Patent EP0727832A1 successfully refreshed from Google Patents.
EP0727832A1
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EP
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Piezoelectric thin film, method for producing the same, and ink jet recording head
Assignee: Seiko Epson Corp
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Filing: 1996-02-20
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Granted: —
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Expires: 2016-02-20
Abstract
Abstract A piezoelectric thin film having good properties, for example, a high dielectric constant and a high piezoelectric strain constant is disclosed. Further, a method for producing the same which does not suffer from cracks at the time of annealing is also disclosed. The piezoelectric thin film according to the present invention comprises a thin film with the average grain area of crystal grains observed on the surface of the thin film being not less than 0.1 µm 2 , the thin film having no multilayer structure in its cross section. The method for producing the piezoelectric thin film is based on a sol-gel process and comprises the steps of: coating a substrate with a sol composition comprising a sol, of a metal component for constituting a piezoelectric film, and a polymer compound and then drying the coating to form a film; pre-sintering the film to form a porous thin film of gel comprising an amorphous metal oxide; pre-annealing the porous thin film of gel to convert the film to a film of a crystalline metal oxide; repeating the steps at least once to form laminated films of a crystalline metal oxide; and annealing the films thus prepared to grow crystal grains of perovskite type in the film into a larger size.
Inventors
- 👤 Satoru C/O Seiko Epson Corporation Miyashita
- 👤 Masakazu C/O Seiko Epson Corporation Shinozuka
- 👤 Tetsushi C/O Seiko Epson Corporation Takahashi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 01:55
CPC Classifications
H; H10; H10N; H10N30/00; H10N30/01; H10N30/07; H10N30/074; H10N30/077; H10N30/078; H10N30/80; H10N30/85; H10N30/853; H10N30/8548; H10N30/8554; Y; Y10; Y10S; Y10S310/00; Y10S310/80; Y10T; Y10T29/00; Y10T29/42
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
43 words
A piezoelectric thin film comprising a thin film with the average grain area of crystal grains observed on the surface of the thin film being not less than 0.1 µm 2 , the thin film having no multilayer structure in its cross section.
Claim 2
Dependent Claim
24 words
The piezoelectric thin film according to claim 1, wherein the average grain area of the crystal grains is 0.5 to 50 µm 2 .
Claim 3
Dependent Claim
22 words
The piezoelectric thin film according to claim 1 or 2, wherein the thin film has a thickness of 0.5 to 20 µm.
Claim 4
Dependent Claim
24 words
A thin film piezoelectric device comprising a piezoelectric thin film according to any one of claims 1 to 3 sandwiched between two electrode films.
Claim 5
Independent Claim
131 words
A method for preparing a piezoelectric thin film by a sol-gel process, comprising the steps of: a) coating a substrate with a sol composition comprising a sol, of a metal component for constituting a piezoelectric film, and a polymer compound and then drying the coating to form a film; b) pre-sintering the film to form a porous thin film of gel comprising an amorphous metal oxide; c) pre-annealing the porous thin film of gel to bring the film to a film formed of a crystalline metal oxide; d) repeating the steps a), b), and c) at least once to form laminated films of a crystalline medal oxide; and e) annealing the films prepared in the step d) to grow crystal grains of perovskite type in the film into a larger size.
Claim 6
Independent Claim
152 words
A method for preparing a piezoelectric thin film by a sol-gel process, comprising the steps of: a) coating a substrate with a sol composition comprising a sol, of a metal component for constituting a piezoelectric film, and a polymer compound and then drying the coating to form a film; b) pre-sintering the film to form a porous thin film of gel comprising an amorphous metal oxide; f) repeating the steps a) and b) at least once to form laminated layers of porous thin films comprising an amorphous metal oxide; c') pre-annealing the laminated layers of thin film to convert the layers to a film of a crystalline metal oxide; d') repeating the steps f) and c') at least once to form laminated films of a crystalline metal oxide; and e') annealing the films prepared in the step d') to grow crystal grains of perovskite type in the film into a larger size.
Claim 7
Dependent Claim
37 words
The method for preparing a piezoelectric thin film according to claim 5 or 6, wherein the pre-annealing in the step c) or c') is carried out at a temperature in the range of from 400 to 800°C.
Claim 8
Dependent Claim
37 words
The method for preparing a piezoelectric thin film according to claim 5 or 6, wherein the annealing in the step e) or e') is carried out at a temperature in the range of from 600 to 1200°C.
Claim 9
Dependent Claim
37 words
The method for preparing a piezoelectric thin film according to claim 5 or 6, wherein the annealing in the step e) or e') is carried out at a temperature in the range of from 800 to 1000°C.
Claim 10
Dependent Claim
66 words
The method for preparing a piezoelectric thin film according to claim 5 or 6, wherein the pre-annealing in the step c) or c') is carried out in two stages, the first stage of which is carried out at a temperature in the range of from 400 to 600°C with the second stage being carried out at a temperature in the range of from 600 to 800°C.
Claim 11
Dependent Claim
66 words
The method for preparing a piezoelectric thin film according to claim 5 or 6, wherein the annealing in the step e) or e') is carried out in two stages, the first stage of which is carried out at a temperature in the range of from 600 to 800°C with the second stage being carried out at a temperature in the range of from 800 to 1000°C.
Claim 12
Dependent Claim
45 words
The method for preparing a piezoelectric thin film according to claim 5 or 6, wherein the thickness of the porous thin film formed in the step b) or the thickness of the porous thin film newly formed in the step f)is 0.01 to 1 µm.
Claim 13
Dependent Claim
45 words
The method for preparing a piezoelectric thin film according to claim 5 or 6, wherein the laminate of a crystalline metal oxide prepared in the step d) or d') is patterned into a thin film piezoelectric device form prior to the step e) or e').
Claim 14
Dependent Claim
56 words
A piezoelectric thin film obtainable by a method according to any one of claims 5 to 13, comprising a thin film with the average grain area of crystal grains observed on the surface of the thin film being not less than 0.1 µm 2 , the thin film having no multilayer structure in its cross section.
Claim 15
Dependent Claim
24 words
An ink jet recording head comprising, as a transducer, a piezoelectric thin film according to any one of claims 1 to 4 and 14.
References Cited (Backward Citations)
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