Abstract
We present electronic structure calculations of ordered Mg2Si as well as disordered Mg2Si1−x Sb x and Mg2−δ Si1−x Sb x systems, carried out by the Korringa–Kohn–Rostoker method with the coherent potential approximation (KKR-CPA). The computed densities of states (DOS) clearly show that a vacancy on the Mg site behaves as a double hole donor. Such electronic structure behavior together with n-type doping by antimony leads to electron–hole compensation. Consequently, the semiconductor–metal crossover expected in Mg2Si1−x Sb x due to the Fermi level shift into conduction states is not observed when important vacancy defects appear on the Mg site. Conversely, the Fermi level remains inside the energy gap if the antimony concentration is twice the vacancy concentration. The possible origin of vacancy formation in Mg2Si1−x Sb x is discussed based on the formation energy calculations as well as DOS features. Our KKR-CPA results well support recent electron transport properties measurements.
Similar content being viewed by others
References
Y. Noda, H. Kon, Y. Furukawa, N. Otsuka, I.A. Nishida, and K. Masumoto, Mater. Trans. JIM 33, 845 (1992).
J. Tani and H. Kido, Physica B 364, 218 (2005).
V.K. Zaitsev, M.I. Fedorov, I.S. Eremin, and E.A. Gurieva, Thermoelectrics Handbook, Chap. 29 (Boca Raton, FL: CRC Press, 2006).
K. Mars, G. Pont, L. Chaput, D. Fruchart, J. Tobola, and H. Scherrer, Proceedings of European Conference on Thermoelectrics (Paris, France, 2008).
K. Mars, H. Ihou-Mouko, G. Pont, J. Tobola, and H. Scherrer, J. Electron. Mater. 38, 1360 (2009).
G. Nolas, D. Wang, and M. Beekman, Phys. Rev. B 76, 235204 (2007).
A. Bansil, S. Kaprzyk, P.E. Mijnarends, and J. Tobola, Phys. Rev. B 60, 13396 (1999).
T. Stopa, S. Kaprzyk, and J. Tobola, J. Phys.: Condens. Matter 16, 4921 (2004).
S. Kaprzyk and A. Bansil, Phys. Rev. B 42, 7358 (1990).
P. Villars and K. Cenzual, Pearson’s Crystal Data: Crystal Structure Database for Inorganic Compounds (on CD-ROM), Version 1.0, Release 2007/8 (Materials Park, OH: ASM International).
J. Tani and H. Kido, Intermetallics 16, 418 (2008).
T.E.M. Staab, Phys. Status Solidi B 246, 1587 (2009).
V.K. Zaitsev, M.I. Fedorov, E.A. Guriewa, I.S. Eremin, P.P. Konstantinov, A.Y. Samunin, and M.V. Vedernikov, Phys. Rev. B 74, 0452071 (2006).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Tobola, J., Kaprzyk, S. & Scherrer, H. Mg-Vacancy-Induced Semiconducting Properties in Mg2Si1–x Sb x from Electronic Structure Calculations. J. Electron. Mater. 39, 2064–2069 (2010). https://doi.org/10.1007/s11664-009-1000-3
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11664-009-1000-3