Microstructure and microwave properties of YBCO thin films grown on MgO and SrTiO sub 3 by CVD

Journal Article · Fri Nov 01 04:00:00 EST 1991 · Journal of Materials Research; (United States)

DOI:https://doi.org/10.1557/JMR.1991.2259· OSTI ID:6190474

Young, K H; Robinson, M; Negrete, G V ^[1]; Yamashita, T ^[2]; Hirai, T ^[3]; Suzuki, H; Kurosawa, H ^[4]; Drabeck, L; Gruneer, G ^[5]

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1. Superconductor Technologies Inc., 460-F Ward Drive, Santa Barbara, California (USA)
2. Department of Electronics, Nagaoka University of Technology, Nagaoka, Niigata 940-21 (Japan)
3. Institute for Materials Research, Tohoku University, Sendai, Miyagi 980 (Japan)
4. Technological Research Center, Riken Corporation, Kumagaya 810, Saitama 360 (Japan)
5. Department of Physics, University of California-Los Angeles, Los Angeles, California (USA)

The microstructure and microwave properties of YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} thin films grown on SrTiO{sub 3} (100) and MgO (100) substrates by chemical vapor deposition have been studied. Both 100 GHz cavity measurement of surface resistance and ground plane substitution in a 5 GHz microstrip resonator show that films on SrTiO{sub 3} have better microwave properties than those on MgO. Although there are some {ital a}-axis grains and secondary phases on the surface, a large fraction of each film on SrTiO{sub 3} is epitaxial with its {ital c} axis normal to the substrate. The 100 GHz surface resistance of these films is less than copper for temperature {le}82 K, and approaches the detection limit at 10--20 K. For the films on MgO, {ital c}-axis grains of different in-plane rotation are found together with some {ital a}-axis needle-like grains. The grain boundaries are detrimental to the microwave properties, and the resulting surface resistance at 100 GHz and 10--20 K is about 20 m{Omega} higher than that of films on SrTiO{sub 3}.

• OSTI ID: 6190474
• Journal Information: Journal of Materials Research; (United States), Journal Name: Journal of Materials Research; (United States) Vol. 6:11; ISSN JMREE; ISSN 0884-2914
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202* -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
360204 -- Ceramics
Cermets
& Refractories-- Physical Properties
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
BARIUM OXIDES
CHALCOGENIDES
CHEMICAL COATING
CHEMICAL VAPOR DEPOSITION
COPPER COMPOUNDS
CRYSTAL STRUCTURE
CUPRATES
DEPOSITION
ELECTRICAL PROPERTIES
ELECTROMAGNETIC RADIATION
FILMS
FREQUENCY RANGE
GHZ RANGE
GHZ RANGE 01-100
GRAIN BOUNDARIES
HIGH-TC SUPERCONDUCTORS
MICROSTRUCTURE
MICROWAVE RADIATION
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
RADIATIONS
SUPERCONDUCTING FILMS
SUPERCONDUCTORS
SURFACE COATING
TRANSITION ELEMENT COMPOUNDS
ULTRALOW TEMPERATURE
VERY LOW TEMPERATURE
YTTRIUM COMPOUNDS
YTTRIUM OXIDES