US4677336A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Piezoelectric transducer and process for its production
Assignee: Hitachi Ltd
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Filing: 1986-01-31
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Granted: 1987-06-30
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Expires: 2006-01-31
Abstract
Abstract A piezoelectric transducer made from a piezoelectric thin film based on lead titanate (PbTiO 3 ): comprising a substrate having sawtooth profile gratings formed on the surface by anisotropic etching; a platinum layer formed by graphoepitaxy method on the substance; a piezoelectric thin film formed on the platinum layer; and an upper electrode layer. Although platinum shows (111) orientation, a (100)-oriented platinum film can be obtained by depositing platinum on said substrate having the gratings by graphoepitaxy. A c-axis-oriented piezoelectric film of excellent piezoelectricity can be formed on this platinum film.
Inventors
- 👤 Keiko Kushida
- 👤 Hiroshi Takeuchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 07:35
CPC Classifications
H; H04; H04R; H04R17/00; H10; H10N; H10N30/00; H10N30/01; H10N30/06; H10N30/07; H10N30/074; H10N30/076; H10N30/704; H10N30/706; H10N30/04; H10N30/045; H10N30/80; H10N30/85; H10N30/853; H10N30/8548
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
55 words
A piezoelectric transducer comprising a substrate having sawtooth profile gratings on the main surface; a first metal layer comprising a face-centered cubic metal material showing (111) orientation on smooth surface; a piezoelectric film formed on said first metal layer and comprising a perovskite-type piezoelectric material; and a second metal layer formed on said piezoelectric film.
Claim 2
Dependent Claim
55 words
A piezoelectric transducer comprising a substrate having sawtooth profile gratings on the main surface; a first metal layer comprising a face-centered cubic metal material showing (111) orientation on smooth surface; a piezoelectric film formed on said first metal layer and comprising a perovskite-type piezoelectric material; and a second metal layer formed on said piezoelectric film.
Claim 3
Dependent Claim
26 words
A piezoelectric transducer according to claim 1, wherein the gratings on the main surface of said substrate have an angle of intersection of slope of 70.5°.
Claim 4
Dependent Claim
18 words
A piezoelectric transducer according to claim 1, wherein said gratings have a pitch of 0.6 μm or below.
Claim 5
Dependent Claim
15 words
A piezoelectric transducer according to claim 1, wherein said first metal layer comprises platinum (Pt).
Claim 6
Dependent Claim
19 words
A piezoelectric transducer according to claim 1, wherein said piezoelectric film comprises a piezoelectric material based on lead titanate.
Claim 7
Dependent Claim
15 words
A piezoelectric transducer according to claim 1, wherein said substrate comprises a silicon single crystal.
Claim 8
Dependent Claim
118 words
An array piezoelectric transducer in which a plurality of transducer elements are set in array, comprising a substrate having sawtooth profile gratings on that specified regions of the main surface which coincide with the transducer elements; a first metal layer formed on the main surface of said substrate, comprising a face-centered cubic metal showing (111) orientation on smooth surface, and serving as an electrode common to the transducer elements of said transducer; a piezoelectric film formed on said first metal layer and comprising a perovskite-type piezoelectric material; and a second metal layer formed on said specified regions on said piezoelectric film wherein the part in each of the regions serves as an electrode for each of the elements.
Claim 9
Dependent Claim
118 words
An array piezoelectric transducer in which a plurality of transducer elements are set in array, comprising a substrate having sawtooth profile gratings on that specified regions of the main surface which coincide with the transducer elements; a first metal layer formed on the main surface of said substrate, comprising a face-centered cubic metal showing (111) orientation on smooth surface, and serving as an electrode common to the transducer elements of said transducer; a piezoelectric film formed on said first metal layer and comprising a perovskite-type piezoelectric material; and a second metal layer formed on said specified regions on said piezoelectric film wherein the part in each of the regions serves as an electrode for each of the elements.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1990-06-29 | 1990-12-29 | 1991-06-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-06-29 | 1994-12-29 | 1995-06-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-06-29 | 1998-12-29 | 1999-06-30 | $7700.00 | Window Closed / Lapsed |