors is positioned immediately outside a diameter of the wafer when the wafer has passed entirely into the interior through one of the plurality of entrances.