Pulsed laser deposition of thin superconducting films of Ho/sub 1/Ba/sub 2/Cu/sub 3/O/sub 7-//sub x/ and Y/sub 1/Ba/sub 2/Cu/sub 3/O/sub 7-//sub x/

Journal Article · Mon Oct 31 23:00:00 EST 1988 · J. Mat. Res.; (United States)

OSTI ID:6747041

Geohegan, D B; Mashburn, D N; Culbertson, R J; Pennycook, S J; Budai, J D; Valiga, R E; Sales, B C; Lowndes, D H; Boatner, L A; Sonder, E; others, and

Thin films of Ho/sub 1/Ba/sub 2/Cu/sub 3/O/sub 7-//sub x/ and Y/sub 1/Ba/sub 2/Cu/sub 3/O/sub 7-//sub x/ were deposited on SrTiO/sub 3/ and Al/sub 2/O/sub 3/ substrates by pulsed laser deposition of high-T/sub c/ bulk superconductor pellets in vacuum. Following annealing in O/sub 2/ at 800--900 /sup 0/C the films were superconducting with typical T/sub c/ (50%) = 89 K and transition widths of 10 K. Rutherford backscattering spectrometry (RBS) and secondary ion mass spectrometry (SIMS) were utilized to study the stoichiometry of the as-deposited films for laser energy densities between 0.11 and 4.5 J cm/sup -2/. The films were deficient in holmium and yttrium for energy densities below 0.6 and 0.4 J cm/sup -2/, respectively. The films were stoichiometric for fluences above 0.6 J cm/sup -2/. In addition, preliminary time dependence and spectroscopic observations of the laser-produced plasma are presented. The results indicate an ablation mechanism that at high energy densities preserves stoichiometry. TEM and x-ray characterization of annealed, superconducting Ho/sub 1/Ba/sub 2/Cu/sub 3/O/sub 7-//sub x/ films on (100) SrTiO/sub 3/ showed mixed regions of epitaxially oriented 1:2:3 material with either the c axis or a axis oriented along the surface normal. The a-axis-oriented material grew preferentially in the films with b, c, twinning. Y/sub 1/Ba/sub 2/Cu/sub 3/O/sub 7-//sub x/

• Research Organization: Solid State Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6056
• OSTI ID: 6747041
• Journal Information: J. Mat. Res.; (United States), Journal Name: J. Mat. Res.; (United States) Vol. 3:6; ISSN JMREE
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360201* -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
360202 -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
656100 -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
BARIUM OXIDES
CHALCOGENIDES
CHEMICAL COMPOSITION
COPPER COMPOUNDS
COPPER OXIDES
CRYSTAL STRUCTURE
DEPOSITION
ELECTROMAGNETIC RADIATION
EVAPORATION
FILMS
HOLMIUM COMPOUNDS
HOLMIUM OXIDES
LASER RADIATION
LASER SPECTROSCOPY
MICROSTRUCTURE
OXIDES
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
RADIATIONS
RARE EARTH COMPOUNDS
SPECTROSCOPY
STOICHIOMETRY
SUBSTRATES
SUPERCONDUCTING FILMS
TRANSITION ELEMENT COMPOUNDS
VACUUM EVAPORATION
YTTRIUM COMPOUNDS
YTTRIUM OXIDES