Molecular-beam epitaxy and deposition of high-T/sub c/ superconductors

Journal Article · Tue Mar 01 04:00:00 EST 1988 · J. Vac. Sci. Technol., B; (United States)

DOI:https://doi.org/10.1116/1.584334· OSTI ID:5311324

Hellman, E S; Schlom, D G; Missert, N; Char, K; Harris, Jr, J S; Beasley, M R; Kapitulnik, A; Geballe, T H; Eckstein, J N; Weng, S; others, and

We have grown thin, highly oriented, polycrystalline DyBa/sub 2/Cu/sub 3/O/sub 7-//sub x/ films using molecular-beam epitaxy (MBE) techniques that show the onset of superconductivity at temperatures above 90 K and complete transitions at temperatures as high as 87 K. These films have critical current densities as high as 5 x 10/sup 5/ A/cm/sup 2/ at 4.2 K. Films were grown in a modified Varian 360 MBE machine using effusion sources containing the metal constituents, along with a gaseous oxygen source. The early stages of deposition were monitored with reflection high-energy electron diffraction (RHEED). The best films were obtained on SrTiO/sub 3/ substrates at substrate temperatures of 600--750 /sup 0/C. At these temperatures, the initial stage of growth is dominated by epitaxy of copper islands. At lower temperatures, the growth is amorphous, while at higher temperatures, copper may not be incorporated into the film. Copper incorporation is also affected by oxygen flux. In all cases, the films are semiconducting or insulating as grown, and become superconducting only after high-temperature oxygen anneals. We comment on the prospects for obtaining true epitaxy superconducting phase in situ.

• Research Organization: Solid State Electronics Laboratory and Ginzton Applied Physics Laboratory, Stanford University, Stanford, California 94305
• OSTI ID: 5311324
• Journal Information: J. Vac. Sci. Technol., B; (United States), Journal Name: J. Vac. Sci. Technol., B; (United States) Vol. 6:2; ISSN JVTBD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360201 -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
656100 -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALKALINE EARTH METAL COMPOUNDS
ANNEALING
BARIUM COMPOUNDS
BARIUM OXIDES
CHALCOGENIDES
COATINGS
COHERENT SCATTERING
COPPER COMPOUNDS
COPPER OXIDES
CRITICAL CURRENT
CURRENT DENSITY
CURRENTS
DATA
DIFFRACTION
DYSPROSIUM COMPOUNDS
DYSPROSIUM OXIDES
ELECTRIC CURRENTS
ELECTRON DIFFRACTION
EPITAXY
EXPERIMENTAL DATA
FABRICATION
FILMS
HEAT TREATMENTS
HIGH TEMPERATURE
INFORMATION
LOW TEMPERATURE
MOLECULAR BEAM EPITAXY
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
RARE EARTH COMPOUNDS
SCATTERING
STRONTIUM COMPOUNDS
STRONTIUM OXIDES
SUPERCONDUCTING FILMS
THERMODYNAMIC PROPERTIES
TITANIUM COMPOUNDS
TITANIUM OXIDES
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE
ULTRALOW TEMPERATURE
VAPOR DEPOSITED COATINGS
VERY HIGH TEMPERATURE