The effect of shallow vs. deep level doping on the performance of thermoelectric materials
It is well known that the efficiency of a good thermoelectric material should be optimized with respect to doping concentration. However, much less attention has been paid to the optimization of the dopant's energy level. Thermoelectric materials doped with shallow levels may experience a drama...
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American Institute of Physics (AIP)
2018
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| Online Access: | http://hdl.handle.net/1721.1/118992 https://orcid.org/0000-0002-1090-4068 https://orcid.org/0000-0002-9872-5688 https://orcid.org/0000-0001-5799-5852 https://orcid.org/0000-0002-3968-8530 |
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| author | Broido, David Ren, Zhifeng Song, Qichen Zhou, Jiawei Meroueh, Laureen Chen, Gang |
| author2 | Massachusetts Institute of Technology. Department of Mechanical Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Mechanical Engineering Broido, David Ren, Zhifeng Song, Qichen Zhou, Jiawei Meroueh, Laureen Chen, Gang |
| author_sort | Broido, David |
| collection | MIT |
| description | It is well known that the efficiency of a good thermoelectric material should be optimized with respect to doping concentration. However, much less attention has been paid to the optimization of the dopant's energy level. Thermoelectric materials doped with shallow levels may experience a dramatic reduction in their figures of merit at high temperatures due to the excitation of minority carriers that reduces the Seebeck coefficient and increases bipolar heat conduction. Doping with deep level impurities can delay the excitation of minority carriers as it requires a higher temperature to ionize all dopants. We find through modeling that, depending on the material type and temperature range of operation, different impurity levels (shallow or deep) will be desired to optimize the efficiency of a thermoelectric material. For different materials, we further clarify where the most preferable position of the impurity level within the bandgap falls. Our research provides insight on why different dopants often affect thermoelectric transport properties differently and directions in searching for the most appropriate dopants for a thermoelectric material in order to maximize the device efficiency. |
| first_indexed | 2024-09-23T13:38:19Z |
| format | Article |
| id | mit-1721.1/118992 |
| institution | Massachusetts Institute of Technology |
| last_indexed | 2024-09-23T13:38:19Z |
| publishDate | 2018 |
| publisher | American Institute of Physics (AIP) |
| record_format | dspace |
| spelling | mit-1721.1/1189922022-09-28T15:13:53Z The effect of shallow vs. deep level doping on the performance of thermoelectric materials Broido, David Ren, Zhifeng Song, Qichen Zhou, Jiawei Meroueh, Laureen Chen, Gang Massachusetts Institute of Technology. Department of Mechanical Engineering Song, Qichen Zhou, Jiawei Meroueh, Laureen Chen, Gang It is well known that the efficiency of a good thermoelectric material should be optimized with respect to doping concentration. However, much less attention has been paid to the optimization of the dopant's energy level. Thermoelectric materials doped with shallow levels may experience a dramatic reduction in their figures of merit at high temperatures due to the excitation of minority carriers that reduces the Seebeck coefficient and increases bipolar heat conduction. Doping with deep level impurities can delay the excitation of minority carriers as it requires a higher temperature to ionize all dopants. We find through modeling that, depending on the material type and temperature range of operation, different impurity levels (shallow or deep) will be desired to optimize the efficiency of a thermoelectric material. For different materials, we further clarify where the most preferable position of the impurity level within the bandgap falls. Our research provides insight on why different dopants often affect thermoelectric transport properties differently and directions in searching for the most appropriate dopants for a thermoelectric material in order to maximize the device efficiency. 2018-11-13T17:21:39Z 2018-11-13T17:21:39Z 2016-12 2016-10 2018-11-07T16:00:25Z Article http://purl.org/eprint/type/JournalArticle 0003-6951 1077-3118 http://hdl.handle.net/1721.1/118992 Song, Qichen et al. “The Effect of Shallow Vs. Deep Level Doping on the Performance of Thermoelectric Materials.” Applied Physics Letters 109, 26 (December 2016): 263902 © 2016 Author(s) https://orcid.org/0000-0002-1090-4068 https://orcid.org/0000-0002-9872-5688 https://orcid.org/0000-0001-5799-5852 https://orcid.org/0000-0002-3968-8530 http://dx.doi.org/10.1063/1.4973292 Applied Physics 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 Institute of Physics (AIP) Other univ. web domain |
| spellingShingle | Broido, David Ren, Zhifeng Song, Qichen Zhou, Jiawei Meroueh, Laureen Chen, Gang The effect of shallow vs. deep level doping on the performance of thermoelectric materials |
| title | The effect of shallow vs. deep level doping on the performance of thermoelectric materials |
| title_full | The effect of shallow vs. deep level doping on the performance of thermoelectric materials |
| title_fullStr | The effect of shallow vs. deep level doping on the performance of thermoelectric materials |
| title_full_unstemmed | The effect of shallow vs. deep level doping on the performance of thermoelectric materials |
| title_short | The effect of shallow vs. deep level doping on the performance of thermoelectric materials |
| title_sort | effect of shallow vs deep level doping on the performance of thermoelectric materials |
| url | http://hdl.handle.net/1721.1/118992 https://orcid.org/0000-0002-1090-4068 https://orcid.org/0000-0002-9872-5688 https://orcid.org/0000-0001-5799-5852 https://orcid.org/0000-0002-3968-8530 |
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