Patent US4680893A successfully refreshed from Google Patents.
US4680893A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for polishing semiconductor wafers
Assignee: NXP USA Inc
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Filing: 1985-09-23
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Granted: 1987-07-21
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Expires: 2005-09-23
Abstract
Abstract An apparatus for polishing semiconductor material is described in which a movable polishing arm is mounted to a cabinet. Connected to the polishing arm is a workpiece holder or sometimes referred to as a wafer chuck. Adjacent to the polishing arm is a load station which positions the wafer for pick-up by the polishing arm and attached wafer chuck. Mounted to the cabinet, next to a brush station, is a primary polish station which is used to remove the majority of the material. Alongside of the primary polish station is a final polish station used to provide a finished surface to the wafer. The polishing arm discharges the polished wafer into an unload station which is located next to the final polish station.
Inventors
- 👤 Paul W. Cronkhite
- 👤 Bruce C. Bosley
- 👤 James H. Jones
- 👤 Asit G. Patel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 17:28
CPC Classifications
B; B24; B24B; B24B37/00; B24B37/34; B24B37/345; B24B37/04; B24B53/00; B24B53/017; H; H10; H10P; H10P52/00; H10P52/40; H10P52/402
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
166 words
Apparatus for polishing semiconductor wafers having at least first and second turntables and a polishing arm for moving the wafers from one location to another, comprising: a wafer chuck mounted to the polishing arm for picking up a semiconductor wafer, the wafer chuck having capability to dispense water to rinse the wafer before pick up and to use a vacuum to pick up the wafer; a leveling station mounted on the apparatus to assist mounting the wafer chuck in a predetermined orientation; first and second polishing pads mounted on the first and second turntables, respectively, the first polishing pad having a predetermined shape to receive the wafer for primary polishing; and at least one high pressure water jet mounted adjacent the turntables to clean the polishing pads after a polishing operation wherein the wafer chuck is mounted on a shaft which is at a small angle from perpendicular to the turntables and the leveling station serves to assist mounting the wafer chuck perpendicular to the shaft.
Claim 2
Dependent Claim
166 words
Apparatus for polishing semiconductor wafers having at least first and second turntables and a polishing arm for moving the wafers from one location to another, comprising: a wafer chuck mounted to the polishing arm for picking up a semiconductor wafer, the wafer chuck having capability to dispense water to rinse the wafer before pick up and to use a vacuum to pick up the wafer; a leveling station mounted on the apparatus to assist mounting the wafer chuck in a predetermined orientation; first and second polishing pads mounted on the first and second turntables, respectively, the first polishing pad having a predetermined shape to receive the wafer for primary polishing; and at least one high pressure water jet mounted adjacent the turntables to clean the polishing pads after a polishing operation wherein the wafer chuck is mounted on a shaft which is at a small angle from perpendicular to the turntables and the leveling station serves to assist mounting the wafer chuck perpendicular to the shaft.
Claim 3
Dependent Claim
152 words
Apparatus for polishing semiconductor wafers having at least first and second turntables and a polishing arm for moving the wafers from one location to another, comprising: a wafer chuck mounted to the polishing arm for picking up a semiconductor wafer, the wafer chuck having capability to dispense water to rinse the wafer before pick up and to use a vacuum to pick up the wafer; a leveling station mounted on the apparatus to assist mounting the wafer chuck in a predetermined orientation; first and second polishing pads mounted on the first and second turntables, respectively, the first polishing pad having a predetermined shape to receive the wafer for primary polishing; and at least one high pressure water jet mounted adjacent the turntable to clean the polishing pads after a polishing operation, wherein the first polishing pad's predetermined shape is to compensate for flexing of the first turntable during the primary polishing operation.
Claim 4
Dependent Claim
152 words
Apparatus for polishing semiconductor wafers having at least first and second turntables and a polishing arm for moving the wafers from one location to another, comprising: a wafer chuck mounted to the polishing arm for picking up a semiconductor wafer, the wafer chuck having capability to dispense water to rinse the wafer before pick up and to use a vacuum to pick up the wafer; a leveling station mounted on the apparatus to assist mounting the wafer chuck in a predetermined orientation; first and second polishing pads mounted on the first and second turntables, respectively, the first polishing pad having a predetermined shape to receive the wafer for primary polishing; and at least one high pressure water jet mounted adjacent the turntable to clean the polishing pads after a polishing operation, wherein the first polishing pad's predetermined shape is to compensate for flexing of the first turntable during the primary polishing operation.
Claim 5
Independent Claim
188 words
A method for polishing a semiconductor wafer comprising: shaping a primary polishing pad to compensate for flexing of a turntable on which the primary polishing pad is mounted; rinsing the backside of a wafer just prior to picking up the wafer for polishing; picking up the rinsed off wafer with a chuck having a vacuum pick up; placing the wafer on the primary polishing pad; applying a polishing slurry to the primary polishing pad and rotating the polishing pad to polish the wafers; varying by computer control the stoke length and acceleration at the end of each stroke of a control arm holding the chuck to control flatness of the wafer being polished; moving the wafer to a second polishing pad to accomplish final polishing of the wafer; moving the wafer to an unload station so the wafer can be unloaded from the chuck; using a high pressure jet to clean off the polishing pads following the use of each pad by slowly moving a high pressure water jet across the polishing pad; and cleaning the chuck on a brush before picking up another wafer to be polished.
Claim 6
Independent Claim
188 words
A method for polishing a semiconductor wafer comprising: shaping a primary polishing pad to compensate for flexing of a turntable on which the primary polishing pad is mounted; rinsing the backside of a wafer just prior to picking up the wafer for polishing; picking up the rinsed off wafer with a chuck having a vacuum pick up; placing the wafer on the primary polishing pad; applying a polishing slurry to the primary polishing pad and rotating the polishing pad to polish the wafers; varying by computer control the stoke length and acceleration at the end of each stroke of a control arm holding the chuck to control flatness of the wafer being polished; moving the wafer to a second polishing pad to accomplish final polishing of the wafer; moving the wafer to an unload station so the wafer can be unloaded from the chuck; using a high pressure jet to clean off the polishing pads following the use of each pad by slowly moving a high pressure water jet across the polishing pad; and cleaning the chuck on a brush before picking up another wafer to be polished.
Claim 7
Dependent Claim
20 words
The method of claim 3 wherein the shaping of the primary polishing pad is accomplished by using an abrasive chuck.
Claim 8
Dependent Claim
24 words
The method of claim 3 wherein the polishing pads are cleaned by slowly moving the high pressure water jet at 229 mm per minute.
Claim 9
Dependent Claim
21 words
The method of claim 3 further including mounting the chuck at a slight angle from being perpendicular to the polishing pads.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-07-20 | 1991-01-19 | 1991-07-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-07-20 | 1995-01-19 | 1995-07-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-07-20 | 1999-01-19 | 1999-07-21 | $7700.00 | Window Closed / Lapsed |