Hostname: page-component-586b7cd67f-g8jcs Total loading time: 0 Render date: 2024-11-26T20:16:01.344Z Has data issue: false hasContentIssue false

Substrate dependence of the crystallinity and mosaic texture of YBa2Cu3O7−δ ultrathin films deposited by laser ablation

Published online by Cambridge University Press:  31 January 2011

C.C. Chin
Affiliation:
Superconductivity Research Laboratory, ISTEC, 13-10 Shinonome 1-chome, Koto-ku, Tokyo 135, Japan
H. Takahashi
Affiliation:
Superconductivity Research Laboratory, ISTEC, 13-10 Shinonome 1-chome, Koto-ku, Tokyo 135, Japan
T. Morishita
Affiliation:
Superconductivity Research Laboratory, ISTEC, 13-10 Shinonome 1-chome, Koto-ku, Tokyo 135, Japan
T. Sugimoto
Affiliation:
Inorganic Materials Research Laboratory, Ube Industries, Ltd., 1978-5 Kogushi, Ube-City, Yamaguchi 755, Japan
Get access

Abstract

C-axis oriented ultrathin films with good crystallinity were deposited by laser ablation on both SrTiO3 and NdGaO3 substrates. The full width at the half maximum of the rocking curves of the (005) peak δω of our ultrathin films with thickness d ≤ 150 Å is less than 0.11°, and the χmin of the 150 Å films on SrTiO3 determined by RBS is equal to 8.5%. SrTiO3 and NdGaO3 have different degrees of lattice mismatches of 2% and 0.2%, respectively, with YBa2Cu3O7−δ at the deposition temperature of 700 °C. To study the impact on the growth of YBa2Cu3O7−δ thin films by the lattice mismatch, the thickness dependence of the crystallinity of the films on SrTiO3 and NdGaO3 substrates was compared. δω of the films deposited on SrTiO3 increases slightly from 0.085° to 0.11° as d increases from 50 Å to 150 Å, but δω increases rapidly from d ≍ 150 Å and saturates at 0.35°. In contrast, films on NdGaO3 showed a rather flat thickness dependence of δω which is below 0.1°. We interpreted the rapid increase in δω of the films on SrTiO3 in terms of strain relaxation. Lattice matching is one of the key factors to obtain good crystallinity. The grains of the films on SrTiO3 and MgO are not flat and smooth but have “mosaic texture.” In contrast, the films on NdGaO3 have no mosaic texture. The possible origins of the mosaic texture are also discussed.

Type
Articles
Copyright
Copyright © Materials Research Society 1993

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

1Xi, X.X.Doughty, C.Walkenhorst, A.Kwon, C.Li, Q. and Venkatesan, T.Phys. Rev. Lett. 68, 1240 (1992), and references therein.Google Scholar
2Myoren, H.Harada, K.Miyamoto, A.Miyamoto, N. and Osaka, Y.Jpn. J. Appl. Phys. 30, 38963899 (1991).CrossRefGoogle Scholar
3Michikami, O.Asahi, M. and Asano, H.Jpn. J. Appl. Phys. 29, L298 (1990).CrossRefGoogle Scholar
4Li, Q.Meyer, O.Xi, X. X.Geerk, J. and Linker, G.Appl. Phys. Lett. 55, 310 (1989).Google Scholar
5Xi, X. X.Geerk, J.Linker, G.Li, Q. and Meyer, O.Appl. Phys. Lett. 54, 2367 (1989).CrossRefGoogle Scholar
6Venkatesan, T.Wu, X. D.Dutta, B.Inam, A.Hedge, M. S.Hwang, D. M.Chang, C. C.Nazar, L. and Wilkens, B.Appl. Phys. Lett. 54, 581 (1989).CrossRefGoogle Scholar
7Zheng, X-Y.Lowndes, D.H.Zhu, S.Budai, J.D. and Warmack, R.J.Phys. Rev. B45, 7584 (1992), and references therein.Google Scholar
8Terashima, T.Bando, Y.lijima, K.Yamamoto, K.Hirata, K.Hayashi, K.Kamigaki, K. and Terauchi, H.Phys. Rev. Lett. 65, 2684 (1990).Google Scholar
9Miyazawa, S.Mukaida, J. and Sasaura, M. Extended Abstracts of International Workshop on Superconductivity, co-sponsored by ISTEC and MRS, HI, 1992), p. 57.Google Scholar
10Tazoh, Y.Kobayashi, J.Mukaida, J.Sasaura, M. and Miyazawa, S. Extended Abstracts Jpn. Soc. Appl. Phys., autumn meeting 1992, p. 732.Google Scholar
11Hawley, M. E.Raistrick, I.D.Houlton, R.J.Garzon, F.H. and Piza, M.Ultramicroscopy 4244, 705 (1992).Google Scholar
12Muenchausen, R.E.Hawley, M.Foltyn, S. R.Wu, X.D.Dye, R. C., Garzon, F. H.Skofronick, G. L. and Carim, A. H.Physica C199, 445 (1992).Google Scholar
13Norton, M.G.Lisa, A.Summerfelt, R. Scott, and Carter, B.C.Appl. Phys. Lett. 55, 2348 (1989).Google Scholar
14Norton, M. G. and Carter, C. B.Physica C172, 4756 (1990).CrossRefGoogle Scholar