US4130813A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Surface wave device having enhanced reflectivity gratings
Assignee: Raytheon Co
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Filing: 1977-05-23
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Granted: 1978-12-19
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Expires: 1997-05-23
Abstract
Abstract Surface acoustic wave devices are disclosed which have enhanced reflectivity gratings with conductive stripes between grooves in the substrate or conductive stripes within the grooves. For lithium niobate substrates, aluminum stripes coupled together and positioned between grooves or unconnected and positioned within the grooves are preferred. For quartz substrates, gold stripes within the grooves are used. Methods for fabricating such structures are also disclosed.
Inventors
- 👤 Frank Sandy
- 👤 Clarence J. Dunnrowicz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 07:28
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/02; H03H9/125; H03H9/145; H03H9/14538; G; G10; G10K; G10K11/00; G10K11/36; H03H3/00; H03H3/007; H03H3/08; H03H9/02535; H03H9/02637; H03H9/02653; H03H9/02685; H03H9/02716; H03H9/02795; Y; Y10; Y10T; Y10T29/00; Y10T29/42
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
78 words
In combination: a substrate for supporting surface wave propagation; and one or more means for reflecting surface waves upon said substrate, said reflecting means having a plurality of substantially parallel grooves within said substrate and a plurality of metal stripes positioned on the surface of said substrate, one of said stripes being located between adjacent ones of said grooves, the width of said grooves and said metal stripes being substantially one-half the wavelength of said reflected surface waves.
Claim 2
Dependent Claim
78 words
In combination: a substrate for supporting surface wave propagation; and one or more means for reflecting surface waves upon said substrate, said reflecting means having a plurality of substantially parallel grooves within said substrate and a plurality of metal stripes positioned on the surface of said substrate, one of said stripes being located between adjacent ones of said grooves, the width of said grooves and said metal stripes being substantially one-half the wavelength of said reflected surface waves.
Claim 3
Dependent Claim
17 words
The combination of claim 1 wherein: at least some of said metal stripes are coupled in parallel.
Claim 4
Dependent Claim
14 words
The combination of claim 2 wherein the metal of said metal stripes comprises: aluminum.
Claim 5
Dependent Claim
11 words
The combination of claim 3 wherein said substrate comprises: lithium niobate.
Claim 6
Dependent Claim
15 words
The combination of claim 2 further comprising: one or more transducers coupled to said substrate.
Claim 7
Dependent Claim
72 words
In combination: a substrate for supporting surface wave propagation; and one or more means for reflecting surface waves upon said substrate, said reflecting means having a plurality of substantially parallel grooves within said substrate and metal stripes positioned within at least some of said grooves, the width of said grooves and said metal stripes and the distance between adjacent ones of said grooves being substantially one-half the wavelength of reflected surface waves.
Claim 8
Dependent Claim
72 words
In combination: a substrate for supporting surface wave propagation; and one or more means for reflecting surface waves upon said substrate, said reflecting means having a plurality of substantially parallel grooves within said substrate and metal stripes positioned within at least some of said grooves, the width of said grooves and said metal stripes and the distance between adjacent ones of said grooves being substantially one-half the wavelength of reflected surface waves.
Claim 9
Dependent Claim
11 words
The combination of claim 13 wherein said substrate comprises: lithium niobate.
Claim 10
Dependent Claim
14 words
The combination of claim 7 wherein the metal of said metal stripes comprises: aluminum.
Claim 11
Dependent Claim
20 words
The combination of claim 8 wherein: the height of said metal stripes is less than the depth of said grooves.
Claim 12
Dependent Claim
10 words
The combination of claim 6 wherein: said substrate comprises quartz.
Claim 13
Dependent Claim
14 words
The combination of claim 10 wherein the metal of said metal stripes comprises: gold.
Claim 14
Dependent Claim
23 words
The combination of claim 11 further comprising: a layer of chromium positioned between said gold and at least one surface of said grooves.
Claim 15
Dependent Claim
15 words
The combination of claim 6 further comprising: one or more transducers coupled to said substrate.
Claim 16
Dependent Claim
130 words
A surface wave filter device comprising in combination: a substrate for supporting surface wave propagation; an input transducer coupled to said substrate for launching surface waves on said substrate in two opposed directions; an output transducer for receiving at least a portion of the surface waves launched by said input transducer; and at least four frequency selective surface wave reflecting means for directing at least portions of said surface waves launched by said input transducer, each of said reflecting means comprising a plurality of substantially parallel grooves within said substrate and a plurality of metal stripes positioned between said grooves, one of said stripes being located between adjacent ones of said grooves, the width of said grooves and said stripes being substantially one-half the wavelength of the reflected surface waves.
Claim 17
Dependent Claim
130 words
A surface wave filter device comprising in combination: a substrate for supporting surface wave propagation; an input transducer coupled to said substrate for launching surface waves on said substrate in two opposed directions; an output transducer for receiving at least a portion of the surface waves launched by said input transducer; and at least four frequency selective surface wave reflecting means for directing at least portions of said surface waves launched by said input transducer, each of said reflecting means comprising a plurality of substantially parallel grooves within said substrate and a plurality of metal stripes positioned between said grooves, one of said stripes being located between adjacent ones of said grooves, the width of said grooves and said stripes being substantially one-half the wavelength of the reflected surface waves.
Claim 18
Dependent Claim
20 words
The combination of claim 14 wherein: said substrate comprises lithium niobate; and said metal of said metal stripes comprises aluminum.
Claim 19
Dependent Claim
13 words
The combination of claim 15 wherein: said metal stripes are coupled in parallel.
Claim 20
Dependent Claim
36 words
The combination of claim 15 wherein: said reflecting means are four in number; and said reflecting means are positioned to form a substantially rectangular propagation path for surface waves propagating between said input and output transducers.
Claim 21
Independent Claim
75 words
The method comprising the steps of: providing a substrate of lithium niobate material having at least one surface adapted for propagation of surface waves thereupon; covering at least a portion of said surface with a layer of aluminum metal; removing portions of said layer of metal in the form of a plurality of parallel stripes; and removing portions of said substrate lying beneath the removed portions of said layer of metal to a predetermined depth.
Claim 22
Independent Claim
75 words
The method comprising the steps of: providing a substrate of lithium niobate material having at least one surface adapted for propagation of surface waves thereupon; covering at least a portion of said surface with a layer of aluminum metal; removing portions of said layer of metal in the form of a plurality of parallel stripes; and removing portions of said substrate lying beneath the removed portions of said layer of metal to a predetermined depth.
Claim 23
Dependent Claim
48 words
The method of claim 18 wherein said step of removing portions of said layer comprises the step of: removing predetermined parts of the remaining portions of said metal layer so as to leave the finally remaining portions of said metal layer in the form of parallel interconnected stripes.
Claim 24
Dependent Claim
17 words
The method of claim 18 wherein said step of removing portions of said substrate comprises: ion etching.
Claim 25
Independent Claim
102 words
The method comprising the steps of: providing a substrate of material having at least one surface adapted for propagation of surface waves thereupon; covering at least portions of said surface with a first layer of metal; removing portions of said first layer of metal in the form of a plurality of parallel stripes; removing portions of said substrate lying beneath the removed portions of said first layer of metal to a predetermined depth to form a plurality of grooves in said substrate; depositing a second layer of aluminum within said grooves; and removing the remaining portions of said first layer of metal.
Claim 26
Independent Claim
102 words
The method comprising the steps of: providing a substrate of material having at least one surface adapted for propagation of surface waves thereupon; covering at least portions of said surface with a first layer of metal; removing portions of said first layer of metal in the form of a plurality of parallel stripes; removing portions of said substrate lying beneath the removed portions of said first layer of metal to a predetermined depth to form a plurality of grooves in said substrate; depositing a second layer of aluminum within said grooves; and removing the remaining portions of said first layer of metal.
Claim 27
Dependent Claim
11 words
The method of claim 21 wherein: said substrate comprises lithium niobate.
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) | 1981-12-18 | 1982-06-19 | 1982-12-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-12-18 | 1986-06-19 | 1986-12-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-12-18 | 1990-06-19 | 1990-12-19 | $7700.00 | Window Closed / Lapsed |