Preparation of Tl sub 2 Ba sub 2 CaCu sub 2 O sub 8 superconducting thin films on LaAlO sub 3 substrates from metalorganic-chemical-vapor-deposition-prepared precursor films

Journal Article · Mon Sep 09 00:00:00 EDT 1991 · Applied Physics Letters; (United States)

DOI:https://doi.org/10.1063/1.105311· OSTI ID:5240291

Ladd, J A; Collins, B T; Matey, J R ^[1]; Zhao, J; Norris, P ^[2]

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1. David Sarnoff Research Center, Princeton, New Jersey (USA)
2. EMCORE Corporation, 35 Elizabeth Avenue, Somerset, New Jersey (USA)

Single phase Tl{sub 2}Ba{sub 2}CaCu{sub 2}O{sub 8} thin films have been deposited on single-crystal LaAlO{sub 3} substrates, (100) orientation, via a two-step deposition process. First, Ba-Ca-Cu-O precursor films were deposited by metalorganic chemical vapor deposition (MOCVD) using barium, calcium, and copper-tetramethyl-heptanedionate, (tmhd){sub 2}, source materials under reduced pressure in an oxygen/argon atmosphere. Substrate temperatures were between 500 and 600 {degree}C. Thallium was then incorporated by heating the films in a confined surface configuration with an unfired pellet of Tl{sub 2}Ba{sub 2}CaCu{sub 2}O{sub {ital x}} composition at 870 {degree}C for 0.1 h. The resultant films (0.5--1 {mu}m thick) showed a preferred orientation with the {ital c} axis normal to the substrate. The superconducting properties were characterized by resistance and mutual inductance versus temperature and by critical current measurements. Zero resistance temperatures as high as 98 K and {ital J}{sub {ital c}} values close to 1{times}10{sup 4} A/cm{sup 2} at 77 K were observed.

• OSTI ID: 5240291
• Journal Information: Applied Physics Letters; (United States), Vol. 59:11; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BARIUM OXIDES
CHEMICAL VAPOR DEPOSITION
SUPERCONDUCTIVITY
CALCIUM OXIDES
COPPER OXIDES
HIGH-TC SUPERCONDUCTORS
THALLIUM OXIDES
ALUMINATES
CRITICAL CURRENT
ELECTRICAL PROPERTIES
HIGH TEMPERATURE
LANTHANUM COMPOUNDS
PRECURSOR
SUPERCONDUCTING FILMS
TRANSITION TEMPERATURE
ALKALINE EARTH METAL COMPOUNDS
ALUMINIUM COMPOUNDS
BARIUM COMPOUNDS
CALCIUM COMPOUNDS
CHALCOGENIDES
CHEMICAL COATING
COPPER COMPOUNDS
CURRENTS
DEPOSITION
ELECTRIC CONDUCTIVITY
ELECTRIC CURRENTS
FILMS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
RARE EARTH COMPOUNDS
SUPERCONDUCTORS
SURFACE COATING
THALLIUM COMPOUNDS
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
360201* - Ceramics
Cermets
& Refractories- Preparation & Fabrication
360202 - Ceramics
Cermets
& Refractories- Structure & Phase Studies
360204 - Ceramics
Cermets
& Refractories- Physical Properties