skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: YBa 2Cu 3O 7-δ Formation by Processing of Laser-Ablated, Fluorine-Free Precursor Films

Abstract

Epitaxial YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} was formed by processing of laser-ablated, fluorine-free precursor films. The depositions were conducted at room temperature in low oxygen pressure on LaAlO{sub 3}(LAO) single crystal substrates. Processing was done in the same deposition chamber by heating the precursor film to reaction temperatures of 750-850degC in a reducing gas ambient, and then raising the oxygen pressure to the conversion point. Typical processing times are a few minutes, corresponding to minimum YBCO growth rates of 1 nm/s. XRD analysis shows epitaxial growth and high crystallinity, although measured {Tc} values are somewhat suppressed at 88 K, with resulting critical current density, J{sub c} of about 1 MA/cm2 at 77 K, as determined by magnetic hysteresis. Properties indicate that the materials lack appropriate level of defects needed both for rapid oxygenation and flux pinning.

Authors:
 [1];  [1];  [1];  [1];  [1];  [1];  [1];  [1];  [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
OE USDOE - Office of Electric Transmission and Distribution
OSTI Identifier:
931695
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Conference
Resource Relation:
Conference: Applied Superconductor Conference, Seattle, WA, USA, 20060827, 20060901
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; YTTRIUM OXIDES; BARIUM OXIDES; COPPER OXIDES; ABLATION; LASER RADIATION; PRECURSOR; CURRENT DENSITY; CRITICAL CURRENT; SUBSTRATES; CRYSTAL GROWTH; TRANSITION TEMPERATURE

Citation Formats

Kim, Kyunghoon, Zhang, Yifei, Feenstra, Roeland, Christen, David K, Christen, Hans M, Cook, Sylvester W, List III, Frederick Alyious, Tao, Jing, Pennycook, Stephen J, and Zuev, Yuri L. YBa2Cu3O7-δ Formation by Processing of Laser-Ablated, Fluorine-Free Precursor Films. United States: N. p., 2007. Web.
Kim, Kyunghoon, Zhang, Yifei, Feenstra, Roeland, Christen, David K, Christen, Hans M, Cook, Sylvester W, List III, Frederick Alyious, Tao, Jing, Pennycook, Stephen J, & Zuev, Yuri L. YBa2Cu3O7-δ Formation by Processing of Laser-Ablated, Fluorine-Free Precursor Films. United States.
Kim, Kyunghoon, Zhang, Yifei, Feenstra, Roeland, Christen, David K, Christen, Hans M, Cook, Sylvester W, List III, Frederick Alyious, Tao, Jing, Pennycook, Stephen J, and Zuev, Yuri L. Mon . "YBa2Cu3O7-δ Formation by Processing of Laser-Ablated, Fluorine-Free Precursor Films". United States. doi:.
@article{osti_931695,
title = {YBa2Cu3O7-δ Formation by Processing of Laser-Ablated, Fluorine-Free Precursor Films},
author = {Kim, Kyunghoon and Zhang, Yifei and Feenstra, Roeland and Christen, David K and Christen, Hans M and Cook, Sylvester W and List III, Frederick Alyious and Tao, Jing and Pennycook, Stephen J and Zuev, Yuri L},
abstractNote = {Epitaxial YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} was formed by processing of laser-ablated, fluorine-free precursor films. The depositions were conducted at room temperature in low oxygen pressure on LaAlO{sub 3}(LAO) single crystal substrates. Processing was done in the same deposition chamber by heating the precursor film to reaction temperatures of 750-850degC in a reducing gas ambient, and then raising the oxygen pressure to the conversion point. Typical processing times are a few minutes, corresponding to minimum YBCO growth rates of 1 nm/s. XRD analysis shows epitaxial growth and high crystallinity, although measured {Tc} values are somewhat suppressed at 88 K, with resulting critical current density, J{sub c} of about 1 MA/cm2 at 77 K, as determined by magnetic hysteresis. Properties indicate that the materials lack appropriate level of defects needed both for rapid oxygenation and flux pinning.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

Conference:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this conference proceeding.

Save / Share:
  • Self-assembled nanodots of CeO{sub 2} on (1 0 0) LaAlO{sub 3} substrates, generated in situ by means of a pulsed laser deposition method prior to the deposition of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO) films, have been used to modify the superconducting properties of resulting YBCO films. Structural characterization has indicated that CeO{sub 2} layers grow via van der Merwe three-dimensional mode and the islands eventually acquire a pancake type of structure with lateral dimension several times larger than vertical dimension. The three-dimensional growth of CeO{sub 2} islands with (1 0 0) preferred orientation is believed to be associated with itsmore » surface energy anisotropy. The magnetization versus temperature and magnetization versus field measurements and analysis have suggested that CeO{sub 2} can affect the superconducting properties of YBCO films favorably or adversely depending on the density of CeO{sub 2} nanodots on the substrate surfaces prior to the deposition of YBCO films.« less
  • Epitaxial YBa[sub 2]Cu[sub 3]O[sub 7[minus][delta]] thin films (YBCO) and YBa[sub 2]Cu[sub 3]O[sub 7[minus][delta]]/PrBa[sub 2]Cu[sub 3]O[sub 7[minus][delta]] multilayers (Y/Pr) were irradiated with high-energy heavy ions (770) Mev [sup 108]Pb under various directions [phi] relative to the c-axis. The irradiation resulted in columnar defects tilted by [phi] from the c-axis. The angular dependence of their pinning activity was studied by measuring the anisotropy of the critical current density. The J[sub c](B, T, [theta]) behavior of the irradiated YBCO thin films showed an additional peak, which exceeds the intrinsic pinning peak, exactly at the irradiation direction. The Y/Pr multilayers, however, showed an isotropicmore » J[sub c]-enhancement by a factor of 5, without any additional structure in the J[sub c](B, T, [theta]) curve. 14 refs., 2 figs.« less
  • Experimental demonstration of reduction in the number and size of particulates formed in the laser ablation deposition of YBa{sub 2}Cu{sub 3}O{sub 7{minus}}{sub {delta}} thin films is obtained by the use of a second laser which further heats and fragments the blowoff material in the plume formed by the first laser. This results in a smoother film with higher critical current density as compared to that obtained without the second laser irradiation of the plume.
  • A high quality superconducting film on a substrate with a low dielectric constant is desired for passive microwave circuit applications. In addition, it is essential that the patterning process does not effect the superconducting properties of the thin films to achieve the highest circuit operating temperatures. YBa2Cu3O7 superconducting films were grown on lanthanum aluminate substrates using laser ablation with resulting maximum transition temperature (T sub c) of 90 K. The films were grown on a LaAlO3 which was at 775 C and in 170 mtorr of oxygen and slowly cooled to room temperature in 1 atm of oxygen. These filmsmore » were then processed using photolithography and a negative photoresist with an etch solution of bromine and ethanol. Results are presented on the effect of the processing on T{sub c} of the film and the microwave properties of the patterned films.« less
  • We have measured the millimeter-wave surface resistance of YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} superconducting films in a gold-plated copper host cavity at 58.6 GHz between 25 and 300 K. High quality laser-ablated films of 1.2 {mu}m thickness were deposited on SrTiO{sub 3} and LaGaO{sub 3} substrates. Their transition temperatures ({Tc}'s) were 90.0 and 88.9 K, with a surface resistance at 70 K of 82 and 116 m{Omega}, respectively. These values are better than the values for the gold-plated cavity at the same temperature and frequency.