Patent US5690841A successfully refreshed from Google Patents.
US5690841A
Expired / Lapsed
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Method of producing cavity structures
Assignee: LAGRUMMET DECEMBER 1047 AB
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Filing: 1994-12-08
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Granted: 1997-11-25
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Expires: 2014-12-08
Abstract
Abstract A method of producing sealed cavity structures in the surface layer of a selectively etchable substrate (1), comprises: a) depositing a masking layer (2) of etchable material on the substrate (1), b) by means of etching, opening at least one hole (3) in the masking layer (2) down to the substrate surface, c) through said hole or holes (3) in the masking layer (2) selectively etching the substrate (1) in under the masking layer (2) so as to form one more cavities (4) which extend under the masking layer, and d) sealing said hole or holes (3) in the masking layer (2).
Inventors
- 👤 Håkan Elderstig
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 10:13
CPC Classifications
B; B81; B81C; B81C1/00; B81C1/00015; B81C1/00023; B81C1/00047; B01; B01L; B01L3/00; B01L3/50; B01L3/502; B01L3/5027; B01L3/502707; G; G01; G01L; G01L9/00; G01L9/0041; G01L9/0042; B01L2200/00; B01L2200/12; B01L2300/00; B01L2300/06; B01L2300/0627; B01L2300/0645
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
107 words
A method of producing sealed cavity structures in the surface layer of a selectively etchable substrate, comprising the steps of: a) depositing a masking layer of etchable polysilicon material on the substrate wherein said substrate is silicon dioxide, b) etching at least one hole in the masking layer down to the substrate surface, c) selectively etching the substrate in under the masking layer through said hole or holes so as to form one or more cavities which extend under the masking layer; and d) sealing said hole or holes in the masking layer by oxidation of polysilicon to silicon dioxide, and thereby expansion of the masking layer.
Claim 2
Independent Claim
107 words
A method of producing sealed cavity structures in the surface layer of a selectively etchable substrate, comprising the steps of: a) depositing a masking layer of etchable polysilicon material on the substrate wherein said substrate is silicon dioxide, b) etching at least one hole in the masking layer down to the substrate surface, c) selectively etching the substrate in under the masking layer through said hole or holes so as to form one or more cavities which extend under the masking layer; and d) sealing said hole or holes in the masking layer by oxidation of polysilicon to silicon dioxide, and thereby expansion of the masking layer.
Claim 3
Dependent Claim
33 words
The method according to claim 1, further comprising making a plurality of holes arranged adjacent to each other in the masking layer; and etching a continuous cavity through the holes in the substrate.
Claim 4
Dependent Claim
21 words
The method according to claim 2, characterized in that one or more of said holes in the masking layer are oblong.
Claim 5
Dependent Claim
20 words
The method of claim 3 further comprising deposition of a silicon dioxide layer on the substrate surface and hole walls.
Claim 6
Dependent Claim
33 words
The method according to claim 4, further comprising making a plurality of holes arranged adjacent to each other in the masking layer; and etching a continuous cavity through the holes in the substrate.
Claim 7
Dependent Claim
21 words
The method according to claim 4, characterized in that one or more of said holes in the masking layer are oblong.
Claim 8
Dependent Claim
21 words
The method according to claim 1, characterized in that one or more of said holes in the masking layer are oblong.
Claim 9
Dependent Claim
17 words
The method according to claim 1, characterized in that said cavity or cavities comprise a capillary channel.
Claim 10
Dependent Claim
26 words
The method according to claim 1, characterized in that the structure of said cavity is a liquid or gas flow structure for a chemical analysis system.
Claim 11
Dependent Claim
18 words
The method according to claim 1, characterized in that the structure of said cavity forms a membrane structure.
Claim 12
Dependent Claim
19 words
The method according to claim 1, further comprising integrating electrical, electronic and/or optical components in the sealed cavity structure.
References Cited (Backward Citations)
US3887404A
Cited
US3880684A
Cited
US4996082A
Cited
US4885054A
Cited
US4908921A
Cited
US5127990A
Cited
US5177661A
Cited
US4996080A
Cited
JPH0529479A
Cited
US5204690A
Cited
EP0566929A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-11-24 | 2001-05-26 | 2001-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-11-24 | 2005-05-26 | 2005-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-11-24 | 2009-05-26 | 2009-11-25 | $7700.00 | Window Closed / Lapsed |