US4499440A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low reflectivity electrodes in semiconductive SAW devices
Assignee: RTX Corp
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Filing: 1983-08-22
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Granted: 1985-02-12
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Expires: 2003-08-22
Abstract
Abstract Low reflectivity electrodes (2-4) are formed within recesses extending from a major surface of a semiconductive and piezoelectric substrate (1) (such as gallium arsenide) so as to reduce SAW reflectivity from the electrodes.
Inventors
- 👤 Thomas W. Grudkowski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 03:08
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/02; H03H9/125; H03H9/145; H03H9/14538; H03H9/02535; H03H9/02543; H03H9/02566; H03H9/02818; H03H9/02842; H03H9/02858; H03H9/02881
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
58 words
A surface acoustic wave device comprising: a substrate of semiconductive gallium arsenide and a plurality of electrodes comprising aluminum disposed on said substrate, characterized by: said electrodes being formed in recesses (slots, grooves) extending into said substrate from a major surface thereof, whereby the surface of the electrodes is essentially coplanar with said major surface of said substrate.
Claim 2
Dependent Claim
58 words
A surface acoustic wave device comprising: a substrate of semiconductive gallium arsenide and a plurality of electrodes comprising aluminum disposed on said substrate, characterized by: said electrodes being formed in recesses (slots, grooves) extending into said substrate from a major surface thereof, whereby the surface of the electrodes is essentially coplanar with said major surface of said substrate.
Claim 3
Dependent Claim
18 words
A surface acoustic wave device according to claim 1 wherein said electrodes comprise layers of chromium and aluminum.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-02-12 | 1988-08-13 | 1989-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-12 | 1992-08-13 | 1993-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-12 | 1996-08-13 | 1997-02-12 | $7700.00 | Window Closed / Lapsed |