New hybrid physical vapor deposition/organometallic chemical vapor deposition route to high T sub c superconducting Tl-Ba-Ca-Cu-O thin films
- Northwestern University, Evanston, Illinois 60208 (US)
High {ital T}{sub {ital c}} superconducting Tl-Ba-Ca-Cu-O thin films have been prepared by a novel hybrid technique that combines electron beam evaporation with organometallic chemical vapor deposition (OMCVD). Multilayer thin films of Ba-Ca-Cu-O are prepared by sequential evaporation of BaF{sub 2}, CaF{sub 2}, and Cu sources onto single-crystal MgO (100) or yttria-stabilized zirconia substrates followed by annealing in a water vapor-saturated oxygen atmosphere. Thallium is then incorporated in these films in either of two ways: (1) OMCVD using thallium(cyclopentadienide) as the source or (2) vapor diffusion using bulk Tl-Ba-Ca-Cu-O superconductor as the source. The resultant films are single phase, consisting predominantly of Tl{sub 1}Ba{sub 2}Ca{sub 2}Cu{sub 3}O{sub {ital x}} with crystallite Cu-O planes preferentially oriented parallel to the substrate surface. Resistivity measurements indicate superconducting onset temperatures above 120 K with zero resistance by 104 K. By eliminating the water vapor in the initial anneal, fluoride (originating from the Ba and Ca sources) may be retained in the film. Upon T1 incorporation, this promotes formation of the Tl{sub 1}Ba{sub 2}Ca{sub 1}Cu{sub 2}O{sub {ital x}} phase with preferential crystallite {ital c}-axis orientation perpendicular to the substrate surface.
- OSTI ID:
- 7246955
- Journal Information:
- Applied Physics Letters; (USA), Journal Name: Applied Physics Letters; (USA) Vol. 55:26; ISSN APPLA; ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
360201* -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
360204 -- Ceramics
Cermets
& Refractories-- Physical Properties
656100 -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALKALINE EARTH METAL COMPOUNDS
ANNEALING
BARIUM COMPOUNDS
BARIUM FLUORIDES
BARIUM OXIDES
CALCIUM COMPOUNDS
CALCIUM FLUORIDES
CALCIUM HALIDES
CALCIUM OXIDES
CHALCOGENIDES
CHEMICAL COATING
CHEMICAL VAPOR DEPOSITION
COATINGS
COPPER
COPPER COMPOUNDS
COPPER OXIDES
CRYSTAL-PHASE TRANSFORMATIONS
DATA
DEPOSITION
ELEMENTS
EXPERIMENTAL DATA
FABRICATION
FILMS
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
HEAT TREATMENTS
INFORMATION
LOW TEMPERATURE
MAGNESIUM COMPOUNDS
MAGNESIUM OXIDES
METALS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANOMETALLIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
SUPERCONDUCTING FILMS
SURFACE COATING
THALLIUM COMPOUNDS
THALLIUM OXIDES
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
TRANSITION TEMPERATURE
VAPOR DEPOSITED COATINGS
ZIRCONIUM COMPOUNDS
ZIRCONIUM OXIDES