US4093378A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alignment apparatus
Assignee: International Business Machines Corp
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Filing: 1976-11-01
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Granted: 1978-06-06
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Expires: 1996-11-01
Abstract
Abstract This describes an apparatus and method especially adapted for positioning a semiconductor wafer in a preferred plane with respect to a photomask so as to achieve improved photolithographic focusing. The apparatus comprises a holder, provided with a surface for receiving a semiconductor wafer thereon, mounted in a chuck which mates with an adaptor ring containing both driver mechanisms and sensors for sensing and positioning the wafer. The sensors define a reference plane and converts the spacing between the reference plane and the front surface of the semiconductor wafer into electrical signals which can be fed to the driver mechanisms to position, with both rotational or translational motion, the plane of the wafer by moving the holder until all the signals from the sensors are nulled. Once the wafer is properly aligned, the sensors continually monitor the position of the wafer and the driver mechanisms continually provide loading to the wafer holder to continually maintain the wafer in its preferred position with respect to the established reference plane.
Inventors
- 👤 Andrew Frederick Horr
- 👤 William Frederick White
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:42
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/70; G03F7/70691; H; H10; H10P; H10P72/00; H10P72/70; H10P72/78
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
98 words
A mechanism for positioning the surface of an object in a selected position with respect to a reference plane comprising: means for holding said object, means for defining said reference plane driver means aligned with said holding means, and sensor means coupled to said driver means and spaced from said object for sensing the the surface of said object with respect to said reference plane and controlling respective ones of said driver means to engage and move the holding means to position the sensed surface of said object in said selected position with respect to said reference plane.
Claim 2
Dependent Claim
98 words
A mechanism for positioning the surface of an object in a selected position with respect to a reference plane comprising: means for holding said object, means for defining said reference plane driver means aligned with said holding means, and sensor means coupled to said driver means and spaced from said object for sensing the the surface of said object with respect to said reference plane and controlling respective ones of said driver means to engage and move the holding means to position the sensed surface of said object in said selected position with respect to said reference plane.
Claim 3
Dependent Claim
128 words
A mechanism for positioning and maintaining the plane surface of a unit in a selected attitude with respect to a reference plane comprising: a unit having a plane surface to be positioned, means for holding said unit, a carrier adapted to mate with said holding means, driver mechanisms on said carrier aligned with said holding means when mated with said carrier, means coupled to said carrier defining said reference plane, and sensors on said carrier being coupled to said driver mechanisms and spaced from said surface of said unit for sensing the position of said surface and controlling said driver mechanisms to engage and move said holding means to position and maintain the sensed surface of the unit in said selected attitude with respect to said reference plane.
Claim 4
Dependent Claim
128 words
A mechanism for positioning and maintaining the plane surface of a unit in a selected attitude with respect to a reference plane comprising: a unit having a plane surface to be positioned, means for holding said unit, a carrier adapted to mate with said holding means, driver mechanisms on said carrier aligned with said holding means when mated with said carrier, means coupled to said carrier defining said reference plane, and sensors on said carrier being coupled to said driver mechanisms and spaced from said surface of said unit for sensing the position of said surface and controlling said driver mechanisms to engage and move said holding means to position and maintain the sensed surface of the unit in said selected attitude with respect to said reference plane.
Claim 5
Dependent Claim
34 words
The mechanism of claim 1 wherein there is further provided an adaptor ring supporting said driver means and said sensor means, said driver means and said sensor means being equally spaced on said ring.
Claim 6
Dependent Claim
31 words
The mechanism of claim 3 wherein said adaptor ring has an inner step, said step being provided with means for securing said means for holding said object in said adaptor ring.
Claim 7
Dependent Claim
24 words
The mechanism of claim 4 wherein said means for holding said object comprises a cup shaped chuck enclosing a spring loaded, moveable mounting means.
Claim 8
Dependent Claim
35 words
The mechanism of claim 5 wherein said mounting means comprises a disc provided with a plurality of radial and circular channels connected to a vacuum source for holding an object having a flat surface thereon.
Claim 9
Dependent Claim
28 words
The mechanism of claim 5 wherein said mounting means is spring loaded by a diaphragm spring that provides translational and rotational freedom of motion to said mounting means.
Claim 10
Dependent Claim
30 words
The mechanism of claim 7 wherein each of said sensor means comprises a dual action air switch which can establish the surface of the object parallel to said reference plane.
Claim 11
Dependent Claim
20 words
The mechanism of claim 8 wherein each of said sensors are coupled to respective driver means through a controller circuit.
Claim 12
Dependent Claim
202 words
A mechanism for positioning the plane surface of a unit in a selected position parallel to a reference plane comprising: a unit having a surface to be positioned, a chuck, a moveable mounting means in said chuck for holding the unit, said moveable mounting means being provided with a plurality of lugs around its periphery, a carrier adapted to mate with the chuck, a plurality of driver mechanisms on said carrier each of which is aligned with a respective one of said lugs on the periphery of said mounting means when the carrier in mated with the chuck, and means on said carrier defining a reference plane, a plurality of sensors being spaced from the surface of the unit when the carrier is mated with the chuck for sensing the position of the surface relative to the reference plane, each sensor being coupled to and controlling respective one of said driver mechanisms to engage and drive the lugs on the mounting means to position and maintain the sensed plane surface of the unit parallel to the reference plane, said moveable mounting means being spring loaded in said chuck providing translational and rotational freedom of movement to said mounting means in said chuck.
Claim 13
Dependent Claim
202 words
A mechanism for positioning the plane surface of a unit in a selected position parallel to a reference plane comprising: a unit having a surface to be positioned, a chuck, a moveable mounting means in said chuck for holding the unit, said moveable mounting means being provided with a plurality of lugs around its periphery, a carrier adapted to mate with the chuck, a plurality of driver mechanisms on said carrier each of which is aligned with a respective one of said lugs on the periphery of said mounting means when the carrier in mated with the chuck, and means on said carrier defining a reference plane, a plurality of sensors being spaced from the surface of the unit when the carrier is mated with the chuck for sensing the position of the surface relative to the reference plane, each sensor being coupled to and controlling respective one of said driver mechanisms to engage and drive the lugs on the mounting means to position and maintain the sensed plane surface of the unit parallel to the reference plane, said moveable mounting means being spring loaded in said chuck providing translational and rotational freedom of movement to said mounting means in said chuck.
Claim 14
Dependent Claim
110 words
In a photoalignment tool a wafer positioner for positioning a wafer in a predetermined plane comprising: an adaptor ring supporting spaced driver mechanisms and sensor units, a chuck housing mated with said adaptor ring, and means having translational and rotational freedom of movement mounted in said chuck housing, for holding a wafer adjacent to said sensor units, said sensor units detecting the distance between the wafer surface and the adaptor ring, said sensors being coupled to said driver mechanisms to control the driver mechanisms to engage and drive the means mounted in said housing to position and maintain the wafer in a selected plane with respect to the adaptor ring.
Claim 15
Dependent Claim
110 words
In a photoalignment tool a wafer positioner for positioning a wafer in a predetermined plane comprising: an adaptor ring supporting spaced driver mechanisms and sensor units, a chuck housing mated with said adaptor ring, and means having translational and rotational freedom of movement mounted in said chuck housing, for holding a wafer adjacent to said sensor units, said sensor units detecting the distance between the wafer surface and the adaptor ring, said sensors being coupled to said driver mechanisms to control the driver mechanisms to engage and drive the means mounted in said housing to position and maintain the wafer in a selected plane with respect to the adaptor ring.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-06-05 | 1981-12-05 | 1982-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-06-05 | 1985-12-05 | 1986-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-06-05 | 1989-12-05 | 1990-06-06 | $7700.00 | Window Closed / Lapsed |