US4933318A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Plasma etch of masked superconductor film
Assignee: US Philips Corp
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Filing: 1988-12-12
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Granted: 1990-06-12
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Expires: 2008-12-12
Abstract
Abstract A method of manufacturing a thin film of an oxidic superconducting material in accordance with a pattern, in which a pattern is manufactured by means of etching using reactive ions and a mask of aluminium oxide or silicon oxide, said method enabling patterns having line widths smaller than 2 μm to be manufactured with great accuracy without influencing the composition of the superconducting thin film in such a manner that the superconducting properties deteriorate.
Inventors
- 👤 Maritza G. J. Heijman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:32
CPC Classifications
H; H10; H10N; H10N60/00; H10N60/01; H10N60/0268; H10N60/0661; H10N60/0688; H10N60/0744; H10N60/80; H10N60/85; H10N60/855; H10N60/857; Y; Y10; Y10S; Y10S505/00; Y10S505/725; Y10S505/728
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
191 words
A method of manufacturing a patterned thin film of a rare-earth-metal, alkali-earth-metal, copper oxide superconducting material on an electrically insulating substrate said method comprising: (a) depositing a thin film of a rare-earth-metal, alkali-earth-metal, copper oxide superconducting material on an electrically insulating substrate, (b) depositing an inorganic masking layer on said thin film of superconducting material wherein said inorganic masking layer is manufactured from aluminum oxide and/or silicon oxide, (c) depositing an organic photoresist on said inorganic masking layer, (d) forming a patterned resist from said organic photoresist layer, (e) etching said inorganic masking layer according to the organic photoresist pattern, in a plasma in an atmosphere consisting essentially of a mixture of trifluoromethane and argon, while employing said patterned organic photoresist as a mask, (f) removing said organic photoresist, (g) etching said thin material of superconducting film, according to the inorganic masking layer, in a chlorine containing plasma wherein said chlorine containing plasma comprises Cl 2 and/or HCl while employing said etched inorganic masking layer as a mask, and (h) removing said etched inorganic masking layer with a plasma in an atmosphere consisting essentially of a mixture of trifluoromethane and argon.
Claim 2
Independent Claim
191 words
A method of manufacturing a patterned thin film of a rare-earth-metal, alkali-earth-metal, copper oxide superconducting material on an electrically insulating substrate said method comprising: (a) depositing a thin film of a rare-earth-metal, alkali-earth-metal, copper oxide superconducting material on an electrically insulating substrate, (b) depositing an inorganic masking layer on said thin film of superconducting material wherein said inorganic masking layer is manufactured from aluminum oxide and/or silicon oxide, (c) depositing an organic photoresist on said inorganic masking layer, (d) forming a patterned resist from said organic photoresist layer, (e) etching said inorganic masking layer according to the organic photoresist pattern, in a plasma in an atmosphere consisting essentially of a mixture of trifluoromethane and argon, while employing said patterned organic photoresist as a mask, (f) removing said organic photoresist, (g) etching said thin material of superconducting film, according to the inorganic masking layer, in a chlorine containing plasma wherein said chlorine containing plasma comprises Cl 2 and/or HCl while employing said etched inorganic masking layer as a mask, and (h) removing said etched inorganic masking layer with a plasma in an atmosphere consisting essentially of a mixture of trifluoromethane and argon.
Claim 3
Dependent Claim
41 words
A method as claimed in claim 1 wherein the oxidic superconducting material comprises YBa 2 Cu 3 O 7- α-8 F.sub.α, wherein α has a value of from 0 to 1 and δ has a value of from 0.1 to 0.5.
Claim 4
Dependent Claim
22 words
A method of claim 1 wherein the patterned organic photoresist is formed by locally irradiating irradiation-sensitive organic resist and subsequently developing it.
Claim 5
Dependent Claim
20 words
The method of claim 3 wherein the patterned organic photoresist is removed by means of a plasma treatment in oxygen.
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) | 1993-06-11 | 1993-12-11 | 1994-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-11 | 1997-12-11 | 1998-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-11 | 2001-12-11 | 2002-06-12 | $7700.00 | Window Closed / Lapsed |