Improvement in the properties of high T sub c films fabricated in situ by laser ablation of YBa sub 2 Cu sub 3 O sub 7 -Ag targets

Journal Article · Mon Jan 13 04:00:00 EST 1992 · Applied Physics Letters; (United States)

DOI:https://doi.org/10.1063/1.106954· OSTI ID:5526984

Singh, R K; Bhattacharya, D ^[1]; Tiwari, P; Narayan, J ^[2]; Lee, C B ^[3]

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1. Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611-2066 (United States)
2. Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695-7916 (United States)
3. Department of Electrical Engineering, North Carolina A T State University, Greensboro, North Carolina 27411 (United States)

We have studied the microstructural and superconducting properties of YBa{sub 2}Cu{sub 3}O{sub 7} films fabricated by pulsed laser evaporation of YBa{sub 2}Cu{sub 3}O{sub 7}-Ag targets, containing approximately 30% by weight of silver. The films produced by excimer laser evaporation/ablation of YBa{sub 2}Cu{sub 3}O{sub 7}-Ag targets were found to possess better superconducting and microstructural properties than films prepared under the same conditions from bulk YBa{sub 2}Cu{sub 3}O{sub 7} targets. YBa{sub 2}Cu{sub 3}O{sub 7} films deposited on yttria stabilized zirconia (YSZ) substrates from YBa{sub 2}Cu{sub 3}O{sub 7}-Ag targets at 650 {degree}C showed helium ion channeling yields of approximately 9%--12%, while films deposited from YBa{sub 2}Cu{sub 3}O{sub 7} targets had channeling yields in the range of 18%--25%. The critical current density of YBa{sub 2}Cu{sub 3}O{sub 7}Ag{sub {ital x} }films on YSZ substrates had values of approximately 1.8{times}10{sup 6} A/cm{sup 2} at 77 K which corresponds to approximately an 80% improvement from the values obtained from films deposited from cold pressed YBa{sub 2}Cu{sub 3}O{sub 7} targets. Based on the structural and chemical information, it appears that two effects play a major role in improving the superconducting properties of laser ablated thin films made from silver composite superconductor targets (i) improved evaporation characteristics of the targets due to silver incorporation and (ii) the catalyst effect of silver in stabilizing the superconducting phase and enhancing grain growth.

• OSTI ID: 5526984
• Journal Information: Applied Physics Letters; (United States), Journal Name: Applied Physics Letters; (United States) Vol. 60:2; ISSN APPLA; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202* -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
360207 -- Ceramics
Cermets
& Refractories-- Superconducting Properties-- (1992-)
ALKALINE EARTH METAL COMPOUNDS
ALLOYS
BARIUM COMPOUNDS
BARIUM OXIDES
CATALYTIC EFFECTS
CHALCOGENIDES
COPPER COMPOUNDS
CRITICAL CURRENT
CRYSTAL GROWTH
CRYSTAL STRUCTURE
CUPRATES
CURRENT DENSITY
CURRENTS
ELECTRIC CONDUCTIVITY
ELECTRIC CURRENTS
ELECTRICAL PROPERTIES
HIGH-TC SUPERCONDUCTORS
LASER-PRODUCED PLASMA
MICROSTRUCTURE
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
PLASMA
SILVER ADDITIONS
SILVER ALLOYS
SUPERCONDUCTIVITY
SUPERCONDUCTORS
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
YTTRIUM OXIDES