Watling, J.R. and Paul, D.J. (2011) A study of the impact of dislocations on the thermoelectric properties of quantum wells in the Si/SiGe materials system. Journal of Applied Physics, 110, p. 114508. (doi: 10.1063/1.3665127)
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Publisher's URL: http://dx.doi.org/10.1063/1.3665127
Abstract
Thermoelectric materials generate electricity from thermal energy using the Seebeck effect to generate a voltage and an electronic current from a temperature difference across the semiconductor. High thermoelectric efficiency ZT requires a semiconductor with high electronic conductivity and low thermal conductivity. Here, we investigate the effect of scattering from threading dislocations of edge character on the thermoelectric performance of individual n and p-channel SiGe multiple quantum well structures. Our detailed physical simulations indicate that while the thermal and electrical conductivities decrease with increasing dislocation scattering/density, the Seebeck coefficient actually increases with increasing threading dislocation density above 10<sup>6</sup> cm<sup>-2</sup> at room temperature, due to an increase in the entropy associated with each carrier. The collective result of these individual effects, is that the present Si-based quantum well designs can tolerate scattering by a threading dislocation density up to ~10<sup>8</sup> cm<sup>-2</sup>, well within the capabilities of modern growth techniques, before significant reductions in ZT due to scattering from threading dislocations is observed.
Item Type: | Articles |
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Status: | Published |
Refereed: | Yes |
Glasgow Author(s) Enlighten ID: | Watling, Dr Jeremy and Paul, Professor Douglas |
Authors: | Watling, J.R., and Paul, D.J. |
College/School: | College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering |
Journal Name: | Journal of Applied Physics |
Publisher: | American Institute of Physics |
ISSN: | 0021-8979 |
Published Online: | 12 December 2011 |
Copyright Holders: | Copyright |
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