Hostname: page-component-78c5997874-g7gxr Total loading time: 0 Render date: 2024-11-15T04:19:10.917Z Has data issue: false hasContentIssue false
  • English
  • Français

Origin of the (110) Orientation of Y2O3 and CeO2 Epitaxial Films Grown on (100) Silicon

Published online by Cambridge University Press:  15 February 2011

R. L. Goettler ,
J. P. Maria  and
D. G. Schlom
R. L. Goettler
Affiliation:
Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA, 16802–5005, schlom@ems.psu.edu
J. P. Maria
Affiliation:
Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA, 16802–5005, schlom@ems.psu.edu
D. G. Schlom
Affiliation:
Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA, 16802–5005, schlom@ems.psu.edu
Get access

Abstract

A perplexing issue in the growth of epitaxial oxide films on (100) silicon is the observed (110) orientation of yttria (Y2O3) and ceria (CeO2) despite the (100) orientation having a lower lattice mismatch. As expected, yttria-stabilized zirconia (YSZ) grows with the (100) orientation, yet it has a worse lattice match than both Y2O3(100) and CeO2(100) with silicon (100). The orientations observed would be expected if an epitaxial metal suicide layer forms initially during growth, before the oxidizing ambient is introduced. Calculation of the ensuing lattice mismatch between the oxide and suicide layer and multiplicity (σoxide) of the near coincident-site lattice for the oxide lattice shows that the (110) orientation is better lattice-matched than the (100) orientation for both Y2O3 (+2.3% × -2.4%, σoxide= 2, vs. -2.4% × +3.5%, σoxide = 4) and CeO2 (+1.8% × -4.0%, σoxide = 5, vs. 1.9% × 1.9%, σoxide= 5) and that for YSZ, (100) is better lattice matched than (110) (-0.8% × -1.6%, σoxide = 1, vs. -1.1 % × +4.8%, σoxide = 3). In each case, the in-plane orientation yielding the lowest mismatch with the suicide layer is consistent with the in-plane orientation observed between the oxide film and silicon substrate. Furthermore, the commonly observed rotational twinning in the oxide film can be accounted for by the expected orthogonal domain multipositioning in both the suicide and oxide layers. In CeO2, multipositioning allows two equally matched sets of orthogonal domains. One set consists of the two experimentally observed orientations (related by a 90° rotation). The other set is rotated 37° from the commonly observed orientations. Only the set with orientations aligned to the surface steps of Si(100) is observed, indicating the likely influence of graphoepitaxy in selecting between the two degenerate sets of orientations. When grown on Pt(100), Y2O3 grows with predominantly the (100) orientation and no (110) orientation, suggesting that without suicide formation, Y2O3 will grow with the expected well matched (100) orientation even when polar interfaces are involved.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 474: Symposium L – Epitaxial Oxide Thin Films III , 1997 , 333
Copyright
Copyright © Materials Research Society 1997

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

1 Harada, K., Nakanishi, H., Itozaki, H., and Yazu, S., Jpn. J. Appl. Phys. 30, 934 (1991).Google Scholar
2 Matthée, Th., Wecker, J., Behner, H., Friedl, G., Eibl, O., and Sawmer, K., Appl. Phys. Lett. 61, 1240 (1992).Google Scholar
3 Behner, H., Wecker, J., Matthée, Th., and Samwer, K., Surf. Interface Anal. 18, 685–90 (1992).Google Scholar
4 Yoshimoto, M., Nagata, H., Tsukahara, T., and Koinuma, H., Jpn. J. App. Phys. 29, L1199 (1990).Google Scholar
5 Inoue, T., Ohsuna, T., Yamada, Y., Wakamatsu, K., Itoh, Y., Nozawa, T., Sasaki, E., Yamamoto, Y., and Sakurai, Y., Jpn. J. App. Phys. 31, L1736 (1992).Google Scholar
6 Tarsa, E.J., McCormick, K.L., and Speck, J.S. in Epitaxial Oxide Thin Films and Heterostructures, edited by Fork, D.K., Phillips, J.M., Ramesh, R., and Wolf, R.M. (Mater. Res. Soc. Proc. 341, Pittsburgh, PA, 1994) pp. 73–85.Google Scholar
7 Binary Alloy Phase Diagrams, 2nd ed., edited by Massalski, T.B., Vol. 3 (ASM International, Materials Park, Ohio, 1990) pp. 1111, 3379, 3384.Google Scholar
8 Lee, Y.K., Fujimura, N., and Ito, T., J. Alloys Compd. 193, 289 (1993).Google Scholar
9 Aoki, H., Yata, M., Isoda, Y., and Uji, S., J. Magn. Magn. Mater. 104–107, 1905 (1992).Google Scholar
10 Tanaka, H., Konno, T.J., and Sinclair, R., J. Appl. Phys. 78, 4982 (1995).Google Scholar
10 δ = (a film - a substrate) / a substrate δ⊥ is the mismatch in the perpendicular direction.Google Scholar
12 Ravi, T.S., Hwang, D.M., Ramesh, R., Chan, S.W., Nazar, L., Chen, C.Y., Inam, A., and Venkatesan, T., Phys. Rev. B 42, 141 (1990).Google Scholar
13 Goettler, R.L., in preparation.Google Scholar
14 Landolt-Börnstein: Numerical Data and Functional Relationships in Science and Technology, New Seríes, edited by Madelung, O. (Springer-Verlag, Berlin, 1993), Group III, Vol. 24a, p. 352.Google Scholar
15 JCPDS (International Centre for Diffraction Data, Swathmore, PA), card 41–1105.Google Scholar
16 Bardal, A., Eibl, O., Matthée, Th., Friedl, G., and Wecker, J., J. Mater. Res. 8, 2112 (1993).Google Scholar
17 Inoue, T., Ohsuna, T., Obara, Y., Yamamoto, Y., Satoh, M., and Sakurai, Y., Jpn. J. App. Phys. 32, 1765 (1993).Google Scholar
18 Fenner, D.B., Viano, A.M., Fork, D.K., Connell, G.N., Boyce, J.B., Ponce, F.A., and Tramontana, J.C., J. Appl. Phys. 69, 2176(1991).Google Scholar