Increased Phonon Scattering by Nanograins and Point Defects in Nanostructured Silicon with a Low Concentration of Germanium
The mechanism for phonon scattering by nanostructures and by point defects in nanostructured silicon (Si) and the silicon germanium (Ge) alloy and their thermoelectric properties are investigated. We found that the thermal conductivity is reduced by a factor of 10 in nanostructured Si in comparison...
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| 语言: | en_US |
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American Physical Society
2010
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| 在线阅读: | http://hdl.handle.net/1721.1/51346 https://orcid.org/0000-0001-8492-2261 https://orcid.org/0000-0002-3968-8530 |
| _version_ | 1826201430771367936 |
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| author | Guilbert, H. Ren, Z. F. Lan, Y. C. Wang, D. Z. Lee, H. Yang, J. Joshi, G. Wang, X. W. Vashaee, D. Chen, Gang Dresselhaus, Mildred Pillitteri, A. Zhu, G. H. |
| author2 | Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science |
| author_facet | Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science Guilbert, H. Ren, Z. F. Lan, Y. C. Wang, D. Z. Lee, H. Yang, J. Joshi, G. Wang, X. W. Vashaee, D. Chen, Gang Dresselhaus, Mildred Pillitteri, A. Zhu, G. H. |
| author_sort | Guilbert, H. |
| collection | MIT |
| description | The mechanism for phonon scattering by nanostructures and by point defects in nanostructured silicon (Si) and the silicon germanium (Ge) alloy and their thermoelectric properties are investigated. We found that the thermal conductivity is reduced by a factor of 10 in nanostructured Si in comparison with bulk crystalline Si. However, nanosize interfaces are not as effective as point defects in scattering phonons with wavelengths shorter than 1 nm. We further found that a 5 at. % Ge replacing Si is very efficient in scattering phonons shorter than 1 nm, resulting in a further thermal conductivity reduction by a factor of 2, thereby leading to a thermoelectric figure of merit 0.95 for Si95Ge5, similar to that of large grained Si80Ge20 alloys. |
| first_indexed | 2024-09-23T11:51:47Z |
| format | Article |
| id | mit-1721.1/51346 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T11:51:47Z |
| publishDate | 2010 |
| publisher | American Physical Society |
| record_format | dspace |
| spelling | mit-1721.1/513462022-09-27T22:26:31Z Increased Phonon Scattering by Nanograins and Point Defects in Nanostructured Silicon with a Low Concentration of Germanium Guilbert, H. Ren, Z. F. Lan, Y. C. Wang, D. Z. Lee, H. Yang, J. Joshi, G. Wang, X. W. Vashaee, D. Chen, Gang Dresselhaus, Mildred Pillitteri, A. Zhu, G. H. Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology. Department of Mechanical Engineering Dresselhaus, Mildred Dresselhaus, Mildred Lee, H. Chen, Gang The mechanism for phonon scattering by nanostructures and by point defects in nanostructured silicon (Si) and the silicon germanium (Ge) alloy and their thermoelectric properties are investigated. We found that the thermal conductivity is reduced by a factor of 10 in nanostructured Si in comparison with bulk crystalline Si. However, nanosize interfaces are not as effective as point defects in scattering phonons with wavelengths shorter than 1 nm. We further found that a 5 at. % Ge replacing Si is very efficient in scattering phonons shorter than 1 nm, resulting in a further thermal conductivity reduction by a factor of 2, thereby leading to a thermoelectric figure of merit 0.95 for Si95Ge5, similar to that of large grained Si80Ge20 alloys. National Science Foundation Department of Energy 2010-02-03T14:24:48Z 2010-02-03T14:24:48Z 2009-05 2008-11 Article http://purl.org/eprint/type/JournalArticle 0031-9007 http://hdl.handle.net/1721.1/51346 Zhu, G. H. et al. “Increased Phonon Scattering by Nanograins and Point Defects in Nanostructured Silicon with a Low Concentration of Germanium.” Physical Review Letters 102.19 (2009): 196803. (C) 2010 The American Physical Society. https://orcid.org/0000-0001-8492-2261 https://orcid.org/0000-0002-3968-8530 en_US http://dx.doi.org/10.1103/PhysRevLett.102.196803 Physical Review Letters Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Physical Society APS |
| spellingShingle | Guilbert, H. Ren, Z. F. Lan, Y. C. Wang, D. Z. Lee, H. Yang, J. Joshi, G. Wang, X. W. Vashaee, D. Chen, Gang Dresselhaus, Mildred Pillitteri, A. Zhu, G. H. Increased Phonon Scattering by Nanograins and Point Defects in Nanostructured Silicon with a Low Concentration of Germanium |
| title | Increased Phonon Scattering by Nanograins and Point Defects in Nanostructured Silicon with a Low Concentration of Germanium |
| title_full | Increased Phonon Scattering by Nanograins and Point Defects in Nanostructured Silicon with a Low Concentration of Germanium |
| title_fullStr | Increased Phonon Scattering by Nanograins and Point Defects in Nanostructured Silicon with a Low Concentration of Germanium |
| title_full_unstemmed | Increased Phonon Scattering by Nanograins and Point Defects in Nanostructured Silicon with a Low Concentration of Germanium |
| title_short | Increased Phonon Scattering by Nanograins and Point Defects in Nanostructured Silicon with a Low Concentration of Germanium |
| title_sort | increased phonon scattering by nanograins and point defects in nanostructured silicon with a low concentration of germanium |
| url | http://hdl.handle.net/1721.1/51346 https://orcid.org/0000-0001-8492-2261 https://orcid.org/0000-0002-3968-8530 |
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