Patent US4622098A successfully refreshed from Google Patents.
US4622098A
Expired / Lapsed
US
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Method for manufacturing semiconductor strain sensor
Assignee: Toshiba Corp
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Filing: 1986-01-21
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Granted: 1986-11-11
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Expires: 2006-01-21
Abstract
Abstract A semiconductor strain sensor has a semiconductor substrate having a pair of major surfaces parallel to each other. The substrate is worked to constitute a frame and a thin diaphragm by forming a circular blind hole from one major surface. The bottom surface of the blind hole is formed in a conical shape projecting upward from the edge portion to a central portion thereof. The substrate has a thickness of not less than 0.5 mm and not less than about five times that of the diaphragm. The blind hole is formed by grinding and the inner surface of the blind hole is then etched to eliminate a scratch formed in the inner surface by grinding. Resistance layers are formed on the other major surface of the substrate. Each layer has a piezoresistance which varies in accordance with the pressure applied to the diaphragm.
Inventors
- 👤 Nobuo Ochiai
- 👤 Takashi Tsumagari
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:42
CPC Classifications
G; G01; G01L; G01L9/00; G01L9/0041; G01L9/0042; G01L9/0051; G01L9/0052; G01L9/0054; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49082; Y10T29/49103
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
118 words
A method for manufacturing a semiconductor strain sensor, comprising the steps of: forming resistance layers on one of major surfaces of a semiconductor substrate having a pair of major surfaces which are parallel to each other; forming a circular blind hole by grinding from the other major surface of the semiconductor substrate having the resistance layers and forming the bottom surface of the blind hole in a conical shape which projects upward from an edge portion to a central portion thereof, thereby working the semiconductor substrate to constitute a thin diaphragm and a frame; and etching an inner surface of the blind hole to eliminate a scratch formed in the inner surface of the blind hole by grinding.
Claim 2
Independent Claim
118 words
A method for manufacturing a semiconductor strain sensor, comprising the steps of: forming resistance layers on one of major surfaces of a semiconductor substrate having a pair of major surfaces which are parallel to each other; forming a circular blind hole by grinding from the other major surface of the semiconductor substrate having the resistance layers and forming the bottom surface of the blind hole in a conical shape which projects upward from an edge portion to a central portion thereof, thereby working the semiconductor substrate to constitute a thin diaphragm and a frame; and etching an inner surface of the blind hole to eliminate a scratch formed in the inner surface of the blind hole by grinding.
Claim 3
Dependent Claim
78 words
A method according to claim 1, wherein said step of forming the circular blind hole by grinding is performed such that a grinding wheel having an orbiting axis perpendicular to the major surfaces of the semiconductor substrate and a rotating axis inclined by a predetermined angle with respect to the orbiting axis, is driven in a planetary manner, and is moved along the orbiting axis toward the other major surface of the semiconductor substrate to grind the same.
Claim 4
Dependent Claim
60 words
A method according to claim 1, wherein said step of forming the blind hole by grinding is performed such that a grinding wheel having a grinding surface which has a conical recess corresponding to the bottom surface of the blind hole, is rotated, and is moved vertically toward the other major surface of the semiconductor substrate to grind the same.
Claim 5
Dependent Claim
16 words
A method according to claim 1, wherein said step of etching is performed by chemical etching.
Claim 6
Dependent Claim
16 words
A method according to claim 1, wherein said step of etching is performed by dry etching.
References Cited (Backward Citations)
US2992556A
Cited
DE1226806B
Cited
US3455165A
Cited
DE1648725A1
Cited
US3819431A
Cited
DE2618399A1
Cited
JPS5267584A
Cited
DE2711749A1
Cited
GB1581215A
Cited
JPS54162492A
Cited
JPS54162985A
Cited
JPS5577178A
Cited
US4236137A
Cited
US4507170A
Cited
US4443293A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-11-10 | 1990-05-12 | 1990-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-11-10 | 1994-05-12 | 1994-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-11-10 | 1998-05-12 | 1998-11-11 | $7700.00 | Window Closed / Lapsed |