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Nonstoichiometry of Epitaxial FeTiO3+δ Films

Published online by Cambridge University Press:  10 February 2011

Tatsuo Fujii ,
Makoto Sadai ,
Masakazu Kayano ,
Makoto Nakanishi  and
Jun Takada
Tatsuo Fujii
Affiliation:
Department of Applied Chemistry, Okayama University, Okayama 700–8530, Japan
Makoto Sadai
Affiliation:
Department of Applied Chemistry, Okayama University, Okayama 700–8530, Japan
Masakazu Kayano
Affiliation:
Department of Applied Chemistry, Okayama University, Okayama 700–8530, Japan
Makoto Nakanishi
Affiliation:
Department of Applied Chemistry, Okayama University, Okayama 700–8530, Japan
Jun Takada
Affiliation:
Department of Applied Chemistry, Okayama University, Okayama 700–8530, Japan
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Abstract

Epitaxial thin films of (001)-oriented FeTiO3+δ were prepared on α-Al2O3(001) single crystalline substrates by helicon plasma sputtering technique. The FeTiO3+δ films had large oxygen nonstoichiometry, which seriously depended on both substrate temperature and oxygen pressure during the sputtering deposition. The valence states of Fe ions in FeTiO3+δ changed monotonically from Fe2+ to Fe3+ with decreasing the substrate temperature from 900 to 400°C or with increasing the oxygen pressure from 0.9 to 1.8×10-6 Pa. The change of Fe valence states from Fe2+ to Fe3+ induced the magnetic phase transition only for the films prepared at 900°C. The films containing Fe2+ were paramagnetic while those with Fe3+ were antiferromagnetic at room temperature. The oxygen nonstoichiometry of the FeTiO3+δ films was probably produced by cation vacancies and disarrangement of Fe3+ and Ti4+ ions, which randomly occupied both interstitial and substitutional sites of the FeTiO3 related structure.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 746: Symposia Q/R – Magnetoelectronics-Novel Magnetic Phenomena in Nanostructures – Advanced Characterization of Artificially Structured Magnetic Materials , 2002 , Q6.10
Copyright
Copyright © Materials Research Society 2003

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References

REFERENCES

1. Ishikawa, Y., J. Phys. Soc. Jpn. 17, p. 1835 (1962).Google Scholar
2. Ishikawa, Y., J. Phys. Soc. Jpn. 13, p.37 (1958).Google Scholar
3. Fujii, T., Ayama, K., Nakanishi, M., and Takada, J., J. Magn. Soc. Jpn. 22, S1, p.206 (1998).Google Scholar
4. Fujii, T., Ayama, K., Nakanishi, M., Sohma, M., Kawaguchi, K., and Takada, J., Mat. Res. Soc. Symp. Proc. 623, p. 191 (2000).Google Scholar
5. Pandey, R. K., Sunkara, S., and Muthusami, J., AIP Conf. Proc. 361, p. 193 (1996)Google Scholar
6. Powder diffraction files, JCPDS 29–733.Google Scholar
7. Powder diffraction files, JCPDS 33–664.Google Scholar
8. Briggs, R.A. and Sacco, A. Jr, Meal. Trans. 24A, p. 1257 (1993).Google Scholar
9. Berry, F.J., Greaves, C., Helgason, Ö., McManus, J., Palmer, H.M., and Williams, R.T, J. Solid State Chem. 151, p. 157 (2000).Google Scholar