Hostname: page-component-7479d7b7d-767nl Total loading time: 0 Render date: 2024-07-10T07:50:40.135Z Has data issue: false hasContentIssue false
  • English
  • Français

Structural Studies of GeTe-AgSbTe2 Alloys

Published online by Cambridge University Press:  01 February 2011

Alan Thompson ,
Jeff Sharp ,
C.J Rawn  and
B.C. Chackoumakos
Alan Thompson
Affiliation:
athompson@marlow.com, Marlow Industries, Materials Research and Development, 10451 Vista Park Rd., Dallas, TX, 75238, United States, 214-342-4233
Jeff Sharp
Affiliation:
jsharp@marlow.com, Marlow Industries, Materials Research and Development, 10451 Vista Park Rd., Dallas, TX, 75238, United States
C.J Rawn
Affiliation:
rawncj@ornl.gov, Oak Ridge National Laboroatory, Materials Science and Technology, Oak Ridge, TX, 37831, United States
B.C. Chackoumakos
Affiliation:
chackoumakobc@ornl.gov, Oak Ridge National Laboroatory, Materials Science and Technology, Oak Ridge, TX, 37831, United States
Get access

Abstract

GeTe, a small bandgap semiconductor that has native p-type defects due to Ge vacancies, is an important constituent in the thermoelectric material known as “TAGS” [1]. TAGS is an acronym for alloys of GeTe with AgSbTe2, and compositions are normally designated as TAGS-x, where x is the fraction of GeTe. TAGS-85 is the most important with regard to applications, and there also is commercial interest in TAGS-80. The crystal structure of GeTe1+δ has a composition-dependent phase transformation at a temperature ranging from 430°C (δ = 0) to ∼ 400°C (δ = 0.02) [2]. The high temperature form is cubic. The low temperature form is rhombohedral for δ < 0.01, as is the case for good thermoelectric performance. Addition of AgSbTe2 shifts the phase transformation to lower temperatures, and one of the goals of this work is a systematic study of the dependence of transformation temperature on the parameter x. We present results on phase transformations and associated instabilities in TAGS compositions in the range of 70-85 at.% GeTe.

Keywords

thermoelectricityelectrical propertiessecond phases
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 1044: Symposium U – Thermoelectric Power Generation , 2007 , 1044-U03-09
Copyright
Copyright © Materials Research Society 2008

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

11. Skrabek, E. A. and Trimmer, D. S., “Properties of the General TAGS System,” in CRC Handbook of Thermoelectrics, ed. Rowe, D. M. (CRC Press, Boca Raton, FL, 1995), pp. 267–275.Google Scholar
2Ge-Te phase diagram, in Moffatt's Handbook of Binary Phase Diagrams, ed. Westbrook, J. H. (Genium Publ. Corp., Schenectady, NY, 1995).Google Scholar
3 Christakudis, G. Ch., Plachkova, S. K. and Shelimova, L. E., Physica Status Solidi A 111, 469–475 (1988)Google Scholar
4 Cook, B. A., Kramer, M. J., Wei, X., and Harringa, J. L., Journal of Applied Physics 101, 053715 (2007)Google Scholar
5 Spitzer, D.P., J. Phys. Chem. Solids 31, 19–40 (1970)Google Scholar
6 Baleva, M. I. and Plachkova, S. K., J. Physics C: Solid State Physics 16, 791–797 (1983)Google Scholar
7 Abrikosov, N. Kh., Dimitrova, S. K., Karpinskii, O. G., Plachkova, S. K. and Shelimova, L. E., Inorganic Material 20, No. 1, 42–46. (1984, English translation)Google Scholar
8 Christakudis, G. Ch., Plachkova, S. K. and Shelimova, L. E., and Avilov, E. Physica Status Solidi A, Vol. 128 4652 (1991)Google Scholar