Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-08T02:22:16.041Z Has data issue: false hasContentIssue false

Temperature Dependent Growth of LaAIO3 Films on YBa2Cu3O7 C-Axis Films for Multilayer Structures

Published online by Cambridge University Press:  15 February 2011

M.E. Hawley
Affiliation:
Materials Science and Technology Division, Center for Materials Science, MS K765
R.J. Houlton
Affiliation:
Materials Science and Technology Division, MST-11, MS D429, Los Alamos National Laboratory, Los Alamos, NM 87545
I. A. Raistrick
Affiliation:
Materials Science and Technology Division, MST-11, MS D429, Los Alamos National Laboratory, Los Alamos, NM 87545
F.H. Garzon
Affiliation:
Materials Science and Technology Division, MST-11, MS D429, Los Alamos National Laboratory, Los Alamos, NM 87545
Get access

Abstract

Fabrication of ultra smooth films, free of micro-shorts, is essential to the development of High Temperature Superconducting (HTS) thin film devices. One such example is a SNS junction consisting of two HTS layers separated by a uniformly smooth continuous barrier material. Other schemes under consideration require multilayer structures of up to 5 - 7 epitaxially grown layers of complex oxide material. Successful fabrication of such devices necessitates understanding the epitaxial growth of polycrystalline oxide films on polycrystalline film templates. Toward this end we have developed a set of deposition parameters that produce high quality epitaxial insulating layers suitable for HTS device applications. All films in this study were grown by off-axis RF magnetron sputter deposition. LaAlO3 films were deposited over MgO grown YBa2Cu3O7 (YBCO) c-axis thin films at temperatures ranging from 200 to 700C and on virgin substrates at 600C. Atomic Force Microscopy, eddy current measurements, and x-ray diffraction techniques were used to monitor the effect of growth conditions on the resulting film crystallinity, nanostructure, and electrical properties.

Ex-situ interrupted growth characterization of these materials has yielded new insight into the processes that control the growth mechanism and resulting microstructure. All films were polycrystalline. Below 600C, LaAlO3 films were not epitaxial while films grown at 650C showed some <200> orientation. The shape of the underlying YBCO film is most clearly evident for the film grown at 400C. Surface roughness depended on the appearance of crystals on the film surface. The superconducting properties of the underlying YBCO film required O2 annealing prior to deposition of the LaAlO3 layer.

Type
Research Article
Copyright
Copyright © Materials Research Society 1995

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

1. Reagor, D., Houlton, R., Springer, K., Hawley, M., Jia, Q.X., Mombourquette, C., Garzon, F., and Wu, X.D., Appl. Phys. Lett., 1994 (submitted).Google Scholar
2. Houlton, R.J., Reagor, D.W., Hawley, M.E., Springer, K.N., Jia, Q.X., Mombourquette, C.B., Garzon, F.H., and Wu, X.D., Proc. Appl. Supercond. Conf., IEEE Trans. Appl. Supercond., 1994 (submitted).Google Scholar
3. Jia, Q.X., Wu, X.D., Foltyn, S.R.. Reagor, D., Hawley, M., Springer, K.N., Tiwari, P., Mombourquette, C., Houlton, R.J., Campbell, I.H., and Peterson, D.E., Proc. Appl. Supercond. Conf., IEEE Trans. Appl. Supercond., 1994 (submitted)Google Scholar
4. Drehman, A.J. Lt., MacDonald, B.L., Andrews, R.J., and Tedrow, P.M., IEEE Trans. Magn. 27, 1646 (1991).Google Scholar
5. Lee, A.E., Burch, J.F., Simon, R.W., Luine, J.A., Hu, R., and Schwarzbek, S.M., IEEE Trans. Magn. 27, 1365 (1991).Google Scholar
6. Lee, A.E., Platt, C.E., Burch, J.F., Simon, R.W., Goral, J.P., and Al-Jassim, M.M., Appl. Phys. Lett. 57 (19), 2019 (1990).Google Scholar
7. Tidjani, M.E., Gronsky, R., Kingston, J.J., Wellstood, F.C., and Clarke, J., Appl. Phys. Lett. 58 (7), 765 (1991).Google Scholar
8. Sakuta, K., Iyori, M., Kobayashi, T., Matsui, M., and Nakajima, M., IEEE Trans. Magn. 27, 1361 (1991).Google Scholar
9. Tanaka, S., Nakanishi, H., Matusuura, T., Higaki, K., Itozaki, H., and Yazu, S., IEEE Trans. Magn. 27, 1607 (1991).Google Scholar
10. Gieres, G., Schmidt, H., Hradil, K., Hosler, W., Seebock, R., Physica C 185–189, 2115 (1991).Google Scholar
11. Brandle, C.D. and Fratello, V.J., J. Mater. Res. 5 (10), 2160 (1990).Google Scholar
12. Sandu, V., Jaklovszky, J., Miu, D., Dragulinescu, D., Grigoriu, C., and Bunescu, M.C., J. Mater. Sci. Lett. 13,1222 (1994).Google Scholar
13. Sader, E., Schmidt, J., Hradil, K., and Wersing, W., Supercond. Sci. Technol. 4, 371 (1991).Google Scholar
14. Sader, E., Superdond. Sci. Technol. 6, 547 (1993).Google Scholar
15. Raistrick, I. D., and Hawley, M. E., Physical Review C 66, 172 (1993); in Interface in High Temperature Superconductors. edited by S. Shinde and Rudman, D.A. (Springer-Verlag, NY, NY, 1993) Chapter 2.Google Scholar
16. Hawley, M., Raistrick, I.D., Beery, J.G. and Houlton, R.J., Science 251,1587 (1991).Google Scholar