Hostname: page-component-8448b6f56d-m8qmq Total loading time: 0 Render date: 2024-04-18T09:02:54.783Z Has data issue: false hasContentIssue false
  • English
  • Français

Transmission electron microscopic studies on growth mechanism of YBa2Cu3O7−y films formed by advanced trifluoroacetates metalorganic deposition process

Published online by Cambridge University Press:  31 January 2011

J. Matsuda ,
K. Nakaoka ,
T. Izumi ,
Y. Yamada  and
Y. Shiohara
J. Matsuda*
Affiliation:
Superconductivity Research Laboratory, International Superconductivity Technology Center (ISTEC), Koto-ku, Tokyo 135-0062, Japan
K. Nakaoka
Affiliation:
Superconductivity Research Laboratory, International Superconductivity Technology Center (ISTEC), Koto-ku, Tokyo 135-0062, Japan
T. Izumi
Affiliation:
Superconductivity Research Laboratory, International Superconductivity Technology Center (ISTEC), Koto-ku, Tokyo 135-0062, Japan
Y. Yamada
Affiliation:
Superconductivity Research Laboratory, International Superconductivity Technology Center (ISTEC), Koto-ku, Tokyo 135-0062, Japan
Y. Shiohara
Affiliation:
Superconductivity Research Laboratory, International Superconductivity Technology Center (ISTEC), Koto-ku, Tokyo 135-0062, Japan
*
a)Address all correspondence to this author. e-mail: junko.matsuda@aist.go.jp Present address: National Institute of Advanced Industrial Science and Technology (AIST), Energy Technology Research Institute, Tsukuba, Ibaraki 305-8565, Japan
Get access

Abstract

Microstructure evolution of YBa2Cu3O7−y (YBCO) films during the two heat-treatments in the advanced trifluoroacetates metalorganic deposition (TFA-MOD) process has been investigated by means of transmission electron microscopy. In the calcination process, precursor films including nanopores were formed through the shrinkage of the film after a remarkable increase of the thickness due to the thermal decomposition of metalorganic salts in the starting solution. During the crystallization process, the densification and shrinkage of the film occurred after agglomeration of nanopores and coarsening of unreacted phase particles such as Y2Cu2O5, CuO, and Ba–O–F in the precursor films. The YBCO films were then epitaxially grown with the remaining unreacted phase particles in the film, finally pores were generated again by a reaction of these unreacted particles to form YBCO accompanied by the volume reduction. It is important to control the densification of precursor films and coarsening of the unreacted phase particles in the crystallization process, to fabricate YBCO final films with fine crystallinity and high critical current values.

Keywords

Metalorganic depositionSuperconductingTransmission electron microscopy (TEM)
Type
Articles
Information
Journal of Materials Research , Volume 23 , Issue 12: Biomimetic and Bio-enabled Materials Science and Engineering , December 2008 , pp. 3353 - 3362
Copyright
Copyright © Materials Research Society 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1Tokunaga, Y., Honjo, T., Izumi, T., Shiohara, Y., Iijima, Y., Saitoh, T., Goto, T., Yoshinaka, A., Yajima, A.: Advanced TFA-MOD process of high critical current YBCO films for coated conductors. Cryogenics 44, 817 2004CrossRefGoogle Scholar
2Solovyov, V.F., Wiesmann, H.J., Wu, L-J., Suenaga, M., Feenstra, R.: High-rate deposition of 5 μm thick YBa2Cu3O7 films using the BaF2 ex-situ post annealing process. IEEE Trans. Appl. Supercond. 9, 1467 1999CrossRefGoogle Scholar
3Solovyov, V.F., Wiesmann, H.J., Wu, L-J., Zhu, Y., Suenaga, M.: Kinetics of YBa2Cu3O7 film growth by postdeposition processing. Appl. Phys. Lett. 76, 1911 2000CrossRefGoogle Scholar
4Solovyov, V.F., Wiesmann, H.J., Suenaga, M.: Growth rate limiting mechanisms of YBa2Cu3O7 films manufactured by ex situ processing. Physica C 353, 14 2001CrossRefGoogle Scholar
5Honjo, T., Nakamura, Y., Teranishi, R., Fuji, H., Shibata, J., Izumi, T., Shiohara, Y.: Growth mechanism of YBCO films in metal organic deposition method using trifluoroacetates. IEEE Trans. Appl. Supercond. 13, 2516 2003CrossRefGoogle Scholar
6Matsuda, J.S., Tokunaga, Y., Teranishi, R., Fuji, H., Kaneko, A., Asada, S., Honjo, T., Yajima, A., Iijima, Y., Saitoh, T., Izumi, T., Shiohara, Y.: Effects of heat-treatment conditions on microstructure of multi-coating Y123 films deposited by advanced TFA-MOD method. Physica C 412, 890 2004CrossRefGoogle Scholar
7Wesolowski, D.E., Yoshizumi, M., Cima, M.J.: Trajectory-property relationship in MOD-derived YBCO films. Physica C 450, 76 2006CrossRefGoogle Scholar
8Holesinger, T.G., Arendt, P.N., Feensta, R., Gapud, A.A., Specht, E.D., Feldmann, D.M., Larbalestier, D.C.: Liquid mediated growth and the bimodal microstructure of YBa2Cu3O7-δ films made by the ex situ conversion of physical vapor deposited BaF2 precursors. J. Mater. Res. 20, 1216 2005CrossRefGoogle Scholar
9Feldmann, D.M., Larbalestier, D.C., Holesinger, T., Feenstra, R., Gapud, A.A., Specht, E.D.: Evidence for extensive grain boundary meander and overgrowth of substrate grain boundaries in high critical current density ex situ YBa2Cu3O7-x coated conductors. J. Mater. Res. 20, 2012 2005CrossRefGoogle Scholar
10Civale, L., Maiorov, B., Serquis, A., Foltyn, S.R., Jia, Q.X., Arendt, P.N., Wang, H., Willis, J.O., Coulter, J.Y., Holesinger, T.G., MacManus-Driscoll, J.L., Rupich, M.W., Zhang, W., Li, X.: Influence of crystalline texture on vortex pinning near the ab-plane in YBa2Cu3O7 thin films and coated conductors. Physica C 412, 976 2004CrossRefGoogle Scholar
11Wong-Ng, W., Cook, L.P., Levin, I., Suh, J., Feenstra, R., Haugan, T., Barnes, P.: Phase equilibria of Ba–R–Cu–O for coated conductor applications (R = lanthanides and Y). Physica C 408–410, 20 2004CrossRefGoogle Scholar
12Matsuda, J., Nakaoka, K., Teranishi, R., Kitoh, Y., Aoki, Y., Fuji, H., Yamada, Y., Izumi, T., Shiohara, Y.: Microstructure and crystallization mechanism of YBa2Cu3O7−y films formed by advanced TFA-MOD process. Physica C 445, 563 2006CrossRefGoogle Scholar
13Matsuda, J., Nakaoka, K., Sutoh, Y., Nakanishi, T., Yoshizumi, M., Yamada, Y., Izumi, T., Shiohara, Y.: Microstructual analysis on growth and crystallization mechanism of YBCO films deposited by advanced TFA-MOD process. Physica C 463, 712 2007CrossRefGoogle Scholar
14Nakaoka, K., Matsuda, J., Kitoh, Y., Goto, T., Yamada, Y., Izumi, T., Shiohara, Y.: Influence of starting solution composition on superconducting properties of YBCO coated conductors by advanced TFA-MOD process. Physica C 463, 519 2007CrossRefGoogle Scholar