Calculations of the thermal conductivity of Si1-xGex films with nonuniform composition

V. V. Kuryliuk; O. M. Krit

doi:10.15330/pcss.19.1.48-52

Authors

V. V. Kuryliuk Taras Shevchenko National University of Kyiv
O. M. Krit Taras Shevchenko National University of Kyiv

DOI:

https://doi.org/10.15330/pcss.19.1.48-52

Keywords:

thermal conductivity, film, silicon, germanium, Boltzmann equation

Abstract

SiGe films have attracted much attention recently due to experimental demonstrations of improved thermoelectric properties over those of the corresponding bulk material. However, despite this increasing attention, available information on the thermoelectric properties of Si_1-xGe_x films is quite limited, especially for nonuniform composition in wide temperature interval. In this paper we have used the Boltzmann equation under the relaxation-time approximation to calculate the thermal conductivity of Si_1-xGe_x films with nonuniform composition. It is confirmed that SiGe films with nonuniform composition has significantly lower thermal conductivity than its uniform counterpart. This suggests that an improvement in thermoelectric properties is possible by using the SiGe films with nonuniform distribution of germanium.

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