US4590399A
Expired / Lapsed
US
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Superlattice piezoelectric devices
Assignee: ExxonMobil Technology and Engineering Co
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Filing: 1984-10-09
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Granted: 1986-05-20
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Expires: 2004-10-09
Abstract
Abstract Piezoelectric transducers and oscillators made from amorphous superlattice structures are disclosed. These materials have large built-in fields necessary for piezoelectricity but they are materials which can be deposited at low temperatures onto virtually any substrate.
Inventors
- 👤 Charles B. Roxlo
- 👤 Peter D. Persans
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:05
CPC Classifications
H; H10; H10D; H10D48/00; H10D48/50; H10N; H10N30/00; H10N30/80; H10N30/85; H10N30/853; Y; Y10; Y10S; Y10S310/00; Y10S310/80
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
84 words
A piezoelectric device whose active material which exhibits the piezoelectric effect comprises a superlattice which includes a multilayered material wherein layers 1, 3, 5 . . . have the same compressibility and layers 2, 4, 6 . . . have the same compressibility but different from that of layers 1, 3, 5 . . . and wherein electric fields exist across each layer, said electric fields being perpendicular to the interface between layers with the sign of the electric field alternating between adjacent layers.
Claim 2
Dependent Claim
84 words
A piezoelectric device whose active material which exhibits the piezoelectric effect comprises a superlattice which includes a multilayered material wherein layers 1, 3, 5 . . . have the same compressibility and layers 2, 4, 6 . . . have the same compressibility but different from that of layers 1, 3, 5 . . . and wherein electric fields exist across each layer, said electric fields being perpendicular to the interface between layers with the sign of the electric field alternating between adjacent layers.
Claim 3
Dependent Claim
30 words
The piezoelectric device of claim 1 whose active material which exhibits the piezoelectric effect comprises a superlattice which includes a multilayered material where a lattice mismatch exists between adjacent layers.
Claim 4
Dependent Claim
10 words
The device of claim 1 wherein said superlattice is amorphous.
Claim 5
Dependent Claim
10 words
The device of claim 2 wherein said superlattice is amorphous.
Claim 6
Dependent Claim
15 words
The device of claim 3 wherein the electric fields are greater than 10 4 volts/cm.
Claim 7
Dependent Claim
18 words
The device of claim 4 wherein the lattice mismatch is greater than 1 part in 10 3 .
Claim 8
Dependent Claim
33 words
The piezoelectric device whose active material which exhibits the piezoelectric effect comprises an amorphous superlattice wherein charge is assymetrically distributed at the interfaces thereby causing electrical fields between adjacent layers of said superlattice.
Claim 9
Dependent Claim
33 words
The piezoelectric device whose active material which exhibits the piezoelectric effect comprises an amorphous superlattice wherein charge is assymetrically distributed at the interfaces thereby causing electrical fields between adjacent layers of said superlattice.
Claim 10
Dependent Claim
15 words
The device of claim 7 wherein said charge is within 20 Å of said interfaces.
Claim 11
Dependent Claim
16 words
The device of claim 7 wherein said charge is greater than 10 12 electrons/cm 2 .
Claim 12
Dependent Claim
63 words
A piezoelectric device whose active material which exhibits the piezoelectric effect comprises an amorphous superlattice which includes a multilayered material wherein electric fields exist across each layer, said electric fields being perpendicular to the interface between layers with the sign of the electric field alternating between adjacent layers, wherein said superlattice includes layers of a-Si:H/a-SiN x :H or layers of a-Si:H/a-SiC x :H.
Claim 13
Dependent Claim
63 words
A piezoelectric device whose active material which exhibits the piezoelectric effect comprises an amorphous superlattice which includes a multilayered material wherein electric fields exist across each layer, said electric fields being perpendicular to the interface between layers with the sign of the electric field alternating between adjacent layers, wherein said superlattice includes layers of a-Si:H/a-SiN x :H or layers of a-Si:H/a-SiC x :H.
Claim 14
Dependent Claim
43 words
A piezoelectric device whose active material which exhibits the piezoelectric effect comprises an amorphous superlattice which includes a multilayered material where a lattice mismatch exists between adjacent layers, wherein said superlattice includes layers of a-Si:H/a-SiN x :H or layers of a-SiH/a-SiC x :H.
Claim 15
Dependent Claim
43 words
A piezoelectric device whose active material which exhibits the piezoelectric effect comprises an amorphous superlattice which includes a multilayered material where a lattice mismatch exists between adjacent layers, wherein said superlattice includes layers of a-Si:H/a-SiN x :H or layers of a-SiH/a-SiC x :H.
References Cited (Backward Citations)
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