US4592824A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Miniature liquid junction reference electrode and an integrated solid state electrochemical sensor including the same
Assignee: CSEM Centre Suisse d'Electronique et de Microtechnique SA - Recherche et Développement
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Filing: 1985-09-13
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Granted: 1986-06-03
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Expires: 2005-09-13
Abstract
Abstract This invention relates to a miniature reference electrode of the liquid junction-type which is utilized by an integrated electrochemical sensor, which functions as an Ion Sensitive Field Effect Transistor.
Inventors
- 👤 Rosemary L. Smith
- 👤 Scott Collins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:23
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/403; G01N27/414; G01N27/4148; G01N27/28; G01N27/30; G01N27/301
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
70 words
A miniature reference electrode providing both electrical connection and a liquid junction between a reference liquid solution and a solution to be tested, comprising: a substrate provided with a cavity to hold said reference liquid solution; a membrane comprising porous silicon closing a first end of said cavity; means for applying fixed control voltage to said reference liquid solution; and means for hermetically closing a second end of said cavity.
Claim 2
Dependent Claim
70 words
A miniature reference electrode providing both electrical connection and a liquid junction between a reference liquid solution and a solution to be tested, comprising: a substrate provided with a cavity to hold said reference liquid solution; a membrane comprising porous silicon closing a first end of said cavity; means for applying fixed control voltage to said reference liquid solution; and means for hermetically closing a second end of said cavity.
Claim 3
Dependent Claim
14 words
A miniature reference electrode according to claim 1, wherein said substrate comprises insulating material.
Claim 4
Dependent Claim
13 words
A miniature reference electrode according to claim 1, wherein said substrate comprises silicon.
Claim 5
Dependent Claim
24 words
A miniature reference electrode according to claim 1, wherein said means for applying the fixed control voltage comprises an electrode disposed in said cavity.
Claim 6
Dependent Claim
30 words
A miniature reference electrode according to claim 1, wherein said means for hermetically closing said second end of the cavity comprises a glass cover which is sealed to said substrate.
Claim 7
Dependent Claim
27 words
A miniature reference electrode according to claim 5, wherein said means for applying the control voltage comprises an electrode formed on the surface of said glass cover.
Claim 8
Dependent Claim
79 words
An integrated chemical sensor including an Ion Sensitive Field Effect Transistor formed in a silicon substrate and a miniature reference electrode on said silicon substrate, wherein said electrode comprises: a cavity provided in said silicon substrate to hold a reference liquid solutiion; a membrane comprising porous silicon, said membrane closing a first end of said cavity; means for applying a fixed control voltage to said reference liquid solution; and means for hermetically closing a second end of said cavity.
Claim 9
Dependent Claim
79 words
An integrated chemical sensor including an Ion Sensitive Field Effect Transistor formed in a silicon substrate and a miniature reference electrode on said silicon substrate, wherein said electrode comprises: a cavity provided in said silicon substrate to hold a reference liquid solutiion; a membrane comprising porous silicon, said membrane closing a first end of said cavity; means for applying a fixed control voltage to said reference liquid solution; and means for hermetically closing a second end of said cavity.
Claim 10
Dependent Claim
29 words
An integrated sensor according to claim 7, wherein said porous silicon membrane is formed on the same side of said silicon substrate as the Ion Sensitive Field Effect Transistor.
References Cited (Backward Citations)
US2925370A
Cited
US4508613A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-06-02 | 1989-12-02 | 1990-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-06-02 | 1993-12-02 | 1994-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-06-02 | 1997-12-02 | 1998-06-03 | $7700.00 | Window Closed / Lapsed |