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AssigneeKasper Instruments, Inc.
InventorsKarl-Heinz Johannsmeier, Paul E. Stoft, Tor G. Larsen
Estimating the term…
An apparatus for automatically aligning a semiconductor wafer with a mask in the manufacture of integrated circuit devices is disclosed. The mask and wafer are each provided with alignment patterns, the alignment pattern on the wafer cooperating with the alignment pattern on the mask in a unique visual manner to signify alignment. A scanning mechanism is provided for automatically scanning the alignment pattern areas and producing output signals indicative of the relative positions of the alignment patterns on the wafer and mask. Logic circuitry is provided for operating in response to any misalignment represented by the scan output signals to compute formulae which are utilized to produce control signals for driving motor drive mechanisms to produce relative movement between the mask and wafer to bring them into alignment. Several separate alignment cycles are provided, if needed, for zeroing in on finalized alignment. A tolerance selection control circuit is provided for permitting a variation in final alignment tolerance.
A system for aligning first and second relatively movable objects, where the first object has an alignment pattern thereon, the second object has a corresponding alignment pattern thereon, and the alignment pattern on the first object is disposed in a preselected alignment position relative to the corresponding alignment pattern on the second object when the first and second objects are aligned, said system comprising first means operable for repetitively determining the angular and the coordinate displacement between the alignment pattern on the first object and the preselected alignment position relative to the corresponding alignment pattern on the second object, and second means operable following each such determination by the first means for moving the first object relative to the second object through an angle and a distance based on that determination to incrementally bring the alignment pattern on the first object into the preselected alignment position relative to the corresponding alignment pattern on the second object.
A system for aligning first and second relatively movable objects, where the first object has a pattern thereon, the second object has a corresponding pattern thereon, and the pattern on the first object is disposed in a preselected position relative to the corresponding pattern on the second object when the first and second objects are aligned, said system comprising first means operable for repetitively determining the angular and the coordinate displacement between the pattern on the first object and the preselected position relative to the corresponding pattern on the second object, and second means operable following each such determination by the first means for moving the first object relative to the second object through an angle and a distance based on that determination to incrementally bring the pattern on the first object into the preselected position relative to the corresponding pattern on the second object.
Dependencies are inferred from the claim text.