US5358927A
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US
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Growth of a,b-axis oriented pervoskite thin films
Assignee: Rutgers, The State University of New Jersey
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Filing: 1990-05-31
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Granted: 1994-10-25
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Expires: 2010-05-31
Abstract
Abstract A method, and the resulting structure, of growing a superconducting perovskite thin film of, for example YBa2Cu3O7-x. A buffer layer of, for example, the perovskite PrBa2Cu3O7-y, is grown on a crystalline (001) substrate under conditions which favor growth of a,b-axis oriented material. Then the YBa2Cu3O7-x layer is deposited on the buffer layer under changed growth conditions that favor growth of c-axis oriented material on the substrate, for example, the substrate temperature is raised by 110 DEG C. However, the buffer layer acts as a template that forces the growth of a,b-axis YBa2Cu3O7-x, which nonetheless shows a superconducting transition temperature near that of c-axis oriented films.
Inventors
- 👤 Arun Inam
- 👤 Ramamoorthy Ramesh
- 👤 Charles T. Rogers, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:50
CPC Classifications
H; H10; H10N; H10N60/00; H10N60/01; H10N60/0912; H10N60/0941; C; C30; C30B; C30B23/00; C30B23/02; C30B29/00; C30B29/10; C30B29/16; C30B29/22; C30B29/225; H10N60/0268; H10N60/0296; H10N60/0521; H10N60/0576; H10N60/0632; Y; Y10; Y10S; Y10S505/00; Y10S505/70; Y10S505/701; Y10S505/702; Y10S505/725; Y10S505/729; Y10S505/73; Y10S505/732
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
90 words
A method of growing an oriented perovskite film, comprising the steps of: depositing on a crystalline substrate a first film of a first perovskite composition under first growth conditions favoring growth of said first film as an a,b-axis oriented film; and depositing on said first film a second film of a second perovskite composition under second growth conditions favoring, in the absence of said first film, growth of said second film as a c-axis oriented film, wherein said second film grows on said first film as an a,b-axis oriented film.
Claim 2
Independent Claim
90 words
A method of growing an oriented perovskite film, comprising the steps of: depositing on a crystalline substrate a first film of a first perovskite composition under first growth conditions favoring growth of said first film as an a,b-axis oriented film; and depositing on said first film a second film of a second perovskite composition under second growth conditions favoring, in the absence of said first film, growth of said second film as a c-axis oriented film, wherein said second film grows on said first film as an a,b-axis oriented film.
Claim 3
Dependent Claim
18 words
A method as recited in claim 1, wherein said first perovskite composition differs from said second perovskite composition.
Claim 4
Dependent Claim
15 words
A method as recited in claim 2, wherein said second composition is a superconducting composition.
Claim 5
Dependent Claim
38 words
A method as recited in claim 3, wherein said first growth conditions include holding said substrate at a first temperature and said second growth conditions include holding said substrate at a second temperature different from said first temperature.
Claim 6
Dependent Claim
17 words
A method as recited in claim 4, wherein said first temperature is lower than said second temperature.
Claim 7
Dependent Claim
20 words
A method as recited in claim 3, wherein said first composition comprises PrBCO and wherein said second composition comprises YBCO.
Claim 8
Dependent Claim
38 words
A method as recited in claim 2, wherein said first growth conditions include holding said substrate at a first temperature and said second growth conditions include holding said substrate at a second temperature higher than said first temperature.
Claim 9
Dependent Claim
26 words
A method as recited in claim 7, wherein said steps of depositing said first and second films comprise pulse laser evaporation from targets onto said substrate.
Claim 10
Dependent Claim
20 words
A method as recited in claim 8, wherein said first temperature is approximately 110° C. lower than said second temperature.
Claim 11
Dependent Claim
14 words
A method as recited in claim 1, wherein said crystalline substrate comprises a perovskite.
Claim 12
Dependent Claim
15 words
A method as recited in claim 10, wherein said perovskite substrate has an (001) orientation.
Claim 13
Dependent Claim
25 words
A method as recited in claim 11, wherein said perovskite substrate has a composition chosen from the group of SrTiO 3 and LaAIO 3 .
Claim 14
Independent Claim
70 words
A method of growing an a,b-axis oriented film of a perovskite superconductor, comprising the steps of: depositing a layer of a lanthanide rare-earth barium cuprate on a surface of a crystalline material comprising an a,b-axis oriented praseodymium lanthanide rare-earth barium cuprate at deposition conditions favoring growth on a substrate of SrTiO 3 of a c-axis oriented lanthanide rare-earth barium cuprate, whereby said layer is deposited as an a,b-axis oriented layer.
Claim 15
Independent Claim
70 words
A method of growing an a,b-axis oriented film of a perovskite superconductor, comprising the steps of: depositing a layer of a lanthanide rare-earth barium cuprate on a surface of a crystalline material comprising an a,b-axis oriented praseodymium lanthanide rare-earth barium cuprate at deposition conditions favoring growth on a substrate of SrTiO 3 of a c-axis oriented lanthanide rare-earth barium cuprate, whereby said layer is deposited as an a,b-axis oriented layer.
Claim 16
Dependent Claim
20 words
A method as recited in claim 13, further comprising depositing said crystalline material on a substrate as a thin film.
Claim 17
Dependent Claim
22 words
A method as recited in claim 14, wherein said steps of depositing said layer and said crystalline material comprise pulsed laser deposition.
Claim 18
Dependent Claim
47 words
A method as recited in claim 1, wherein said a,b-axis oriented first film is oriented with one of its a-axis and b-axis perpendicular to said substrate and wherein said a,b-axis oriented second film is oriented with one of its a-axis and b-axis perpendicular to said second film.
References Cited (Backward Citations)
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EP0294285A1
Cited
US4943559A
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JPH0244782A
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