US5015618A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Laser zone melted Bi--Sr--Ca--Cu--O thick films
Assignee: Verizon Laboratories Inc
•
Filing: 1989-10-19
•
Granted: 1991-05-14
•
Expires: 2009-10-19
Abstract
Abstract A method for preparing a highly aligned thick film of superconducting bismuth strontium calcium copper oxide ceramic material to improve its critical current density. A film about 5-200 μm thick of bismuth strontium calcium copper oxide is deposited on a suitable substrate. The ratios of Bi:(Sr, Ca):Cu in the film are about 2:3:2 to 2:4:3. A laser beam is translated over the deposited film at a rate of about 0.2-15 cm/hr while the film is held at a temperature of about 500°-950° C. The beam is about 0.01-0.50 cm wide along the direction of translation, and provides about 0.2-10W of optical power to the film. The temperature and the beam translation rate, width, and optical power are selected to permit zone melting and resolidification of the film to form the highly aligned thick film of superconducting bismuth strontium calcium copper oxide ceramic material. The J c may, if desired, be further improved by annealing the resolidified film at about 900°-965° C. for about 1-300 hr.
Inventors
- 👤 Mark Levinson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:38
CPC Classifications
C; C30; C30B; C30B29/00; C30B29/10; C30B29/16; C30B29/22; C30B29/225; C30B13/00; H; H10; H10N; H10N60/00; H10N60/01; H10N60/0268; H10N60/0296; H10N60/0548; Y; Y10; Y10S; Y10S428/00; Y10S428/922; Y10S428/9265; Y10S428/93; Y10S505/00; Y10S505/725; Y10S505/729
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
152 words
A method for preparing a highly aligned thick film of superconducting bismuth strontium calcium copper oxide ceramic material comprising the steps of: depositing on a suitable substrate a film about 5-200 μm thick of bismuth strontium calcium copper oxide wherein the ratios of Bi:(Sr, Ca):Cu are about 2:3:2 to 2:4:3; and translating a laser beam over said deposited film in a direction relative to said deposited film and at a rate of about 0.2-15 cm/hr while said deposited film is held at a temperature of about 500°-950° C., wherein said beam is about 0.01-0.50 cm wide along said direction and provides about 0.2-10 W of optical power to said deposited film, and wherein said temperature and said beam translation rate, width, and optical power are selected to permit zone melting and resolidification of said deposited film to form said highly aligned thick film of superconducting bismuth strontium calcium copper oxide ceramic material.
Claim 2
Independent Claim
152 words
A method for preparing a highly aligned thick film of superconducting bismuth strontium calcium copper oxide ceramic material comprising the steps of: depositing on a suitable substrate a film about 5-200 μm thick of bismuth strontium calcium copper oxide wherein the ratios of Bi:(Sr, Ca):Cu are about 2:3:2 to 2:4:3; and translating a laser beam over said deposited film in a direction relative to said deposited film and at a rate of about 0.2-15 cm/hr while said deposited film is held at a temperature of about 500°-950° C., wherein said beam is about 0.01-0.50 cm wide along said direction and provides about 0.2-10 W of optical power to said deposited film, and wherein said temperature and said beam translation rate, width, and optical power are selected to permit zone melting and resolidification of said deposited film to form said highly aligned thick film of superconducting bismuth strontium calcium copper oxide ceramic material.
Claim 3
Dependent Claim
22 words
A method in accordance with claim 1 wherein the laser beam translating step is carried out in air or an oxidizing atmosphere.
Claim 4
Dependent Claim
24 words
A method in accordance with claim 1 further comprising the step of annealing said resolidified film at about 900°-965° C. for about 1-300 hr.
Claim 5
Dependent Claim
20 words
A method in accordance with claim 2 wherein the annealing step is carried out in air or an oxidizing atmosphere.
Claim 6
Independent Claim
163 words
A method for preparing a highly aligned thick film of superconducting bismuth strontium calcium copper oxide ceramic material comprising the steps of: depositing on a MgO substrate a film about 20 μm thick of bismuth strontium calcium copper oxide wherein the ratios of Bi:Sr:Ca:Cu are about 2:2:2:3; and translating a laser beam over said deposited film in a direction relative to said deposited film and at a rate of about 0.2-3.0 cm/hr while said deposited film is held at a temperature of about 500°-950° C., wherein said beam is about 0.01-0.50 cm wide along said direction of translation, and provides about 2.0-2.4 W of optical power to said deposited film, and wherein said temperature and said beam translation rate, width, and optical power are selected to permit zone melting and resolidification of said deposited film to form said highly aligned thick film of superconducting bismuth strontium calcium copper oxide ceramic material; annealing said resolidified film at about 900°-965° C. for about 12-137 hr.
Claim 7
Independent Claim
163 words
A method for preparing a highly aligned thick film of superconducting bismuth strontium calcium copper oxide ceramic material comprising the steps of: depositing on a MgO substrate a film about 20 μm thick of bismuth strontium calcium copper oxide wherein the ratios of Bi:Sr:Ca:Cu are about 2:2:2:3; and translating a laser beam over said deposited film in a direction relative to said deposited film and at a rate of about 0.2-3.0 cm/hr while said deposited film is held at a temperature of about 500°-950° C., wherein said beam is about 0.01-0.50 cm wide along said direction of translation, and provides about 2.0-2.4 W of optical power to said deposited film, and wherein said temperature and said beam translation rate, width, and optical power are selected to permit zone melting and resolidification of said deposited film to form said highly aligned thick film of superconducting bismuth strontium calcium copper oxide ceramic material; annealing said resolidified film at about 900°-965° C. for about 12-137 hr.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-05-13 | 1994-11-12 | 1995-05-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-05-13 | 1998-11-12 | 1999-05-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-05-13 | 2002-11-12 | 2003-05-14 | $7700.00 | Window Closed / Lapsed |