US4897369A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for shaping the edges of slices of semiconductor material
Assignee: STMicroelectronics SA
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Filing: 1988-06-22
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Granted: 1990-01-30
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Expires: 2008-06-22
Abstract
Abstract The invention concerns a method in which the edge of the slices is made to slide in contact with the surfaces of a pad soaked in acid substances and in which, during the process, the areas of the edge of the slices that have been in contact with the pad are periodically washed with a special liquid.
Inventors
- 👤 Giorgio Beretta
- 👤 Antonino Inserra
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 09:33
CPC Classifications
H; H10; H10P; H10P72/00; H10P72/04; H10P72/0402; H10P72/0406; H10P72/0411; H10P72/0416; H10P50/00
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
125 words
A method of shaping an edge of a slice of a semiconductor material, comprising the steps of: (a) sliding an edge of a slice of a semiconductor material in cyclic contact with a surface of a pad soaked with an acid substance capable of dissolving material from said slice; (b) periodically washing portions of the edge of said slice with deionized water; and (c) contacting said portions after washing with the deionized water again with said pad, said deionized water being provided in a bath below said pad, said slice is round, and said edge is slid in contact with said surface of said pad by rotating said slice to displace said edge through a notch formed in said pad and then through said bath.
Claim 2
Independent Claim
125 words
A method of shaping an edge of a slice of a semiconductor material, comprising the steps of: (a) sliding an edge of a slice of a semiconductor material in cyclic contact with a surface of a pad soaked with an acid substance capable of dissolving material from said slice; (b) periodically washing portions of the edge of said slice with deionized water; and (c) contacting said portions after washing with the deionized water again with said pad, said deionized water being provided in a bath below said pad, said slice is round, and said edge is slid in contact with said surface of said pad by rotating said slice to displace said edge through a notch formed in said pad and then through said bath.
Claim 3
Dependent Claim
15 words
The method defined in claim 1, further comprising the step of continuously replacing said bath.
Claim 4
Dependent Claim
15 words
The method defined in claim 2 wherein said slice is rotated in a vertical plane.
Claim 5
Dependent Claim
26 words
The method defined in claim 3 wherein a plurality of said slices are rotated simultaneously through respective notches in said pad and then into said bath.
Claim 6
Dependent Claim
24 words
The method defined in claim 4 wherein said slices are rotated by supporting them on a pair of parallel rollers and rotating said rollers.
References Cited (Backward Citations)
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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) | 1993-01-29 | 1993-07-31 | 1994-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-29 | 1997-07-31 | 1998-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-29 | 2001-07-31 | 2002-01-30 | $7700.00 | Window Closed / Lapsed |