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Patent US5021399A successfully refreshed from Google Patents.
US5021399A
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Spray pyrolysis process for preparing superconductive films
Assignee: Microelectronics and Computer Technology Corp
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Filing: 1989-03-10
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Granted: 1991-06-04
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Expires: 2009-03-10
Abstract
Abstract An improved method for preparing high temperature Bi-Sr-Ca-Cu-O superconductive films utilizing spray pyrolysis. The method can further include an additional annealing step to improve the electrical transport properties.
Inventors
- 👤 Hsyh-Min Hsu
- 👤 Ian Y. K. Yee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:48
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/009; C04B41/45; C04B41/50; C04B41/5072; C04B41/5074; C04B41/80; C04B41/81; C04B41/85; C23; C23C; C23C16/00; C23C16/22; C23C16/30; C23C16/40; C23C16/408; C23C16/56; H; H10; H10N; H10N60/00; H10N60/01; H10N60/0268; H10N60/0296; H10N60/0324; Y; Y10; Y10S; Y10S505/00; Y10S505/725; Y10S505/737; Y10S505/742
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
124 words
A spray pyrolysis method for preparing thin superconductive film, comprising the steps of: (a) preparing a spray pyrolysis solution comprising Bi,Sr,Ca and Cu metals in a solvent; (b) heating a substrate to a first temperature; (c) spraying said solution onto said heated substrate to form a film thereon; (d) heating said film and substrate to a second temperature of about 700°-825° C., said second temperature being higher than said first temperature; (e) heating said film and substrate to a third temperature of about 870°-890° C. to melt said film; (f) once said film and substrate reach said third temperature, further heat treating said film and substrate at a fourth temperature of about 840°-860° C.; and (g) cooling said film and substrate to ambient temperature.
Claim 2
Dependent Claim
124 words
A spray pyrolysis method for preparing thin superconductive film, comprising the steps of: (a) preparing a spray pyrolysis solution comprising Bi,Sr,Ca and Cu metals in a solvent; (b) heating a substrate to a first temperature; (c) spraying said solution onto said heated substrate to form a film thereon; (d) heating said film and substrate to a second temperature of about 700°-825° C., said second temperature being higher than said first temperature; (e) heating said film and substrate to a third temperature of about 870°-890° C. to melt said film; (f) once said film and substrate reach said third temperature, further heat treating said film and substrate at a fourth temperature of about 840°-860° C.; and (g) cooling said film and substrate to ambient temperature.
Claim 3
Dependent Claim
15 words
A method as claimed in claim 1, wherein said first temperature is about 400°-600° C.
Claim 4
Dependent Claim
15 words
A method as claimed in claim 2, wherein said first temperature is about 600° C.
Claim 5
Dependent Claim
15 words
A method as claimed in claim 1, wherein said second temperature is about 800° C.
Claim 6
Dependent Claim
15 words
A method as claimed in claim 1, wherein said third temperature is about 880° C.
Claim 7
Dependent Claim
25 words
A method as claimed in claim 1, wherein said heating step (e) includes heating in an apparatus set at a temperature between about 900°-1000° C.
Claim 8
Dependent Claim
15 words
A method as claimed in claim 6, wherein said apparatus temperature is about 950° C.
Claim 9
Dependent Claim
15 words
A method as claimed in claim 1, wherein said fourth temperature is about 855° C.
Claim 10
Dependent Claim
14 words
A method as claimed in claim 1, wherein said Bi:Sr:Ca:Cu stoichiometry is about 2:2:1:2.
Claim 11
Dependent Claim
14 words
A method as claimed in claim 1, wherein said Bi:Sr:Ca:Cu stoichiometry is about 4:3:3:4.
Claim 12
Dependent Claim
13 words
A method as claimed in claim 1, wherein said solvent is nitric acid.
Claim 13
Dependent Claim
19 words
A method as claimed in claim 1, wherein the thickness of said film is about 2 to 6 microns.
Claim 14
Dependent Claim
101 words
A spray pyrolysis method for preparing thin superconductive films, comprising the steps of: (a) preparing a spray pyrolysis solution comprising Bi, Sr, Ca and Cu metals and a fluxing agent in a solvent; (b) heating a substrate to a first temperature; (c) spraying said solution onto said heated substrate to form a film thereon; (d) heating said film and substrate to a second temperature of about 700°-825° C., said second temperature being higher than said first temperature; (e) heating said film and substrate at a third temperature of about 840°-860° C.; and (f) cooling said film and substrate to ambient temperature.
Claim 15
Dependent Claim
101 words
A spray pyrolysis method for preparing thin superconductive films, comprising the steps of: (a) preparing a spray pyrolysis solution comprising Bi, Sr, Ca and Cu metals and a fluxing agent in a solvent; (b) heating a substrate to a first temperature; (c) spraying said solution onto said heated substrate to form a film thereon; (d) heating said film and substrate to a second temperature of about 700°-825° C., said second temperature being higher than said first temperature; (e) heating said film and substrate at a third temperature of about 840°-860° C.; and (f) cooling said film and substrate to ambient temperature.
Claim 16
Dependent Claim
23 words
A method as claimed in claim 13, wherein said fluxing agent is selected from the group consisting of sodium nitrate and potassium fluoride.
Claim 17
Dependent Claim
33 words
A method as claimed in claim 13, wherein said fluxing agent is added in an amount equal to about one-tenth of the total metal ion concentration of said Bi, Sr, Ca and Cu.
Claim 18
Dependent Claim
15 words
A method as claimed in claim 13, wherein said first temperature is about 400°-600° C.
Claim 19
Dependent Claim
15 words
A method as claimed in claim 13, wherein said second temperature is about 800° C.
Claim 20
Dependent Claim
15 words
A method as claimed in claim 13, wherein said third temperature is about 850° C.
Claim 21
Dependent Claim
26 words
A method as claimed in claim 1, comprising the further step of (h) annealing said film and substrate in an inert gas of about 600°-700° C.
Claim 22
Dependent Claim
15 words
A method as claimed in claim 19, wherein said annealing temperature is about 700° C.
Claim 23
Dependent Claim
26 words
A method as claimed in claim 13, comprising the further step of (g) annealing said film and substrate in an inert gas at about 600°-700° C.
Claim 24
Dependent Claim
15 words
A method as claimed in claim 21, wherein said annealing temperature is about 700° C.
Claim 25
Dependent Claim
47 words
A spray pyrolysis method for preparing thin superconductive films, comprising the steps of: spraying a spray pyrolysis solution comprising Bi, Sr, Ca and Cu metals in a solvent onto a heated substrate to form a film thereon; and heating said film and substrate to melt said film.
Claim 26
Dependent Claim
47 words
A spray pyrolysis method for preparing thin superconductive films, comprising the steps of: spraying a spray pyrolysis solution comprising Bi, Sr, Ca and Cu metals in a solvent onto a heated substrate to form a film thereon; and heating said film and substrate to melt said film.
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