US4632884A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Marked single-crystal III-V group compound semiconductor wafer
Assignee: Sumitomo Electric Industries Ltd
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Filing: 1984-11-19
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Granted: 1986-12-30
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Expires: 2004-11-19
Abstract
Abstract In a rectangular, square or other shaped single-crystal wafer of a III-V group compound semiconductor, one corner of the wafer is cut off, provided with a marking, or the wafer has a part of the original shape of the grown single-crystal ingot left intact on one side of the wafer. With the wafers thus formed, it can be distinguished between the front and back sides of the wafer, or also the direction in which a V groove etch is to occur can be identified.
Inventors
- 👤 Osamu Shikatani
- 👤 Jun Yamaguchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 19:36
CPC Classifications
H; H10; H10W; H10W46/00; H10D; H10D62/00; H10D62/10; H10D62/117; H10W46/201; Y; Y10; Y10S; Y10S148/00; Y10S148/102; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12681
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
59 words
A rectangular single-crystal wafer of a III-V group compound for semiconductor manufacture having an indexing mark for an operator to recognize the front and back surfaces to orient a face for etching, said indexing mark comprising one corner cut off the rectangle so that the position of the cut off corner may be used to orient the desired surface.
Claim 2
Dependent Claim
59 words
A rectangular single-crystal wafer of a III-V group compound for semiconductor manufacture having an indexing mark for an operator to recognize the front and back surfaces to orient a face for etching, said indexing mark comprising one corner cut off the rectangle so that the position of the cut off corner may be used to orient the desired surface.
References Cited (Backward Citations)
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US3710101A
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US3783044A
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US3742315A
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US4489139A
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US4468857A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-12-29 | 1990-06-30 | 1990-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-12-29 | 1994-06-30 | 1994-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-12-29 | 1998-06-30 | 1998-12-30 | $7700.00 | Window Closed / Lapsed |