US4456522A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Support and anchoring mechanism for membranes in selectively responsive field effect devices
Assignee: Ethicon Inc
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Filing: 1981-09-23
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Granted: 1984-06-26
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Expires: 2001-09-23
Abstract
Abstract In the formation of a chemically sensitive field effect device, prior to formation of the gate membrane, an aluminum pad is disposed over the gate, and a polyimide layer is disposed thereover. Photoresist and etching steps produce openings in the polyimide to form a gridwork which is anchored to the device on the periphery of the gate. The aluminum layer is etched completely away, forming a void defined by the suspended polyimide mesh on one side, and the gate insulator on the other. Polymeric membrane is formed in the void by insertion in liquid form.
Inventors
- 👤 Gary F. Blackburn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:53
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/403; G01N27/414
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
152 words
A method for fabricating selectively responsive field effect devices whose electrical charcteristics are responsive to a given substance, comprising the steps of: (a) providing at least one of said devices including an insulated gate region; (b) covering at least said gate region with a first material; (c) covering at least said first material with a second material, said second material being coupled to said device at least at predetermined points about the periphery of said gate region; (d) selectively forming openings through said second material to form a grid pattern; (e) selectively removing said first material from beneath said second material in said gate region; and (f) applying membrane material through said grid openings to fill at least the void between said gate region and said second material; (g) whereby said ambient substances may react with said device through direct exposure to said membrane, whilst said grid protects and anchors said membrane.
Claim 2
Independent Claim
152 words
A method for fabricating selectively responsive field effect devices whose electrical charcteristics are responsive to a given substance, comprising the steps of: (a) providing at least one of said devices including an insulated gate region; (b) covering at least said gate region with a first material; (c) covering at least said first material with a second material, said second material being coupled to said device at least at predetermined points about the periphery of said gate region; (d) selectively forming openings through said second material to form a grid pattern; (e) selectively removing said first material from beneath said second material in said gate region; and (f) applying membrane material through said grid openings to fill at least the void between said gate region and said second material; (g) whereby said ambient substances may react with said device through direct exposure to said membrane, whilst said grid protects and anchors said membrane.
Claim 3
Dependent Claim
34 words
A method as described in claim 1 wherein said first material is aluminum, and said step of selectively removing said first material comprises etching said aluminum away, substantially completely, using an acid etchant solution.
Claim 4
Dependent Claim
47 words
A method as described in claim 1 wherein said second material is polyimide, and wherein said step of selectively forming openings comprises the steps of developing a gridwork pattern of photoresist over said second material, and etching the openings in said polyimide through to said first material.
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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) | 1987-06-26 | 1987-12-26 | 1988-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-06-26 | 1991-12-26 | 1992-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-06-26 | 1995-12-26 | 1996-06-26 | $7700.00 | Window Closed / Lapsed |