US5982709A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Acoustic transducers and method of microfabrication
Assignee: Leland Stanford Junior University
•
Filing: 1998-03-31
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Granted: 1999-11-09
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Expires: 2018-03-31
Abstract
Abstract There is provided an acoustic transducer which includes a membrane of selected size and shape supported at its edges spaced from a first conductive electrode by an integral support structure with the second conductive electrode comprising a thin metal film on the membrane. The active membrane area is undisturbed by etch vias.
Inventors
- 👤 Igal Ladabaum
- 👤 Xuecheng Jin
- 👤 Butrus T. Khuri-Yakub
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 23:15
CPC Classifications
H; H10; H10N; H10N30/00; H10N30/20; H10N30/204; H10N30/2047
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
78 words
An acoustic transducer comprising a silicon substrate forming a first electrode, a membrane of selected shape supported at its edges spaced from said substrate by an integral support structure of the same material as the membrane, and a conductive film is carried by said membrane to form a second electrode of said acoustic transducer characterized in that the support structure includes reservoirs and tortuous channels communicating between the reservoirs and the space between the substrate and the membrane.
Claim 2
Dependent Claim
78 words
An acoustic transducer comprising a silicon substrate forming a first electrode, a membrane of selected shape supported at its edges spaced from said substrate by an integral support structure of the same material as the membrane, and a conductive film is carried by said membrane to form a second electrode of said acoustic transducer characterized in that the support structure includes reservoirs and tortuous channels communicating between the reservoirs and the space between the substrate and the membrane.
Claim 3
Dependent Claim
17 words
An acoustic transducer as in claim 1 in which said membrane and support structure are silicon nitride.
Claim 4
Dependent Claim
32 words
An acoustic transducer as in claim 1 in which said membrane and integral support structures are polysilicon and a silicon nitride layer is interposed between said support structure and said silicon substrate.
Claim 5
Dependent Claim
21 words
An acoustic transducer as in claim 2 in which said silicon nitride support supports the membrane directly on said silicon substrate.
Claim 6
Dependent Claim
24 words
An acoustic transducer as in claim 1, 2, 3 or 4 which includes a plurality of silicon nitride membranes of selected size and shape.
Claim 7
Dependent Claim
43 words
An acoustic transducer as in claim 1, 2, 3 or 4 in which the reservoirs and channels are sealed to seal the space between the substrate and the membrane to form a sealed cavity whereby the transducer can be immersed in a liquid.
Claim 8
Dependent Claim
25 words
An acoustic transducer as in claim 5 in which the support structure includes a plurality of spaced posts each including tortuous channels and a reservoir.
Claim 9
Dependent Claim
26 words
An acoustic transducer as in claim 1 including a plurality of spaced support posts spaced from the edge support structure to provide a dual mode transducer.
Claim 10
Dependent Claim
18 words
An acoustic transducer as in claim 8 in which the support posts include a reservoir and tortuous channels.
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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) | 2002-11-08 | 2003-05-10 | 2003-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-11-08 | 2007-05-10 | 2007-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-11-08 | 2011-05-10 | 2011-11-09 | $7700.00 | Window Closed / Lapsed |