Efficient route to TlBa{sub 2}Ca{sub 2}Cu{sub 3}O{sub 9+x} thin films by metal-organic chemical vapor deposition using TlF as a thallination source
- Science and Technology Center for Superconductivity, Northwestern University, Evanston, Illinois 60208-3113 (United States)
- Materials Science Division, Science and Technology Center for Superconductivity, Argonne National Laboratory, Argonne, Illinois 60439 (United States)
Thin TlBa{sub 2}Ca{sub 2}Cu{sub 3}O{sub 9+x} films were grown on single crystal (110) LaAlO{sub 3} from metal-organic chemical-vapor deposition-derived Ba{endash}Ca{endash}Cu{endash}O{sub x} precursor films employing Ba(hfa){sub 2}{center_dot}mep, Ca(hfa){sub 2}{center_dot}tet, and Cu(dpm){sub 2} (hfa=hexafluoroacetylacetonate; dpm=dipivaloylmethanate; tet=tetraglyme; mep=methylethylpentaglyme) as the volatile metal sources. Thallination is then accomplished by annealing the precursor films in the presence of a bulk BaO+CaO+CuO+TlF source at 885{degree}C in flowing O{sub 2}. The presence of TlF is essential for nucleating the Tl-1223 phase. The resulting Tl-1223 films are nearly phase-pure, highly oriented, epitaxial by x-ray diffraction, and contain negligible fluoride by windowless energy-dispersive x-ray measurements. The films exhibit a transport measured T{sub c}=103K and J{sub c}=4.4{times}10{sup 4}A/cm{sup 2} (77 K, 0 T). Magnetic hysteresis measurements yield J{sub c}=1.9{times}10{sup 5}A/cm{sup 2} (30 K, 0.01 T) and show considerable flux pinning at low temperatures with J{sub c}=1.4{times}10{sup 5}A/cm{sup 2} (5 K, 4.5 T). {copyright} {ital 1997 American Institute of Physics.}
- Research Organization:
- ANL (Argonne National Laboratory (ANL), Argonne, IL)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- W-31-109-ENG-38
- OSTI ID:
- 538384
- Journal Information:
- Applied Physics Letters, Vol. 71, Issue 9; Other Information: PBD: Sep 1997
- Country of Publication:
- United States
- Language:
- English
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