Phase Relations in the Ba-Y-Cu-O Films on SrTiO₃ for the Ex Situ BaF₂ Process

Journal Article · Mon Jan 01 04:00:00 EST 2007 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.2713124· OSTI ID:931502

Wong-Ng, W. ^[1]; Levin, I. ^[1]; Otani, M. ^[1]; Vaudin, M. ^[1]; Cook, L. P. ^[1]; Cline, J. ^[1]; Feenstra, Roeland ^[2]; Holesinger, T. G. ^[3]

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1. National Institute of Standards and Technology (NIST)
2. ORNL
3. Los Alamos National Laboratory (LANL)

In situ x-ray diffraction was used to establish the phase relations in high-{Tc} superconductor Ba-Y-Cu-O films grown on SrTiO{sub 3} through the ex situ BaF{sub 2} process. These relations differ from bulk equilibrium phase assemblages in the BaO-Y{sub 2}O{sub 3}-CuO{sub x} system. In particular, BaY2CuO5 (the 'green phase'), a common impurity phase in bulk processing, is absent in the films. Because of the absence of this green phase, the compositional stability field of Ba{sub 2}YCu{sub 3}O{sub 6+x} expands considerably as compared to that of the bulk system, resulting in the tie lines Ba{sub 2}YCu{sub 3}O{sub 6+x}-Y{sub 2}O{sub 3} and Ba{sub 2}YCu{sub 3}O{sub 6+x}-Y{sub 2}Cu{sub 2}O{sub 5}.

• Research Organization: Oak Ridge National Laboratory (ORNL)
• Sponsoring Organization: OE USDOE - Office of Electric Transmission and Distribution
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 931502
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Vol. 90; ISSN 0003-6951; ISSN APPLAB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BARIUM OXIDES
COPPER OXIDES
HIGH-TC SUPERCONDUCTORS
PHASE STUDIES
STRONTIUM OXIDES
SUBSTRATES
TITANIUM OXIDES
YTTRIUM OXIDES