US5873153A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making tunable thin film acoustic resonators
Assignee: Avago Technologies International Sales Pte Ltd
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Filing: 1996-08-27
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Granted: 1999-02-23
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Expires: 2016-08-27
Abstract
Abstract An acoustical resonator comprising top and bottom electrodes that sandwich a PZ layer. The resonance frequency of the acoustical resonator may be adjusted after fabrication by utilizing heating elements included in the acoustical resonator and/or by adjusting the thickness of a tuning layer. In the preferred embodiment of the present invention, the electrodes comprise Mo layers. One embodiment of the present invention is constructed on a Si 3 N 4 membrane. A second embodiment of the present invention is constructed such that it is suspended over a substrate on metallic columns. In the preferred embodiment of the present invention, the electrodes are deposited by a method that minimizes the stress in the electrodes.
Inventors
- 👤 Richard C. Ruby
- 👤 Paul Philip Merchant
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 15:30
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/15; H03H9/17; H03H9/171; H03H9/172; H03H9/174; H03H3/00; H03H3/007; H03H3/02; H03H3/04; H03H9/02; H03H9/02007; H03H9/02086; H03H9/02133; H03H9/02236; H03H9/46; H03H9/54; H03H9/58; H03H9/582; H03H9/583; H03H9/586; H03H9/588; H03H2009/02165; H03H2009/02173; H03H2009/02181; Y; Y10; Y10T; Y10T29/00; Y10T29/42
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
72 words
A method for fabricating an acoustical resonator, the method comprising: depositing a sacrificial layer on a substrate; etching vias in said sacrificial layer; depositing metal in said vias; depositing a bottom metallic layer on said sacrificial layer; depositing a PZ layer on said bottom metallic layer; depositing a top metallic layer on said PZ layer; and removing said sacrificial layer leaving a portion of said bottom metallic layer separated from said substrate.
Claim 2
Independent Claim
72 words
A method for fabricating an acoustical resonator, the method comprising: depositing a sacrificial layer on a substrate; etching vias in said sacrificial layer; depositing metal in said vias; depositing a bottom metallic layer on said sacrificial layer; depositing a PZ layer on said bottom metallic layer; depositing a top metallic layer on said PZ layer; and removing said sacrificial layer leaving a portion of said bottom metallic layer separated from said substrate.
Claim 3
Dependent Claim
11 words
The method of claim 1 wherein said PZ layer comprises AlN.
Claim 4
Dependent Claim
27 words
The method of claim 1 wherein either said bottom or said top metallic layers comprise a metal chosen from the group consisting of Mo, Ti, and W.
Claim 5
Dependent Claim
42 words
The method of claim 1, wherein the deposition conditions used in the deposition of at least one of said metallic layers are determined by measuring the deflection of a test substrate after a metallic layer is deposited thereon using said deposition conditions.
Claim 6
Dependent Claim
13 words
The method of claim 1, wherein said sacrificial layer comprises silicon and oxygen.
Claim 7
Dependent Claim
12 words
The method of claim 5, wherein said sacrificial layer comprises silicon oxide.
Claim 8
Dependent Claim
19 words
The method of claim 1, wherein at least one of said bottom and said top metallic layers comprises Mo.
Claim 9
Dependent Claim
11 words
The method of claim 4, wherein said test substrate comprises silicon.
Claim 10
Dependent Claim
26 words
The method of claim 4, wherein said deposition conditions are set to deposit said at least one of said metallic layers as a low-stress metallic layer.
Claim 11
Dependent Claim
14 words
The method of claim 9, wherein said deposition conditions determined by measuring include pressure.
Claim 12
Dependent Claim
39 words
The method of claim 4, additionally comprising setting said deposition conditions used in the deposition of said at least one of said metallic layers to deposit said at least one of said metallic layers as a low-stress metallic layer.
Claim 13
Dependent Claim
11 words
The method of claim 11, wherein said deposition conditions include pressure.
References Cited (Backward Citations)
US4320365A
Cited
US4456580A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-02-22 | 2002-08-24 | 2003-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-02-22 | 2006-08-24 | 2007-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-02-22 | 2010-08-24 | 2011-02-23 | $7700.00 | Window Closed / Lapsed |