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US4618844A Expired / Lapsed US ⏱️ 0.0 years remaining

Semiconductor pressure transducer

Assignee: Hitachi Ltd
•
Filing: 1983-05-12
•
Granted: 1986-10-21
•
Expires: 2003-05-12
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Abstract

Abstract In a semiconductor pressure transducer in accordance with the present invention, an oxide film is formed on a semiconductor base having a strain gauge resistor element for the purpose of protecting the strain gauge resistor element. Over the oxide film, a conductive metal film is formed which does not overlap with the strain gauge resistor element through said oxide film.

Inventors

  • 👤 Yukio Takahashi
  • 👤 Michitaka Shimazoe
  • 👤 Yoshitaka Matsuoka

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 10:57
CPC Classifications
G; G01; G01L; G01L9/00; G01L9/0041; G01L9/0051; G01L9/0052; G01L9/0054

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 97 words
A semiconductor pressure transducer comprising: a base comprising a semiconductor monocrystal; a strain gauge resistor element formed on said base; an oxide film formed on said base in contact with said strain gauge resistor element for protecting said strain gauge resistor element; and a conductive layer formed on said oxide film, said layer not overlapping said strain gauge resistor element through said oxide film, being adjacent two opposed sides of said strain gauge element and functioning to cause movable ions within and on the oxide film in proximity to the strain gauge resistor element to be fixed.
Claim 2
Dependent Claim 97 words
A semiconductor pressure transducer comprising: a base comprising a semiconductor monocrystal; a strain gauge resistor element formed on said base; an oxide film formed on said base in contact with said strain gauge resistor element for protecting said strain gauge resistor element; and a conductive layer formed on said oxide film, said layer not overlapping said strain gauge resistor element through said oxide film, being adjacent two opposed sides of said strain gauge element and functioning to cause movable ions within and on the oxide film in proximity to the strain gauge resistor element to be fixed.
Claim 3
Dependent Claim 47 words
A semiconductor pressure transducer according to claim 1, wherein the two opposed sides of said strain gauge resistor element extend along a longitudinal direction and said conductive layer comprises two conductive films provided adjacent to both sides of said strain gauge resistor element along its longitudinal direction.
Claim 4
Dependent Claim 16 words
A semiconductor pressure transducer according to claim 1, wherein said conductive layer is made of aluminium.
Claim 5
Dependent Claim 27 words
A semiconductor pressure transducer according to claim 1, wherein the length of said conductive layer is 0.6 to 0.8 the length of said strain gauge resistor element.
Claim 6
Dependent Claim 29 words
A semiconductor pressure transducer according to claim 1, wherein said base has a (100) surface and said strain gauge resistor element is arranged in parallel with a <110> axis.
Claim 7
Dependent Claim 51 words
A semiconductor pressure transducer according to claim 2, wherein said conductive films provided on both sides of said strain gauge resistor element are coupled to each other by an electrical connection means which is so positioned on said oxide film and crosses said strain gauge resistor element over said oxide film.
Claim 8
Dependent Claim 18 words
A semiconductor pressure transducer according to claim 6, said electrical connection means is thinner than said conductive films.
Claim 9
Dependent Claim 138 words
A semiconductor pressure transducer comprising: a base comprising a n-type silicon monocrystal having a thin strain causing portion on a central part and a thick fixed portion on an exterior periphery; a p-type strain gauge resistor element formed in said strain causing portion; an oxide film formed on said base in contact with said strain gauge resistor element for protecting said strain gauge resistor element; aluminum wiring formed on said oxide film for outputting the output of said strain gauge resistor element; and a conductive layer formed on said oxide film, said layer not overlapping said strain gauge resistor element through said oxide film, being adjacent two opposed sides of said strain gauge resistor element and functioning to cause movable ions within and on the oxide film in proximity to the strain gauge resistor element to be fixed.
Claim 10
Dependent Claim 138 words
A semiconductor pressure transducer comprising: a base comprising a n-type silicon monocrystal having a thin strain causing portion on a central part and a thick fixed portion on an exterior periphery; a p-type strain gauge resistor element formed in said strain causing portion; an oxide film formed on said base in contact with said strain gauge resistor element for protecting said strain gauge resistor element; aluminum wiring formed on said oxide film for outputting the output of said strain gauge resistor element; and a conductive layer formed on said oxide film, said layer not overlapping said strain gauge resistor element through said oxide film, being adjacent two opposed sides of said strain gauge resistor element and functioning to cause movable ions within and on the oxide film in proximity to the strain gauge resistor element to be fixed.
Claim 11
Dependent Claim 34 words
A semiconductor pressure transducer according to claim 8, wherein said base has a (100) surface and said strain gauge resistor element is arranged in parallel with the <110> axis and near said fixed portion.
Claim 12
Dependent Claim 47 words
A semiconductor pressure transducer according to claim 8 wherein the two opposed sides of said strain gauge resistor element extend along its longitudinal direction and said conductive layer comprises two conductive films provided adjacent to both sides of said strain engage resistor element along its longitudinal direction.
Claim 13
Dependent Claim 16 words
A semiconductor pressure transducer according to claim 8, wherein said conductive layer is made of aluminium.
Claim 14
Dependent Claim 27 words
A semiconductor pressure transducer according to claim 8, wherein the length of said conductive layer is 0.6 to 0.8 the length of said strain gauge resistor element.
Claim 15
Dependent Claim 29 words
A semiconductor pressure transducer according to claim 8, wherein said base has a (100) surface and said strain gauge resistor element is arranged in parallel with a <110> axis.
Claim 16
Dependent Claim 51 words
A semiconductor pressure transducer according to claim 10, wherein said conductive films provided on both sides of said strain gauge resistor element are coupled to each other by an electrical connection means which is so positioned on said oxide film and crosses said strain gauge resistor element over said oxide film.
Claim 17
Dependent Claim 18 words
A semiconductor pressure transducer according to claim 14, wherein electrical connection means is thinner than said conductive films.

References Cited (Backward Citations)

US3456226A Cited
US3662312A Cited
US3961358A Cited
US4125820A Cited
US4151502A Cited
US4173900A Cited
JPS5533092A Cited
US4364276A Cited
US4317126A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-10-20 1990-04-21 1990-10-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-10-20 1994-04-21 1994-10-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-10-20 1998-04-21 1998-10-21 $7700.00 Window Closed / Lapsed

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