Ge/SiGe Superlattices for Thermoelectric Devices Grown by Low-Energy Plasma-Enhanced Chemical Vapor Deposition
Ge/SiGe multiple quantum wells are presented as efficient material for room-temperature thermoelectric generators monolithically integrated onto silicon. We have deposited and characterized 10-μm-thick heterostructures engineered for lateral devices, in which both heat and current flow parallel to the multilayer. In this paper we investigate in detail the structural and interface quality by means of x-ray diffraction and transmission electron microscopy. Thermoelectric measurements, giving a figure of merit of 0.04 to 0.08, together with mobility spectra and defect analysis suggest possibilities of even higher efficiency. Nevertheless, the high power factor of 2 mW/K2m to 6 mW/K2m is promising for applications.
KeywordsSilicon germanium multiple quantum well thermoelectrics
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- 1.D.M. Rowe, ed., Thermoelectrics Handbook: Macro to Nano (Boca Raton, FL: CRC Press Taylor and Francis, 2006).Google Scholar
- 8.S. Cecchi, T. Etzelstorfer, E. Müller, A. Samarelli, L.F. Llin, D. Chrastina, G. Isella, J. Stangl, and D.J. Paul, J. Mater. Sci. doi:10.1007/s10853-012-6825-0. Accessed September 2012 (2012).
- 9.D.J. Paul, A. Samarelli, L. Ferre-Llin, J.R. Watling, Y. Zhang, J.M.R. Weaver, P.S. Dobson, S. Cecchi, J. Frigerio, F. Isa, D. Chrastina, G. Isella, T. Etzelstorfer, J. Stangl, and E. Müller Gubler, Proceedings of the 12th IEEE International Conference on Nanotechnology (IEEE-NANO) (Piscataway, NJ: IEEE, 2012), pp. 1–5.Google Scholar
- 10.A. Samarelli, L. Ferre Llin, Y. Zhang, J.M.R. Weaver, P. Dobson, S. Cecchi, D. Chrastina, G. Isella, T. Etzelstorfer, J. Stangl, E. Müller Gubler, and D.J. Paul, J. Electron. Mater. doi:10.1007/s11664-012-2287-z. Accessed November 2012 (2012).