US3691694A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wafer polishing machine
Assignee: International Business Machines Corp
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Filing: 1970-11-02
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Granted: 1972-09-19
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Expires: 1990-11-02
Abstract
Abstract This patent relates to apparatus for removing and polishing opposite surfaces of a semiconductor wafer. The apparatus comprises a rotatable platen having an abrasive upper surface upon which a mask having suitable apertures therein for receiving wafers is positioned. A hoop is connected to the mask for imparting rotation thereof separately from the rotation of the platen. Overlying the mask and wafers is a second lapping means having an abrasive surface thereon for applying a uniform pressure upon the opposite surface of the wafer. Separate drive means cooperate with the second lapping means for separately driving the lapping means os that upon rotation of the platen, hoop and mask, and second lapping means the opposite planar surfaces of the wafer is brought into coplanarity while being polished. During the operation of the apparatus the surface of the wafers is continuously wetted with an excess quantity of a displacement plating solution containing, for example, a cupric or silver nitrate and a fluoride anion, the solution being maintained preferably at a pH of less than 7.
Inventors
- 👤 Frederick E Goetz
- 👤 James R Hause
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 12:59
CPC Classifications
B; B24; B24B; B24B37/00; B24B37/04; B24B37/07; B24B37/08
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
149 words
Apparatus for removing material from opposite sides of a workpiece; said apparatus comprising first lapping means engagable with one surface of said workpiece, and means for imparting rotational motion to said first lapping means against said one surface of said workpiece; workpiece holding means engagable with said workpiece for permitting relative motion between said workpiece and said first lapping means; and means for imparting rotational movement to said workpiece holding means independent of rotational motion of said first lapping means; second lapping means superimposed on said holder and first lapping means for registry with the opposite side of said workpiece, said second lapping means having an axis of rotation coincidental with the axis of rotation of said workpiece holding means, and means for imparting independent rotational movement to said second lapping means whereby material may be removed from opposite sides of a workpiece retained by said workpiece holding means.
Claim 2
Dependent Claim
149 words
Apparatus for removing material from opposite sides of a workpiece; said apparatus comprising first lapping means engagable with one surface of said workpiece, and means for imparting rotational motion to said first lapping means against said one surface of said workpiece; workpiece holding means engagable with said workpiece for permitting relative motion between said workpiece and said first lapping means; and means for imparting rotational movement to said workpiece holding means independent of rotational motion of said first lapping means; second lapping means superimposed on said holder and first lapping means for registry with the opposite side of said workpiece, said second lapping means having an axis of rotation coincidental with the axis of rotation of said workpiece holding means, and means for imparting independent rotational movement to said second lapping means whereby material may be removed from opposite sides of a workpiece retained by said workpiece holding means.
Claim 3
Dependent Claim
17 words
Apparatus in accordance with claim 1 wherein said first lapping means comprises a platen mounted for rotation.
Claim 4
Dependent Claim
27 words
Apparatus in accordance with claim 1 wherein said workpiece holding means comprises a mask including means defining at least one aperture therein for engagement with said workpiece.
Claim 5
Dependent Claim
32 words
Apparatus in accordance with claim 3 including a hoop connected to said mask adjacent the periphery thereof, said second lapping means being dimensioned for insertion in said hoop superimposed of said mask.
Claim 6
Dependent Claim
63 words
Apparatus in accordance with claim 4 wherein said second lapping means comprises a head and a pressure plate mounted interiorally of said hoop, means defining a conduit through said plate for supplying a fluid medium to the surface of said mask, and means associated with said plate to permit levelling of said plate against the surface of said workpiece held in said mask.
Claim 7
Dependent Claim
51 words
Apparatus in accordance with claim 5 including radially extending slots eminating from said conduit of said plate, between said conduit and a terminal edge of said plate, whereby fluid medium passing through said conduit may progress outwardly along said radial slots as relative motion occurs between said mask and said plate.
Claim 8
Dependent Claim
46 words
Apparatus in accordance with claim 6 wherein said hoop includes a radially extending flat portion having a plurality of grooves therein to permit said fluid medium to pass outwardly from said hoop upon a supply of fluid medium being provided to said conduit of said plate.
Claim 9
Dependent Claim
28 words
Apparatus in accordance with claim 7 including means for connecting said mask at spaced locations to said hoop intermediate at least some of said grooves in said hoop.
Claim 10
Dependent Claim
153 words
A machine for removing a portion of the surface from opposite sides of a workpiece, said machine comprising: a platen having an abrasive on at least the upper surface thereof; first drive means for imparting rotation to said platen; a mask superimposed of said platen and including means defining apertures in said mask for receiving a plurality of workpieces thErein; second drive means connected to said mask for imparting rotation to said mask separately from said platen; and plate means superimposed of all of said apertures in said mask for exerting pressure on workpieces held in said apertures of said mask, said plate means having an abrasive surface adapted for registry with said workpieces during abrasion of said workpieces; and third drive means for independently imparting motion to said plate means whereby material may be removed from opposite sides of said workpieces upon relative rotation occurring between said platen, mask and plate means.
Claim 11
Dependent Claim
153 words
A machine for removing a portion of the surface from opposite sides of a workpiece, said machine comprising: a platen having an abrasive on at least the upper surface thereof; first drive means for imparting rotation to said platen; a mask superimposed of said platen and including means defining apertures in said mask for receiving a plurality of workpieces thErein; second drive means connected to said mask for imparting rotation to said mask separately from said platen; and plate means superimposed of all of said apertures in said mask for exerting pressure on workpieces held in said apertures of said mask, said plate means having an abrasive surface adapted for registry with said workpieces during abrasion of said workpieces; and third drive means for independently imparting motion to said plate means whereby material may be removed from opposite sides of said workpieces upon relative rotation occurring between said platen, mask and plate means.
Claim 12
Dependent Claim
31 words
Apparatus in accordance with claim 9 including a hoop connected to said mask adjacent the periphery thereof, said plate means being dimensioned for insertion in said hoop superimposed of said mask.
Claim 13
Dependent Claim
66 words
Apparatus in accordance with claim 10 including a head connected to said plate means, said plate means being mounted interiorally of said hoop, means defining a conduit through said plate means for supplying a fluid medium to the surface of said mask, and means associated with said plate means to permit levelling of said plate means against the surface of said workpiece held in said mask.
Claim 14
Dependent Claim
54 words
Apparatus in accordance with claim 11 including radially extending slots eminating from said conduit of said plate means, between said conduit and a terminal edge of said plate means, whereby fluid medium passing through said conduit may progress outwardly along said radial slots as relative motion occurs between said mask and said plate means.
Claim 15
Dependent Claim
47 words
Apparatus in accordance with claim 12 wherein said hoop includes a radially extending flat portion having a plurality of grooves therein to permit said fluid medium to pass outwardly from said hoop upon a supply of fluid medium being provided to said conduit of said plate means.
Claim 16
Dependent Claim
28 words
Apparatus in accordance with claim 13 including means for connecting said mask at spaced locations to said hoop intermediate at least some of said grooves in said hoop.
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) | 1975-09-19 | 1976-03-20 | 1976-09-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-19 | 1980-03-20 | 1980-09-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-19 | 1984-03-20 | 1984-09-19 | $7700.00 | Window Closed / Lapsed |