Preparation of CaMgSi and Ca7Mg7.25Si14 single phase films and their thermoelectric properties

Abstract

Ca-Mg-Si films were firstly prepared on (001)Al2O3 substrates by RF-magnetron sputtering method from Mg disc target together with Ca and Si chips. The composition of the deposited films was controlled by adjusting deposition temperature and Ca/Si area ratio of Ca and Si chips on Mg disk target. Ca0.32Mg0.33Si0.35 film deposited at 610 K consisted of a single phase of CaMgSi and this CaMgSi phase was stable after heat treated at 770 K under an atmospheric Ar with 5% -H2. As-deposited film shows the semiconductor behavior and have a power factor of 50 µW/(mK2) at 670 K, while annealed one showed the metallic behavior and its power factor down below 10 µW/(mK2) at 320-770 K. On the other hand, Ca0.27Mg0. 51Si0.2 film deposited at 590 K showed no obvious crystalline phase but became single phase of Ca7Mg7.25Si14 after heat treatment at 770 K under an atmospheric Ar with 5% -H2. As deposited film had a large power factor of 100 µW/(mK2) at 670 K. However, power factor decreased below 1 µW/(mK2) at 320-770K after the heat treatment at 770 K under an atmospheric Ar with 5% -H2.

This is a preview of subscription content, access via your institution.

References

  1. 1.

    T. Kato, Y. H. Sago, and H. Fujiwara, J. Appl. Phys. 110, 063723–1–5 (2011).

    Google Scholar 

  2. 2.

    N. G. Galkin, S. V. Vavanova, A. M. Maalsov, K. N. Galkin, A. V. Garasimenko, and T. A. Kaidalova, Thin Solid Films 515, 8230–8236 (2007).

    CAS  Article  Google Scholar 

  3. 3.

    A. Vantomme, G. Langouche, J. E. Mahan, and J. P. Becker, Microelectron Eng. 50, 237–242 (2000).

    CAS  Article  Google Scholar 

  4. 4.

    J. Tani and H. Kido, J. Ceram. Soc. Jpn. 123, 298–301 (2015).

    CAS  Article  Google Scholar 

  5. 5.

    T. Kajikawa, K. Shiba, K. Shiraishi, and T. Ito, 17th Inter. Conf. Proc. Thermoelectronics 17, 362–369 (1998).

    Google Scholar 

  6. 6.

    S. Ogawa, A. Katagiri, T. Shimizu, M. Matsushima, K. Akiyama, Y. Kimura, H. Uchida, and H. Funakubo, J. Electro. Mater. 43, 2269–2273 (2014).

    CAS  Article  Google Scholar 

  7. 7.

    K. Akiyama, A. Katagiri, S. Ogawa, M. Matsushima, and H. Funakubo, Phys. Status Solidi C 10 1688–1691 (2013).

    CAS  Article  Google Scholar 

  8. 8.

    A. Katagiri, S. Ogawa, M. Uehara, P.S. Sankara Rama Krishnan, M. Kurokawa, M. Matsushima, T. Shimizu, K. Akiyama, H. Funakubo, J. Mater. Sci. 53, 5151–5158, (2018).

    CAS  Article  Google Scholar 

  9. 9.

    M. Kurokawa, T. Shimizu, M. Uehara, A. Katagiri, K. Akiyama, M. Matsushima, H. Uchida, Y. Imura, and H. Funakubo, Mater. Res. Soc. Proc. 1642 (2014) DOI:https://doi.org/10.1557/adv.2018.150.

  10. 10.

    W.F. McDonough and S. Sun, Chem. Geol. 120, 223–253 (1995).

    CAS  Article  Google Scholar 

  11. 11.

    Y. Niwa, Y. Todaka, T. Masuda, T. Kawai, and M. Umemoto, Mater. Trans. 50, 1725–1729 (2009).

    CAS  Article  Google Scholar 

  12. 12.

    J. Grobner, I. Chumak, and R. Schmid-Fetzer, Intermetallics. 111, 1065–1074 (2003).

    Article  Google Scholar 

Download references

Author information

Affiliations

Authors

Corresponding author

Correspondence to Matsuo Uehara.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Uehara, M., Katagiri, A., Kurokawa, M. et al. Preparation of CaMgSi and Ca7Mg7.25Si14 single phase films and their thermoelectric properties. MRS Advances 4, 1503–1508 (2019). https://doi.org/10.1557/adv.2019.129

Download citation