Reduced Thermal Conductivity in Silicon Thin-Films via Vacancies


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An experimental method is defined that reduces the thermal conductivity in Si films by ~90 % compared to control samples, while keeping the thermoelectric power factor almost unchanged. This is done by creating vacancy-rich films via high-energy self-implantation of Si, followed by rapid-thermal annealing. TCAD simulations suggest that this approach is scalable for application in thin-film thermoelectric generators, as an alternative to more expensive and less Earth-abundant materials such as bismuth telluride. This approach to Si thermoelectrics could be straight-forward for scale-up to thin-film device dimensions, something that is a major challenge for other methods used for Si thermal conductivity reduction.



Solid State Phenomena (Volume 242)

Edited by:

P. Pichler




N. M. Wight and N. S. Bennett, "Reduced Thermal Conductivity in Silicon Thin-Films via Vacancies", Solid State Phenomena, Vol. 242, pp. 344-349, 2016

Online since:

October 2015




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